Brakes - UNBC Blogs
Contents
Acknowledgments
Introduction
Anatomy of a Road Bike
Anatomy of a Mountain Bike
8
9
10
12
CHAPTER 1
Home Bicycle Repair
Boxing a bike
15
24
CHAPTER 2
Frames
27
CHAPTER 3
Suspension
Basic Suspension Adjustment
39
46
CHAPTER 4
Wheels and Tyres
Wheel Removal and Remounting
Clincher Removal, Repair
and Remounting
UST Tubeless Tyre Removal,
Repair and Remounting
Tubular Removal, Repair
and Remounting
Rim Maintenance and Repair
Spoke Maintenance and Replacement
Truing Wheels
49
66
68
72
76
124
126
128
CHAPTER 7
Freewheels and Cassettes
Basic Cassette and
Freewheel Maintenance
Cassette Removal and
Cassette Cog Disassembly
Freewheel Removal and Replacement
Freewheel Cog Removal
and Replacement
1 31
138
140
142
143
Chains
Chain Maintenance and Repair
1 45
152
CHAPTER 9
80
82
84
87
92
94
98
Shift Levers
Braze-On Shifter Installation
Bar-End Shifter Installation
Brake-Lever Shift Lever Installation
Twist-Grip Mountain Bike Shifter
Removal, Installation and Service
Mountain Bike Thumb Shifter Removal
and Installation
Three-Speed-Type Shifter Removal
and Installation
1 55
161
1 64
1 66
1 68
1 70
1 71
CHAPTER 10
1 01
CHAPTER 6
Cranksets
114
116
122
CHAPTER 8
CHAPTER 5
Hubs
Adjusting Cone-and-Locknut
Type Hubs
Cone-and-Locknut Type
Hub Overhaul
Overhauling and Adjusting a
Campagnolo Hub Equipped
with an Oversize Axle
Lubricating Sealed Cartridge Bearings
Crankarm Adjustment
Bottom Bracket Overhaul
Removal and Installation of a
Shimano Octalink Crankset
Chainring Maintenance
Sealed-Bearing Cartridge-Style
Bottom Bracket Installation
Removal and Installation of
Two-Piece Cranksets
1 03
Front Derailleurs
Front Derailleur Basic Maintenance
Front Derailleur Installation
Front Derailleur Adjustment
1 73
1 77
179
182
CHAPTER 11
Rear Derailleurs
185
Rear Derailleur Removal
and Installation
Rear Derailleur Cleaning and
Lubrication
Rear Derailleur Adjustment
1 92
1 94
1 96
CHAPTER 12
Headsets
199
Threaded Headset Adjustment
Threaded Headset Overhaul
Threadless Headset Adjustment
and Overhaul
208
210
214
Direct-Pull Cantilever
(V-Brake) Adjustment
Brake Pad Maintenance
252
254
CHAPTER 14
Handlebars and Stems
257
Handlebar and Stem Adjustment
Removing and Installing
Road Stem and Bar for
Threadless Headset
Taping a Handlebar
Installing Mountain Bike Stem
and Grips
265
268
270
272
CHAPTER 15
CHAPTER 13
Saddles and Seatposts
275
281
Brakes
217
Saddle Installation and Adjustment
Brake Lever Adjustment and Removal
Brake Cable Installation
Mountain Bike Lever
and Cable Installation
Aero Lever and Cable Installation
Sidepull Installation
Basics of Disc Brake Maintenance
Mechanical (Cable-Actuated)
Disc Brake Installation and
Setup (Avid and similar)
Hydraulic Disc Brake Installation
and Setup (Hayes and similar)
Hydraulic Disc Brake Installation
and Setup (Shimano, Hope,
Magura and similar)
Cantilever Installation
and Adjustment
232
233
237
CHAPTER 16
Pedals
287
238
240
242
244
294
Mountain Bike Clipless
Pedal Maintenance
Shimano SPD Pedal Bearing Overhaul 296
298
Conventional Pedal
Repair and Maintenance
300
Look Pedal Bearing Overhaul
246
CHAPTER 17
Gears
303
Glossary
Resources
Index
310
315
316
248
250
Acknowledgments
This, the fifth edition of Bicycling Magazine's Illustrated Bicycle Maintenance, would never have been
possible without the help of dozens of people and organizations. This book has been a collaborative
effort between the author and many talented and knowledgeable mechanics and product designers, as well
as photographers, artists and editors.
There is hardly time or space to personally thank everyone who has been involved, but here appear a
handful of key people who've gone to great lengths to ensure that this is the most comprehensive and
up-to-date resource of bicycle maintenance available.
Heidi Rodale
Alan Daniels
Aaron Murray
Dan Lipow
David Jones
Drew Frantzen
Jim Langley
Kathy LeSage
Mark Bowman
Matt Reigner
Mitch Mandel
Nancy N. Bailey
Nic Cheetham
Rita Baker
Sarah S. Dunn
Thank you to all the companies that loaned their
time, knowledge and products:
Ace and Belmont Wheelworks, Somerville and Belmont, MA
Answer-Manitou
Avid
Bacchetta
Bianchi USA
The Bicycle Museum of America
Bike Sport, Tracce, Pennsylvania
Bontrager
Burley Design Cooperative
Campagnolo USA
Cane Creek Components
Cannondale
Chris King Components
Crank Brothers
Euro-Asia Imports
Finish Line
FSA
Giant Bicycles
Hayes Disc Brake
Hope Technology
Hutchinson
Independent Fabrication
Iron Horse
LeMond Bicycles
Magura
Marzocchi
Maverick American
Michelin
Park Tool
Pedro's
Phil Wood
Quality Bicycle Products
RaceFace
RockShox
Seven Cycles
Shimano
South Mountain Cycles, Emmaus, Pennsylvania
Specialized Bicycles
SRAM
Tarrytown Cycles, Tarrytown, NY
Trek Bicycle Corp.
Titec
Tri-Flow
Ultimate Support Systems
United Bicycle Institute
United Bicycle (Tool) Supply
And finally, I'd like to thank some of the people
who've been influential and supportive, both in the
making of this book and throughout my years as a
writer and professional bicycle mechanic.
John and Jill Downs
Marjorie Howsen
Danielle Ciraulo
John Allis
Butch Balzano
Michael Browne
Chipps Chippendale
Ralph Cronin
Matt Eames
Leif Erickson
Chris Fallon
Adrian Fletcher
Clint Paige
JuliRae Mitchell
Jack Mowatt
Ed Nasjleti
Rob Reed
Matt Roy
Merlyn Townley
Dave Weagle
Karl Wiedermann
Tripp Wyckoff
Introduction
Almost two decades ago, the first edition of this
book was published. Much has changed in those
years. But edition after edition, the goal of
Bicycling Magazine's Illustrated Bicycle Maintenance
has been to keep up with and anticipate the pace
of that change, and to be the definitive source of
bicycle maintenance and repair techniques for
cycling enthusiasts of every stripe.
The craft of bicycle mechanics, though well
developed and documented for over a century, is
still largely passed on from master to apprentice
through guidance and shared experience, in much
the same way as any other traditional craft is
taught. Through this text, you will benefit in the
same spirit from the knowledge and experience
of not just one, but several bicycle mechanics
who have helped to shape this guide over the
years. With, no doubt, hundreds of years' experience between them, you could not hope to find
yourself in better company.
Within the pages of this book, you will be
introduced to and get to know all the parts of
your bike.You will learn which components
perform what functions, and you will learn how
they all come together to make your bicycle
work.Tools and supplies will be explained,
lending you insight as to which ones you will
need and what, though perhaps less necessary,
can improve the speed, accuracy and ease of each
repair. Then, you will take all of this together and
discover how all those bits and pieces are kept in
top working order by cleaning, inspecting, lubricating and adjusting.
A great deal of new information has been
added to this, the fifth edition, but not at the
expense of the old. Changes in technology occur
every year, but perhaps there has never been a
period where those changes have come as
quickly and as frequently as they have in the last
decade. The advent and evolutions of suspension
and disc brakes are clearly the most obvious
advancements in the way bicycles function, but
more subtle improvements in frame construction,
bearing design and component manufacture
have made the past few years an exciting and
challenging time for bicycle mechanics.
Still, there are a good many tried-and-tested
designs that have withstood the test of time and
that remain as functional today as they did
decades ago and these are highlighted and
explained in the same detail as the most current
technology. So, in this guide, you will find topics
of maintenance and repair covered for bicycles
ranging from the trusty 1970s ten-speed through
to the latest in dual-suspension mountain bikes.
Even if you don't intend to perform your own
repairs, knowing your bike, its component parts and
how they work together can dramatically improve
your cycling experiences. By learning to recognize
when something is out of kilter before it leads to a
more serious – and expensive – problem, you will
save time, money and possibly prevent injuries, too.
This book may be all the reference you need.
Then, there are those of you who want to save
even more by performing basic maintenance tasks
at home.You will likely be pleasantly surprised at
just how easy many of these procedures can be.
You will quickly learn that most components of a
bicycle are much more simple than they appear;
and that, with every new technique you learn and
apply, your savings will grow greater and greater.
Of course, there are those who want to go
even deeper. If you want to begin performing all
of your own routine bicycle maintenance, and
to explore the possibilities of taking on more
major repairs, this is the ideal first volume of an
entire library of guides, manuals and catalogues
that you can build, covering every minute detail
of bicycle maintenance.
Remember: the key to success lies not in
knowing the answers to everything, but in
knowing where to find them...
Anatomy
of a
Road Bike
Anatomy
of a
Mountain Bike
■ SADDLE RAIL
GRIP
SHIFT LEVER ■
STEM
a BRAKE LEVER
HEAD TUBE
FORK CROWN
■ FORK STANCHION
FORK ARCH •---11GiltIL
■ DOWN TUBE
FRONT DERAILLEUR
a PEDAL
TYRE
CHAPTER 1
Home Bicycle
Repair
Whether you ride a bicycle for fun, fitness, transport or an
adrenalin fix — or maybe all of these — you need this book.
Even if you think you never want to perform your own
repairs, knowing your bike intimately is an invaluable tool for
any cyclist. Just by taking this book from the shelf, you've
shown yourself to be a cycling enthusiast: someone who has
more than a passing interest in bicycles and cycling.You ride
your bike (maybe several) far, frequently or both. Perhaps you
ride only in fair weather, or perhaps you're out even when the
Postal Service wants to stay in. In either case, all that time
spent in the saddle of any bike results in wear and tear, no
matter what the quality of the bike.
Luckily for us, bicycles are nearly as fun and easy to service
as they are to ride.The bicycle is one of the few things left in
our lives that just about anyone — with a small amount of
coaching — can understand and maintain at home.Your car, as
a comparison, is intentionally shrouded in mystery, with anything not integral to its daily use hidden behind plastic and
glossy paint. Lights on the dashboard hint that something is
amiss, but only your dealer can coax the car to reveal its ailment with special diagnostic equipment that reads the millions of bits of information that the car's computer tracks.The
bicycle, though, is open and obvious. A lightweight framework of tubes proudly presents all the bicycle's mechanisms
for inspection and adjustment. Shapes, materials and dimensional standards have changed slightly as technology has progressed over the bicycle's nearly 150-year history, but form
still follows function on the bicycle, and the same simple
mechanical principles make it go and stop.
If you're a numbers person, you'll be pleased to find that
geometry and dimensional tolerances can dictate how and
when your bike works and doesn't work. And if you're not a
numbers person, you're equally in luck. How's this possible?
Despite the fact that bicycle components are designed with
very specific dimensions that allow them to work seamlessly
together, it's important to remember that the human interface
is what makes a bicycle work. Without a person, a bicycle
cannot stand on its own two wheels; it can't steer; it can't shift.
It needs a rider to be a bicycle. And like your favourite pair of
jeans, when something 'feels' right, it's usually right.
`So what does it really take?' you ask. 'And have I got it?'
Every cyclist needs a pump, a patch kit, a folding tool or mini
tool kit, and just a little bit of know-how to keep a favourite
bike — or any bike, for that matter — rolling along smoothly.
That's it. Really.
Hand tools are easy. There are many high-quality options
available from several manufacturers, and the good folks at
your local bike shop can help you decide which suits you
and your bike best. The Bicycling Guide to Complete Bicycle
Maintenance and Repair can take care of the rest; giving you
the knowledge and the confidence to start you on your
way to knowing your bike better than you ever have before
— because knowing your bike will make every ride more
enjoyable. And isn't that what it's really all about?
You Are in the Saddle
Maintaining your own bicycle can be relaxing, rewarding and
financially liberating. As parts wear, they need to be replaced
— and you'll pay the same amount for these whether the bike
shop installs them or you do it yourself. A good mechanic
costs money, though, and a cheap mechanic may end up
costing you more in the long run. So it stands to reason that
the cost (in time) of performing your own labour may be
repaid both financially — and in pride.
There are other good reasons to become your own bike
mechanic, too. The more you work on your bike, the more
you learn about it and the better it runs.You soon discover
that a tweak here and a tweak there is often all it takes to keep
things running right. You learn that some problems are easy
to correct and that some are difficult, and then you learn a
few tricks to prevent the difficult ones.You see the value of
preventive maintenance in minimizing expensive repairs.
Think how much more enjoyable, too, your rides with
friends will be if you can quickly diagnose and correct a roadside or trailside problem on a riding partner's bike.You can be
a hero and preserve precious ride time that might otherwise
be spent hobbling home.
Of course, unless you've made the greatest commitment of
all — to open your own full-service bicycle repair shop — there
will be repairs that are simply out of your grasp for lack of
16
ILLUSTRATED BICYCLE MAINTENANCE
Took of the Trade
BICYCLE REPAIR
17
specialized tools. Things like frame-alignment tables and
facing tools are just too expensive and infrequently needed to
justify for any home workshop. When these kinds of situations
arise, knowing the root cause can help a qualified professional
assist you much more quickly and efficiently — the way a
physician is more able to treat your physical ailments when
you've stated your symptoms clearly. These procedures will
be discussed in this book so you can understand and
identify them.
Creating a Special Work Space
Your home workshop should be in a comfortable, open space
with sufficient ventilation. Garages and cellars are the most
popular locations for a home work space, but be certain that
the lighting is good and the surrounding area is kept relatively
clean. A floor clean enough to eat off isn't necessary, but you
don't know frustration until you've chased a 3-mm (Vs-inch)
ball bearing across a cluttered basement!
In a space of about 2 by 2 metres (7 by 7 feet), you can
create a pretty comfortable bicycle repair station. This allows
for a workbench about 120 to 180 cm (4 to 6 feet) long by
60 cm (2 feet) deep for resting tools, small parts and a supply
of lubricants and cleaners. Opposite the workbench, you will
want a workstand to hold your bike. An ideally placed workstand will hold your bike about 1 metre (36 to 40 inches)
from the workbench, giving you enough room to move while
still keeping both bike and bench within easy reach. On the
back of your workbench, a pegboard with hooks to hold your
most frequently used tools will keep things organized and
efficient. Paint the pegboard a light colour to make your tools
more visible, then outline the tools with a black marker on
the board to help remind you where things go and what isn't
put away. A short piece of 4 x 2 (2 x 4) with holes drilled
through makes a great storage solution for screwdrivers, loose
hex keys, pens, picks and other small tools. Lastly, a shelf under
your workbench is handy for housing a small toolbox with
less frequently used tools, a small trash bucket, a rag bin and
some small bins for hardware and spare parts.
Hardware stores sell kits for building workbenches just like
the one described, but the sturdiest are easily constructed
with just a few 4 x 2s (2 x 4s) and a sheet of 2-cm (3/4-inch)
plywood (Spend a little extra on exterior-grade plywood. It's
more resistant to liquids that can cause your workbench top
to warp and peel.) Build your workbench about 85 to 90 cm
(34 to 36 inches) tall (or a little higher or lower if you're over
180 cm [6 feet] or under 150 cm [5 feet] tall). If you have a
larger area to play with, go ahead and build your workbench
240 cm (8 feet) long, and revel in all that extra elbowroom.
It's easiest to work on your bike when it's suspended a
couple of feet off the floor. This can be achieved in a number
of ways. A system as simple as two cords hanging from a rafter
with hooks to hold your bike at the correct level or a rack
Servicing your bicycle is easiest when the bike is held off the ground
by a quality workstand.
made from scrap 4 x 2s (2 x 4s) to hold your bike up by the
frame (the same way a rack on the back of a car works) serves
just fine for the purposes of most simple maintenance tasks.
Just be sure that there is clearance for the crank and wheels to
spin freely. For frequent use or for more complex jobs,
though, nothing beats a proper bicycle repair stand. Readymade stands come in versions to suit anyone from the most
casual home tinkerer to the seasoned pro. They work by
clamping onto the seatpost or a frame tube (be careful and
read the manual — some of these clamps are powerful enough
to crush a frame if not applied properly) and allow you to
rotate the bike up or down to bring the area you are working
on closer to you.
All this talk of garages, basements and extra space may be
making the apartment dwellers among us feel left out in the
cold, but there's no need to despair. Folding workbenches and
repair stands can disappear into a closet quickly and easily,
along with a small tool bag. Pick up a small linoleum remnant
from a flooring store and you can even save your carpet (and
security deposit!). Lay it down when working on your bike;
when you're finished, wipe it down and roll it up to hide away
with your portable bike shop.
It is likely that you already have many of the basic hand tools
you will need to get started working on your own bike. If not,
things like adjustable spanners, pliers, screwdrivers and combination spanners can be most economically purchased from your
local hardware store. Of course, if you like to 'keep it in the
neighbourhood', bicycle-specific tool manufacturers like
Pedro's and Park make shop-quality versions of these, as well as
all the speciality tools you may eventually want or need.We have
provided lists of what makes a 'good' assortment of tools for the
casual home mechanic and what could be an 'ultimate' assortment for those who want to be entirely self-sufficient. You'll also
18
ILLUSTRATED BICYCLE MAINTENANCE
To maintain a fleet of bikes requires a fleet of tools. This assortment is more
than the average home mechanic would likely need, but it would make a
good start for an aspiring pro mechanic.
need cutting oil (if you plan to tap or chase threads), electrical
tape, grease, solvents, spray tube, thread adhesive and wax. If
you're not sure where you fall, start small and add tools to your
collection as the need arises.
Now that your workspace is organized, you may want to
create a list of periodic maintenance tasks to hang next to
your favourite cycling calendar.
Avoid Problems through Preventive
Maintenance
Everybody has heard the saying 'An ounce of prevention
is worth a pound of cure'. Well, when it comes to bikes, an
ounce of preventive maintenance is worth a pound of
expensive repair.
The first part of preventive maintenance is also the simplest — keeping your tyres properly inflated. You'll find the
recommended pressure written on the tyre's sidewall. At least
every other ride for road bikes or once a week for mountain
bikes, check the pressure with a floor pump that has a gauge.
Maintaining the proper tyre pressure makes the bike roll most
efficiently. More important, it ensures that when you hit a rut
or pothole or rock, your wheels will have the best chance of
escaping damage.
Next on your list of priorities should be keeping your bike
clean and lubricated. Freeing your bike of the grime and grit
it inevitably picks up on the road and trail by wiping it down
regularly will help your machine perform better mechanically
and prevent corrosion. It's also easier to inspect your frame for
signs of corrosion and cracks at the tube junctions when the
frame is clean. Discovering these types of issues early gives you
the best chance of mitigating the problem and saving the frame
(or your front teeth).
At least once a month (or after every muddy ride), wipe
down your frame with a damp cloth. While you're at it, polish
your frame with a car wax or an all-in-one bike cleaner (you
can even use furniture polish for a quick spray and spruce-up).
Polishing your frame may seem like an indulgence in vanity,
but the polish or wax will give your paint job a slick surface
that dirt and grit will less easily adhere to and makes each subsequent cleaning easier.
Clean the rims ofyour wheels frequently because the grime
that builds up on them is passed along to your brake pads and
can reduce the brakes' effectiveness. At least once a month
(more frequently if you do a lot of riding on dirty road surfaces), clean your rims and brake pads with alcohol.
Inspect the brake pad surfaces that strike the rims, and use
an awl or pick to dig out any small stones, metal and debris
embedded in the pads. These will quickly cut into the rims,
damaging them over time. Then, scuff off the glaze that may
develop on your brake pads with a piece of emery cloth,
sandpaper or a fine file.
The grit and grime that makes its way into your hubs,
headset and bottom bracket is a little more difficult to
remove. In this case, you must disassemble the parts, clean
them and repack them in fresh grease.There are also preventive measures that you can take. Wrapping pipe cleaners
around the openings into your hubs or pulling sections of old
inner tubes over the upper and lower stacks on your headset
are cheap, effective ways of making a mechanical seal. These
techniques are described further in the chapters devoted to
these bike parts.
Besides inflating tyres and cleaning and lubricating, the
other primary maintenance tasks on a bike are to make sure
that parts are properly fastened and adjusted.
Some loose or improperly adjusted parts are dangerous.
Others simply lead to unnecessary wear and deterioration
of components. Both types of problems can be avoided by
frequent checking to make sure all parts of your bike are
properly tightened and adjusted.
Choosing Cleaning Materials
What do you use to clean a bike? Water, for starters. Some
:yclists hose down their bikes after a dirty ride. This technique is fine when using the trickle from a garden hose or
;quirts from a spray bottle. When you do this, just bounce the
bike on its tyres a couple times to shake off some of the water,
:hen let it air-dry in a warm place. Treat it the same way after
riding in a drenching rain. In both cases, if you have a leather
HOME BICYCLE REPAIR
GOOD ASSORTMENT
Bicycle Tools
General Tools
Phillips screwdrivers (#1 and #2)
Flat screwdrivers
5.5, 6.35 and 8 mm ( 7;2 " , Y4"
and 'Al
Tape measure
(i n centimetres and inches)
Hacksaw frame and blades
(18 and 32 tpi)
Standard pliers
Sharp knife
Water pump pliers
(Channel Lock, etc.)
Awl
Cone wrenches
(13 through 19 mm for adjusting
wheel axle bearings)
Schrader valve core remover
(to fix slow leaks in car-type
valves)
Needle-nose pliers
Cold chisels
(for cutting or carving metal)
Cable cutter
(cuts brake and shift cables
without fraying)
Locking pliers
(small, medium – Vice Grip, etc.)
Punches (for driving out or
aligning things)
Third hand tool
(for brake cable adjustments)
Diagonal cutter
Outside calipers
Hex keys (2, 2.5, 3, 4, 5, 6, 8
and 10 mm)
Small magnet
(useful for extracting ball
bearings from components)
Chain rivet extractor
(for removing, installing and
repairing chains)
Torx keys (T-7, T-25 and T-40 for
disc brake maintenance and
some chainring bolts)
Rubber gloves
Safety glasses or goggles
Metric combination wrench set
(6 through 17 mm)
Floor pump with gauge
Adjustable spanners
200 and 300 mm (8 and 12 inch)
Tyre levers
8-ounce ballpein hammer
Plastic, rubber or leather mallet
Scissors
Repair stand
Pedal wrench
(l ong-handled wrench with strong
jaws for removing and installing
pedals)
Cassette lockring remover
or freewheel remover that fits
the cogset(s) on your wheel(s)
Chain whips
(for holding cassettes steady
during lockring removal or
to disassemble freewheels)
Spoke keys that fit your spoke
nipples
Crank bolt wrench or 14 mm
socket and ratchet handle
ULTIMATE ASSORTMENT
Bicycle Tools
General Tools
Stainless steel ruler
15 cm (6 inches)
Sturdy bench vice
Solvent tank (a safe place to
clean parts and store solvent)
Vernier caliper (a precise tool for
checking component dimensions)
Electric drill and drill bits
Bondhus hex keys (hex keys
with a ball-shaped end ideal
for working in tight spaces; 2
through 6 mm and 8 and 10 mm)
Inside caliper
Torque wrench
Taps (for repairing threads; 5 mm
x 0.8, 6 mm x 1.0, 7 mm x 1.0,
8 mm x 1.0 and 10 mm x 1.0)
Grinder with wire wheel
Tap handle
Air compressor with blower
attachment (simplifies tyre
inflation and grip installation)
Thread pitch gauge
(for measuring threads)
Tapered reamer
(for enlarging holes by hand)
Medium and coarse, round and
flat files (for machining metal
parts by hand)
Hex key bits (to fit torque
wrench; 4, 5, 6 and 8 mm)
Snap ring pliers
Lockwire pliers and lockwire
(for securing disc brake hardware and for wiring mountain
bike grips in place)
Dishing gauge (for centring the
ri m over the axle when building
or truing wheels)
Truing stand
Spoke tensiometer
(for measuring spoke tension)
Dropout alignment tools
(for repairing bent dropouts)
Headset installation tools
(for installing headset cups and
crown races)
Spoke ruler
Derailleur hanger alignment tool
(for repairing bent hangers)
Rear triangle alignment
indicator bar (for checking frame
alignment)
Hydraulic disc brake bleed kit(s)
Crankarm remover(s)
Chainring bolt spanner
Bottom bracket tool(s) to fit your
bottom bracket(s)
Headset spanners
(if you have a threaded headset)
Suspension pump
(if you have air-sprung shocks)
19
20
ILLUSTRATED BICYCLE MAINTENANCE
PEDRO'S MINI HEX WRENCH
PEDRO'S RX MULTI-TOOL
CRANK BROS. MULTI-17
ARK TOOL MTB-7 RESCUE TOOL
Mini-tools come in many configurations to suit different needs. Even the most
basic can mean the difference between riding home and walking home.
saddle, you don't want to get it too wet, so wrap it in a plastic
bag to protect it. Avoid using pressurized water streams, like
those at a car wash for example, though. Too much force can
push water past the seals in your hubs, headset and bottom
bracket and force the grease out, increasing the frequency
with which you will need to service these bearings.
Along with the water, use a sponge and washing up liquid.
Some parts get too greasy and grimy to be cleaned with soap
and water. Chainrings, chains, the insides of hubs, headsets and
bottom brackets need to be cleaned with a degreaser or solvent. Which one you use depends on how difficult the part is
to clean. In general, the most aggressive solvents are the most
volatile, which means their vapours will quickly permeate the
air around you and may pose a health hazard.
Petrol and lacquer thinner are examples of readily available
solvents of this type. Both are very effective cleaners but also
are highly volatile and highly flammable. Don't use them.
WD-40 is a well-known product that contains several different solvents mixed with a light oil. The most aggressive
solvent in the mix quickly evaporates into the air if you leave
it sitting in an open container. For cyclists, WD-40 is most
useful in its spray form for loosening gummed-up parts in
derailleurs and chains. Bicycle-specific degreasers are available
in varying strengths from Pedro's and Finish Line. The advantage to using a bicycle-specific cleaner or degreaser is that
most are formulated to not harm the plastic or composite components that make up many of today's
high performance parts. As a general rule, keep
citrus-based cleaners on chains, cogs and chainrings and away from shifters, and minimize their
contact with your bike's paint.'Green' cleaners like
Pedro's Bio Cleaner (formerly Bio Degreaser) are
milder and will not harm plastics or paint in any
concentration. Use these to clean greasy residue
anywhere on your bike.
Best of all, these cleaners are environmentally friendly and,
in most cases, biodegradable. Despite the relatively benign
nature of these biodegradable cleaning products, wear rubber
gloves whenever using cleaning agents. In fact, wearing gloves
like Park's Nitrile rubber gloves is a good way to protect your
hands and keep clean while performing any bicycle repair.
Alcohol is less harsh to your skin than most solvents and
works for lighter jobs, such as cleaning brake pads and the
braking surfaces of your wheel rims.
Besides soap, water and degreaser, all you need to get your
bike parts clean are a bucket, plenty of rags, a few sponges,
pads and brushes. Scouring pads made of synthetic materials
that are kind to shiny metal surfaces are useful aids in cleaning
rims and removing road tar from bike frames. Old toothbrushes can be put to good use cleaning freewheel cogs,
chainring teeth and chains. Larger brushes work well for getting between spokes, around brakes and into the tight spots
on the frame. Experiment to find what works best for you,
put together a kit and store it in a bucket.
Disc brakes are extremely sensitive to oil, so special care
must be taken when cleaning the brake disc or rotor. Even the
;mall amount of oil on the surface of your skin is enough to
hinder disc brakes' performance or even ruin the brake pads
permanently. Use a cleaner specifically intended for disc
brakes and a perfectly clean rag to spray and wipe off the
rotors. In the absence of these products, alcohol is an acceptable substitute for cleaning rotors. Disc brake pads generally
should not be cleaned, but in a case of oil contamination, it is
sometimes possible to revive the pads by soaking them in
alcohol and then gently scuffing them on a piece of sandpaper
Dr emery cloth laid flat on your workbench.
Lubricants
Along with thorough cleaning, properly lubricating the
moving parts of your bike is extremely important. There are
many lubricants on the market, and here are some general
guidelines.
Grease This book frequently calls for the use of mediumweight grease. This is the lubricant recommended for all
HOME BICYCLE REPAIR
bearing installations on a bike as well as for threaded parts on
freewheels, bottom brackets, headsets, pedals and wheel axles.
The same grease can be used to lubricate as well as rustprotect brake and gear cables.
The bike greases marketed by Finish Line, Park and
Pedro's, among other bike-product companies, are the type
we have in mind. These greases are generally sold in tubes. If
)(Du expect to use a lot of grease, you may want to purchase a
tub of white lithium grease at an auto parts store. This is similar to bike grease and works just as well. Just make sure you
buy white lithium grease and not automotive bearing grease,
which contains molybdenum disulfide to help it handle high
temperatures. This grease is too thick for use on a bike.
When servicing suspension forks, be sure to read the
manual provided with the fork. Some models must be lubed
with a certain grease type. Using a lithium-based grease, for
instance, may damage the bushings inside the fork.
Oil Oils are used to lubricate the pivot points of brakes and
derailleurs, the cassette bearings (inside the cluster of gears on
the rear wheel) and the chain links. The internally geared
hubs on three-speed bikes also need a periodic healthy dose
of oil, as do suspension forks. In fact, most suspension forks
use oil as a way to control travel.
Many companies offer quality oils. Pedro's, Finish Line,
ProGold (the only lubricant to ever win Bicycling Magazine's
Editor's Choice Award), DT Swiss and a host of others offer
a wide variety of oils for different applications. Avoid the
familiar three-in-one oil because it is vegetable-based and will
gum up your bike's moving parts. For suspension forks, get
the oil recommended by the manual.
As with grease, so with oil. The automotive industry provides an alternative to the oil sold in bike shops. Ordinary
30-weight motor oil is a workable substitute. Pour it into a
squirt can and apply a few drops where needed. Fight the
temptation, however, to be frugal and put used motor oil to
use on your bicycle. Used motor oil contains microscopic
metal filings and develops an acidic quality from the introduction of carbon and heat in the combustion chamber. Both
of these will compromise metal surfaces and increase wear.
There is much debate over the question of the best
lubricant for chains, the bike component that is particularly
subject to the ravages of dirt and water. This is partly because
riding conditions vary so much. Here we offer general
recommendations.Try various types to determine what is best
for you.
As a general rule, wet lubricants (oils) work year-round
but are messier and require more frequent cleaning of your
drivetrain than dry lubricants, which are best suited to warm,
dry conditions and don't tend to attract dirt and grime quite
as much.
What you use on your chain is somewhat less important
than how you use it. Contrary to what some may believe, it
is not necessary to have a heavy coating of lubricant on the
outside of the chain or on the teeth of your chainrings and
cogs. Rather, it's the inner surfaces of the chain where wear
takes place — the interfaces of the pins, plates and rollers.
The correct way to lubricate your chain begins with a
clean chain. Removing the chain and soaking it in a solvent
or degreaser is a great way to do this, but not necessary. Chain
cleaning devices that soak and scrub the chain while it is still
in place on your bike do a great job, save you a step and keep
the whole process neat and tidy. In the absence of a chaincleaning box, you can simply soak a rag in degreaser and grip
it loosely on the chain while pedalling your drivetrain backwards.You'll need to repeat this several times to achieve the
results of soaking or of a mechanical chain-cleaning box. If
there are thick clumps of dry, dirty lubricant between the
chain links, scrub these out with an old toothbrush. If time
allows, it's best to let the chain dry for several hours.
Once your chain is clean, drip lubricant over the chain
while pedalling the drivetrain backwards. After lightly coating
the entire chain, continue the pedalling motion for 20 to 30
seconds to allow the lubricant to work its way into the
deepest parts of the chain. Use a clean rag to wipe the excess
lubricant from the outside of the chain. This last step leaves a
thin film of lubricant on the outside of the chain to inhibit
corrosion but minimizes the amount of grit that will stick to
the chain.Your chainring and cog teeth will receive enough
lubricant just from contact with the chain to fight corrosion.
BICYCLE TOOL KIT
Here are tools to carry when you ride
Spare tube (even if you use
tubeless tyres)
Tyre boots (special patches to
repair cuts in the tyre)
Identification (written inside your
helmet, too)
Tube patch kit (contains patches,
glue and sandpaper; check the
glue frequently since it tends to
dry out once opened)
Small length of wire (handy for
making temporary, 'get-home'
repairs on the road- or trail-side)
21
All-in-one mini tool such as the
Crank Brothers Multi 17 (a small
tool that includes 2, 2.5, 3, 4,
5, 6 and 8 mm hex keys; chain
tool; flat screwdriver; Phillips
screwdriver; T-25 Torx key;
spoke keys; and 8 and 10 mm
open spanners)
Frame pump or mini pump
(set to fit your type of valve)
Emergency money
Tyre levers
22
ILLUSTRATED BICYCLE MAINTENANCE
MAINTENANCE SCHEDULE
Before Every Ride
Dry off the saddle if it's wet.
Check tyre pressure.
If the chain got wet, wipe it
down and apply some fresh
chain lube.
Make sure that the chain is
properly lubricated.
Make sure that brakes grab firmly.
Make sure the wheels are centred in the frame and that the
quick releases are firmly closed.
Check that brakes are properly
aligned and that the pads are in
good condition.
Check and adjust pressure of airsprung suspension components.
Check hydraulic brake lines for
kinks or splits.
Bounce the bike to detect rattles
that might indicate loose or misadjusted parts.
Make sure bags and panniers
are secure and that no loose
straps can get caught in the
wheels.
Check that your pump and
repair kit are present.
After Every Ride
Brush foreign objects off the
tread and check the overall
condition of the tyres.
Wipe down or hose down the
bike if it's very dirty; be careful
not to direct water at bearings
or other sensitive components;
bounce the bike to shake off
excess water and store it in a
warm, dry place.
After a wet ride, remove the
seatpost, turn the bike upside
down and let the seat tube
drain; apply fresh grease or antiseize before reinstalling the post
(except where carbon fibre is
involved).
Check hydraulic brake lines for
kinks or splits.
Every Month
(or more often if riding five or
more days per week)
Wipe down the entire bike with
a wet rag.
Check for cracks or signs of
stress on the frame, rims, crank,
fork, handlebar and stem.
Hold the front wheel between
your knees and try to turn the
handlebar with one hand; if it
moves easily, tighten the stem
bolt(s).
give the chain, cogs and chainrings a quick degreasing on the
bike and relubricate the chain.
Lubricate the bushings of the
idler and jockey pulleys on the
rear derailleur.
Clean the legs of suspension forks
and the body of the rear shock;
then apply lubricant to the dust
wipers to keep them from drying
out.
Lubricate springs and pivot
points on clipless pedals.
Check that all brake hardware
is secure.
Check the spoke tension and
truness of wheels and adjust as
needed.
Every Six Months
Check the bearing adjustment on
front and rear hubs.
Check the adjustment on pedal
bearings.
Check the bottom bracket for
proper adjustment.
Check the seat tube for rust on
steel frames.
Check cables for kinks and
fraying.
Clean cables and flush cable housings with a light aerosol solvent.
Measure the chain and check the
cogs and chainrings for excessive wear; replace if necessary.
Check all hardware on the bike.
Check the condition of the brake
pads; replace if excessively or
unevenly worn; for rubber rimbrake pads, pick out debris with
an awl and remove glazing by
scuffing with a half-round file.
Clean rims with isopropyl
alcohol.
Check accessory hardware (racks,
bottle cages, etc.) for tightness.
Overhaul suspension forks, rear
shocks and rear suspension
pivots.
Every Year
Overhaul hubs.
Overhaul headset.
Replace cables and housings.
Replace worn parts such as
tyres, and brake pads.
Replace grips or handlebar wrap.
Check the condition of glue on
tubular (sew-up) tyres.
Add two to four drops of oil to
three-speed hubs.
Lubricate the pivot points on the
front and rear derailleurs.
Clean and treat leather saddles
with saddle soap or leather
dressing.
Check crankbolts and chainring
bolts for tightness.
Check headset for proper
adjustment.
Use these same steps before installing a new chain, as well.
New chains are coated with a protective, oil-based wax to
prevent rust while in shipping and storage, but it is not an
ideal lubricant. This protestant is very sticky and will attract
dirt and debris.
Keeping cables freely flowing through their housings follows two schools of thought. The first says that grease on the
cables will prevent water and grit from entering the housing.
However, some dirt will always be dragged into the housing
by the motion of the cable, so greased cables should be
removed, cleaned and regreased regularly. The other says that
a perfectly clean cable and housing allows the cable to move
quickly and smoothly, especially in modern, Teflon-lined
cable housings. Care, too, should be taken to ensure that the
Check rear suspension pivot
bolts for proper torque.
cables and housings remain clean by removing the cables
periodically and spraying a solvent or very light oil like
WD-40 through the housings to flush them.
Don't Be a Statistic
There's nothing like a trip to the hospital to put a dent in the
Sunday that you were devoting to tuning up your road
rocket. Worse, it's a terrible irony when you can't ride because
you hurt yourself fixing your machine. Fortunately for you,
aver the years we've made every dumb mistake a mechanic
can possibly make and are here to tell you about them. Keep
these in mind as you work and you'll escape the embarrassment and downtime of an injury. Also, take your time, use
:ommon sense, and be careful.
HOME BICYCLE REPAIR
Bad jab. When you're pushing down with a screwdriver,
knife, awl, electric drill — anything sharp — make sure your
free hand and any other body part aren't directly behind the
object you're operating on. If you slip, you'll likely cut, poke
or drill yourself.
Face job. Likewise, whenever you're pulling on things, keep
your face out of the way. The classic mistake is pulling up hard
to remove something, say a frozen seatpost or seat. When it
releases, you bash yourself in the face. Ouch.
Slice of life. Watch out for sharp parts. When removing
pedals, for instance, you're working around the chainrings
with all those nasty teeth (not just sharp, but greasy, too). A
good way to protect yourself is to always shift the chain onto
the large chainring before trying to remove or install a pedal.
That way, the teeth are covered. And watch out for frayed
cables, which can stick you like splinters.
Can clumsiness. When using spray lubes or cleaners, be sure
the nozzle is pointing away from your face. And don't drop
the cans because that can knock the nozzles off, leading to
broken cans that won't stop spraying. Also, read the labels
before use so you know what to do if you get the stuff in your
eyes. Be sure to work with spray lubes in ventilated areas only.
Splish-splash guard. When working with solvents, wear
rubber gloves to protect your skin and goggles to protect your
eyes from splashback.
Test-ride. After finishing a repair, test-ride the bike — but take
it easy. Even the best mechanics forget things. It's better to
pedal gently and test things at slow speeds than to vault into
the saddle and sprint down the road.
Basic Principles of Bicycle Maintenance
and Repair
Here are the guidelines that we live by when it comes to
bicycle maintenance and repair.
Think safety first. Wear rubber gloves to protect your hands
from solvents and grease. Don goggles to protect your eyes
when using hammers or power tools.
Don't wait until severe problems arise. Preventive maintenance is the best way to take care of your bike.
When lubricating your bike, use plenty of oil or grease,
then wipe away any excess that will attract grit. Don't wipe
off dirty grease that appears on the outside of bearings until
overhaul time; doing so will only get grit inside the bearings.
Most parts are turned to the right to tighten and to the left
to loosen. One way to remember this is to repeat, aighty,
tighty; lefty, loosey.' The common exceptions to this rule are
the left pedal and the right side of the bottom bracket.
23
Before installing any threaded part, check the threads to
see that they match. Don't mismatch threaded parts. And
never force things: always grease threads first, then start
threading them together carefully and gently.
Take it easy when tightening things. Bicycle components
are often made of lightweight materials and too much force
can strip threads and break parts.
Some repair jobs are better left to the experts. Learn to
make wise choices as to what you can handle and what's
better left to a trained mechanic.
RECOMMENDED LUBRICANTS
Part
Lubricant
Ball bearings
Medium weight bike grease
Bottom bracket spindle
Medium weight bike grease
(do not lubricate square-taper
spindles unless directed to by
the crankarm manufacturer)
Brake cable
Flush housing with aerosol
solvent; if desired, lubricate
using a lightweight oil
Brake pivot
Medium weight bike grease or
Teflon-based oil
Brake spring
Medium weight bike grease
Chain
Pick a chain lubricant; there
are lots out there for different
conditions
Derailleur pivots
Teflon-based oil
Internal gear hubs
Lightweight machine oil with
no particulate additives
Seatposts (steel or aluminium
Medium weight bike grease
Seatposts (titanium frame with
Antiseize compound
Seatposts (carbon fibre frame
Nothing (any type of lubricant
could cause slipping and
possibly compromise the
carbon fibre)
Stem (quill-type)
Medium weight bike grease;
substitute antiseize compound
if any titanium component is
involved
frame and/or seatpost)
steel, aluminium or titanium
seatpost; titanium seatpost with
steel, aluminium or titanium
frame)
with any material seatpost;
carbon fibre seatpost with any
material frame)
Stem (threadless type)
Nothing
Suspension fork dust wipers
Teflon-based oil
Threads
White lithium grease, medium
weight bike grease, antiseize
or thread-locking compound,
depending on the application
ILLUSTRATED BICYCLE MAINTENANCE
Boxing a Bike
1
To prevent cuts, remove any protruding staples from the box lids. Start
bike preparation by removing the pedals with a pedal wrench. Turn
the left pedal clockwise to loosen; turn the right pedal anticlockwise.
Place the pedals in a small-parts box. Shift onto the largest rear cog
and smallest chainring. To prevent damage, cover all the tubes and the left
crankarm with pipe insulation (see photo), bubble wrap or many sheets of
newspaper wrapped and taped. Loosen and remove the seat and seatpost as
a unit. If necessary, remove the handlebar and computer, carefully unwinding
the cable from the brake wire. Wrap the seat and seatpost, aero bar and computer. Place the computer in the small-parts box.
If you are taking your bike on a plane, deflate the tyres to about 25
psi so they won't burst. Air-sprung suspension should also be aired
down to prevent blown seals and oil weeping. Open both sidepull
brake quick-releases, unhook cantilever link wires, or release the noodle on
direct-pull cantilevers. If you have slotted cable stops, lift the brake housings
out of them. For the shift cables, click the right lever as if you're shifting to the
smallest cog, then pull on the front derailleur to create slack and release the
derailleur housing sections. Some bikes have stems that open so the handlebars can be removed with the levers and grips attached. If you have this type,
open the stem, remove the bar and reattach the stem parts (see photo).
For a non-opening stem, loosen and remove the top cap bolt on
hreadless forks and loosen the stem bolts. On threaded forks loosen
3 tthe stem bolt on top of the stem and tap it with a mallet to loosen the
stem. Remove the front sidepull brake by unscrewing the 5 mm hex key bolt
(don't disconnect the cable). For cantilevers, remove the side connected to the
cable. Reattach the sidepull nut and any washers and tape the cantilever parts
together. Wrap the brake so it can't scratch the frame. Lift off the stem and
handlebar. For threadless forks, place a cardboard tube that's about the same
width as your stem over the fork and reinstall the top cap and nut (see photo).
HOME BICYCLE REPAIR
4
25
Remove the front wheel. Unscrew and extract the front quickrelease, reassemble it and place it in the small-parts box. Install a
fork spacer or wood block between the dropouts (see photo) with
screws or tape. This prevents the fork from getting bent and from poking
through the box. Put the bike on the ground, level the crankarms and wrap
an elastic band around the seatstays and valve stem, which will keep the
rear wheel from rotating and changing the crankarm position.
. „___.. . .,
5
Place the front wheel on the left side of the bike, fitting it snugly by
working the left crankarm inside the spokes. When the wheel is in the
correct position, the axle will be between the seat and down tube and
won't be able to contact them. Just be certain that the hub is situated so it
cannot damage the frame. Then tie the wheel to the frame at the seat, down
and top tubes.
Place the handlebar/stem assembly alongside the top tube to find the narrowest way to attach it. Loosen the stem if necessary to rotate the bar inside
the stem. For drop handlebars, try placing the bar's hooks over the top tube
with the levers pointing upward and the stem inside the wheel (see photo).
6
IMF
.11111111■
Experiment to find the safest position for the brake levers, and wrap
them if they seem vulnerable. Rotate the fork 180 degrees.
Check the small-parts box to ensure that all pieces are inside, tape it shut
and place it in one end of the bike box. Lift and lower the bike into the
box, keeping the small-parts box between the fork and downtube. Make
sure that the crankarms are horizontal. Put the front brake wherever it fits.
Wrap the seat, aero bar/seatpost assembly and tie it next to the rear
wheel. If the front hub rubs the side of the box, tape a piece of cardboard
over the axle as a buffer.
CHAPTER 2
Frames
When asked, 'What kind of bike do you ride?' most of us will
quickly utter the name that appears on the bike's frame.
Indeed, though every bike is made up of a collection of parts
from several manufacturers, the frame builder gets credit for
making the bike what it is.This is not entirely incorrect, as the
details of each frame's construction determine how the bike
will behave more than any other single component.
Frames require little maintenance, and a damaged frame
,-an be properly repaired only by a qualified frame builder or
experienced professional mechanic. Still, your bicycle's frame
should not be taken for granted, so the focus of this chapter
will be to familiarize you with the aspects of frame construction, geometry and inspection for signs of trouble.
The frame is the most important part of your bicycle for
many reasons. The first aspect is geometry. Geometry is a
blanket term that refers to all the angles and dimensions that
make the bike fit and handle the way it does. It positions your
body for efficient pedalling by determining the locations of
the saddle, crankset and handlebars. The same geometry also
determines the handling, or behaviour, of a bike. How stable it
is when racing down trails, its willingness to cut corners and its
ability to carry loads are all determined by the specific relationships between each dimension of the frame's geometry.
It's si mply not possible to build a frame that optimizes all
of these factors, so trade-offs are made among them to make
your hike a racer, sports tourer, loaded tourer or mountain
bike. Beyond your frame's geometry, its construction material,
combined with the type of tyres, determines how comfortably or sportily it will ride.
You can change your bike's personality to some extent by
changing the parts that are hung on it. Lighter wheels, for
example, will liven up your bike's ride and make it climb and
accelerate more easily.Your bike's frame, though, determines
its general handling and comfort. Therefore, it's valuable to
learn to identify the principal parts of a typical frame and to
recognize different types of frames.
Frame Nomenclature
A bicycle's frame is often described by its halves: the front and
the rear triangles. The front triangle, which is also known as
the main triangle, is actually a quadrilateral. It consists of the
following tubes:
Head tube. This is located at the front of the frame and holds
the headset, or steering bearings.
Top tube. This connects the head tube and the seat tube,
which is under the saddle.
Seat tube. This runs from the seat down to the bottom
bracket and the bottom of the down tube.
Down tube.This runs from the head tube down to the bottom
bracket. The bottom bracket holds the bearings and axle of
the crankset.
The rear triangle consists of the chainstays and the seatstays. The chainstays are the twin tubes that connect the
bottom bracket and two rear axle holders known as the
dropouts. The seatstays are the twin tubes that connect the
dropouts and the junction of tubes under the saddle called the
seat cluster. Technically, the seat tube completes the triangle.
Completing the frame are the fork and the steerer tube.
The fork consists of two fork blades that are attached to a
horizontal piece known as the fork crown. On suspension
forks, the blades are most often referred to as 'legs', each of
which is made up of two primary parts. The smaller-diameter
part of the leg, generally stationary and press-fit or clamped
into the crown, is the stanchion; and the larger diameter part
that fits over it is the slider. Some mountain bike downhill
forks have stanchions that extend up past the crown to a secondary crown at the top of the head tube. These are most
commonly referred to as double crown forks. At the lower
end of the blades are the two front axle holders known as fork
tips or fork dropouts. The steerer tube rises out of the crown
at the top of the blades and is normally hidden in the head
tube. It connects the fork crown to the headset.
The materials used in manufacturing the frame obviously
affect the way it feels. But as we said before, the length of the
tubes and the way they relate to one another — that is, the
frame geometry — play the major role in determining the way
a bike behaves.
There are two critical parts of frame geometry. The first is
the fork rake, which is the amount that the front axle is offset
from the centreline of the fork. The second is the bottom
bracket position, which is given either from the line drawn
between the front and rear axles (called the drop), or from
the ground (called the bottom bracket height). Other important aspects of the frame are the seat angle, which is the
smaller of the two angles formed by the seat tube and any
horizontal line, and the head angle, which is the smaller of
28
ILLUSTRATED BICYCLE MAINTENANCE
Classic Frame Anatomy
FRAMES
he two angles formed by the centreline of the head tube or
he fork and any horizontal line. All of these factors combine
o determine the bike's wheelbase, or the distance between
he axles of the two wheels.
History of the Bicycle Frame
The typical bicycle frame — sometimes called the diamond
frame because of its shape, but more commonly known as the
men's frame — has been around for more than 100 years, even
though it has seen competition from many other frame
designs. Ladies' and mixte frames may provide easier
mounting and dismounting because they don't have a top
tube, but the diamond frame still provides the best combination of rigidity, strength and light weight, and it is the predominant frame in use today.
Rigidity is important in a bicycle frame because a frame
that's too flexible wastes pedalling energy. Frames that do not
have a top tube are essentially incomplete from a structural
29
standpoint. To regain some of the strength lost because of
their poor structure, ladies' frames have traditionally been
constructed with heavy tubing. Not surprisingly, these bikes
have also been quite heavy in weight. In an earlier time, this
wasn't a major concern, since most men's frames were also
made from the same heavy, cheap tubing. But in recent years,
the bike market has changed considerably.
Technology developed over the past several years has
provided less expensive ways to manufacture high-quality
lightweight steel, aluminium, carbon and even titanium
tubing. At the same time, the demand for better-performing,
lighter bikes has greatly increased. As a result, most beginners
now expect to purchase a lightweight bike.
Because a ladies' frame can't be made with light-gauge
tubing, a few manufacturers offer mixte frames. These frames
can be made of light tubing because they are structurally
superior to the ladies' design. If you need a frame without a
top tube for clearance reasons, a mixte frame bike provides
The 1893 Crypto featured a two-speed gear mechanism (front) and weighed about 13 kilograms (28 pounds). Today's road bikes can weigh as little as half that.
30
ILLUSTRATED BICYCLE MAINTENANCE
much more rigidity and strength and is much lighter than a
ladies' frame bike. Even so, the traditional diamond frame is
still stronger and more rigid.
Today, smaller riders once forced to ride compromise
frames like the mixte design benefit from the increased availability of slightly smaller-than-standard, 650c size wheels (as
compared to the current standard, 700c size wheel) and
sloping top tubes (like those on mountain bikes). With the
650c size wheel, it is possible to have a lower frame for
standover clearance and a shorter top tube length without
the danger of excessive toe-overlap (when your foot at the
forward-most part of the pedal stroke extends past the
rear-most part of the front wheel, making steering difficult or
impossible).
The basic shape of the men's or diamond frame has
remained largely recognizable from the turn of the last century to the turn of the present one. Geometries have evolved
over this time, sometimes drastically and at other times more
subtly; and all despite the fact that the human body has hardly
altered in this time. The places we ride, however, have
changed over and over; and this has been the impetus behind
the changes in geometries.
EVOLUTION OF THE FRAME
The top tube on the ladies'
frame is replaced by a
second down tube, which
makes mounting and
dismounting easier but
eliminates much of
its structural strength.
The mixte frame is a
compromise between the
diamond frame and the
ladies' frame. Here the top
tube is replaced with twin
lateral tubes that run from
the head tube all the way
back to the rear axle.
Dramatic advances in materials technology, construction
techniques and the understanding of the mechanics of the
human body have also affected frame geometry. Cyclists can
now enjoy riding a single bicycle that deftly combines drivetrain efficiency, precise handling and a compliant ride.
Frame Materials
Even though you can't change the type of tubing used in
your frame, it can be very helpful to be able to identify it from
the tubing sticker displayed prominently on one of the frame's
main tubes. This helps you determine the value of the frame.
So, before you sink a lot of money into repairing or
upgrading an old bike, check to see if the frame is made of
tubing good enough to warrant the expense. And the next
time you spot an awesome-looking but unfamiliar brand
going for a great price at a garage sale, read the tubing sticker
so you can see whether it is a lemon or a bargain.
Legendary Steel
Even today, purists hold that all the technology that has gone
into new, exotic materials can't match the mystical ride
quality of a well-built steel-frame bicycle. Whether you agree
with this or not, there is one fact that
is beyond dispute: there are still a lot
of very good frames out there, some
old and some new, that are made out
of good old-fashioned steel. Here's
how you can determine whether
yours is a gem or just a rock.
Once there were only a handful of
tubing suppliers making all the tubing
used by bicycle manufacturers. At this
time, it was easy to gauge your bike's
quality by the tubing sticker. Today,
many bike manufacturers have taken
to designing their own proprietary
tube sets. What's more, manufacturers
LADIES' FRAME
of lower-priced bikes are now wise to
the tubing sticker and give fancy
names to what are essentially mild steel
budget bikes. So beware.We can't possibly list here every tubing brand and
type, but we can let you know what a
few of the most common, highquality tube sets are.
If there's no sticker on your frame
and the tubes are approximately 2 to
3 cm (1 inch) in diameter, then it's
probably made of mild steel. This
means the tubing walls will be very
thick and heavy. The frame will be
MIXTE FRAME
adequate in the utilitarian sense, but it
FRAMES
will have no appreciable value of its own. Frames that read
high-tensile', `high-ten', 'steel' or any similar term on their
stickers won't be much lighter or worth much more.
The first level of quality in steel bike frames generally
involves 'high-carbon' tubing, which may also be called by a
name particular to a certain brand.
Approaching the highest level of steel quality are steel alloy
tubes such as Reynolds 853, True Temper OX Platinum and
Columbus Foco. Frames made of these materials are substantially lighter and better riding than all high-tensile and many
high-carbon steel frames. Such a frame might be worth rehabilitating, but not if you have to pay a lot to do so.
But there's more to bike tubing than just its alloy. One way
that manufacturers market the use of a name brand of tubing
is to use the expensive tubing in just the three tubes of the
frame's main triangle. The tubing sticker of such a frame
might state the well-known alloy followed by the words 'three
main tubes' or 'Main Frame'. That makes a better frame than
one made of high-tensile steel, but not as good as one constructed entirely of high-quality alloy.
Another important tubing factor displayed on many stickers
butting. This refers to the process of making one section of
a tube with a thicker wall than another part of the same tube.
Single-butted tubing is usually found only in seat tubes, with
7 :ie thicker end placed in the bottom bracket shell to resist
2dalling forces. Double-butted tubing has thicker walls at
.nth ends.You can think of it as tubing that has two wall thickcsses: one thickness in the middle of the tube, and the other
the two ends. Triple-butted tubing is similar, except that it
:_as three gauges: the end thicknesses are not the same. Quadbutted tubing not only has two different endwall thicknesses
but the middle section also tapers from one gauge to another.
Triple- and quad-butted tubes, not often used anymore, are
designed to handle loads at the two ends of a tube that may be
substantially different, requiring different strengths.
Butted tubing offers a couple of advantages. First, butting
reduces weight by allowing lighter gauges to be used in the
centre sections of the tubes where there is less stress and
where there is no welding and filing, such as takes place at the
tube ends. (Both brazing and filing slightly weaken tubing.)
Second, butted tubes are more resilient, or have more give,
which means they provide a more comfortable ride. Don't
totally discount straight-gauge tubing, however. There are
places, such as tandem or mountain bike down tubes, where
it may be superior to butted tubing. In any case, even on
lightweight frames, butted tubing is found only in the three
tubes of the main triangle and in the fork's steerer tube.
-
Aluminium, Titanium and Composites
Nlaterials such as titanium, aluminium and composites made
from carbon, boron and Kevlar fibres are quite popular and
are becoming more affordable. Frames made from these
31
advanced materials offer lighter weight — and often increased
comfort. They're also amazingly corrosion resistant, which is
great for mountain bikes that frequently get doused with
plenty of water while crossing streams.
Today, aluminium is the most popular material for bike
frames. Advantages include a slight weight savings, no rust
problems and excellent rigidity, which ensures that every
pedal stroke goes directly into forward motion and isn't lost
in frame flex.
As with steel, aluminium tubes can be butted to save
weight while putting strength where it's needed. Beyond
butting, though, aluminium tubes can also be formed into
radical shapes that help it reach new levels of performance
and at the same time make for a more comfortable frame than
believed possible in years past. Aluminium's main drawback is
its relatively short fatigue life. Unlike steel, carbon or titanium, aluminium fatigues a little bit every time the frame
flexes even just a small amount. It takes years before the
average rider can fatigue an aluminium frame enough for it
to develop into a problem, though.
Carbon is one of the most interesting frame materials
because there are so many ways it can be used.You'll see it in
tube form, as on Trek OCLV frames, and in monocoque
form, as on Kestrel or older Trek 'Y' frames. The former
resembles other bike frames. The latter has a striking onepiece, moulded look, resembling the body of a race car.
Carbon is a unique material. It starts as a fabric, and the
frame designers custom-build each tube or frame section by
precisely adding or removing fibres to get the strength and
compliance exactly where it's needed. This level of 'tube
tuning' isn't possible with metal tubes, and it has produced
sonic of the lightest bicycle frames in the world.
Nevertheless, to many cyclists, titanium stands as the dream
material for bike frames. From an engineering standpoint,
carbon holds more promise, but titanium has a better reputation for durability and an amazing ride quality. Titanium feels
alive and springy, like there's energy inside the tubes. It also
compares with carbon, weight-wise, and enjoys excellent
corrosion resistance.The only negative is that it's costly.
The Basics of Frame Geometry
Depending on the use for which a bike is designed, the seat
angle, head angle, fork rake, chainstay length and bottom
bracket drop (you'll often hear it called B/B drop) are varied
within a narrow range of values. Small differences in the
dimensions of any of these factors can make a great difference
in the performance of a bike and in your performance on it.
The seat angle's primary function is to determine your leg
position in relation to the crankset, which can influence the
way you pedal. In general, steeper angles are better for highcadence spinning, while shallower angles are more conducive
to muscling a bigger gear at slower cadence.
32
ILLUSTRATED BICYCLE MAINTENANCE
The head angle is instrumental, along with the fork rake,
in determining how your bike handles. This includes stability,
whether at cruising speed or in high-speed descents, and cornering capability.
Generally, performance-orientated bikes like road racing
bikes or cross-country mountain bikes will have a steeper head
angle than will touring bikes, downhill and freeride bikes or
other bikes built for all-day comfort on longer rides.
To decide what's right for you, think about your favourite
road or trail. Is it a fast, windy patch of mountain road or a
twisty singletrack in the hills?You'll probably be happiest with
a steeper head angle. On the other hand, do you love
spending hours working your way deep into the backcountry
or taking in the sights on a country lane? Is your idea of bliss
finding the steepest, most treacherous descent around? In
these cases, you'd likely be best served by a shallower or less
steep head angle.
But head angle isn't the be-all and end-all of a bicycle's
steering feel. The head angle, fork rake and wheel diameter all
combine to create a dimension called trail, which is a critical
determining factor in a bike's steering characteristics.Trail is calculated by following an imaginary line drawn through the centre
of the head tube to the ground. The distance from where this
line intersects the ground to the point directly below the axle,
measured horizontally, is the trail measurement.
Put most simply, a longer trail measurement is more stable
and a shorter one handles more quickly Since trail is nearly
impossible to measure except on paper, and because changing
tyre size can change the dimension, most frame builders report
head angle and fork rake only on their geometry tables.When
comparing bikes built for similar purposes, using similar size
wheels and tyres, this is enough information to allow you to
make an informed decision about handling characteristics.
Chainstay length also affects the way a bike rides. Shorter
chainstays, like those on road racing frames, can make a bike ride
a bit more harshly but with less flexing in the rear triangle,
which is especially important in hill climbing and sprinting.
Shorter chainstays also decrease a bike's wheelbase, and the
shorter that is, the more nimble and quick the bike feels. Loaded
touring bikes, on the other hand, need longer chainstays for heel
clearance with rear panniers, or rack bags.Those long chainstays
also provide the more stable ride that a tourist usually wants.
A larger drop, or a lower bottom bracket height, is also
often found on loaded touring bikes. The lower the bottom
bracket, the lower the saddle and the lower the centre of
gravity (CG) for the combination of the bike and its rider. A
bike with a lower CG is more stable without losing any handling quickness. That's a desirable characteristic for most
bikes. Unfortunately, most racing events involve cornering,
and many racers like to pedal out of corners. For such riders,
higher bottom brackets are necessary for the clearance needed
between their pedals and the road. Tight-cornering criterium
Manipulating tube diameter, wall thickness and tube shape put strength and
rigidity where they are needed and reduce weight where they are not.
racing bikes usually have high bottom brackets, while traditional road racing bikes fall somewhere in between. Mountain
bikes have higher bottom brackets, which helps in clearing
obstacles and in pedalling over cluttered terrain.
A similar trade-off between low-CG stability and ground
clearance figures into the various frame designs for mountain
bikes. Once you get off the beaten path, you can expect to
encounter some large rocks and fallen trees, not to mention
deep weeds.
With these general observations in mind, let's take a closer
look at the main types of bicycle use and the frame geometry
appropriate to each.
Road racing bike. The frame of a racing bicycle is designed
for stability at high speeds, easy cornering, quick steering
response and a stiff, efficient ride that minimizes energy losses.
As a direct result of these virtues, the racing bike usually has
poor low-speed stability, handles worse if any load is carried on
the frame, requires constant attention to maintain a straight line
and very efficiently transmits even the tiniest bump in the road
;traight to your body. You can identify a racing frame by the
following measurements.
Seat angle: 73 to 74 degrees. Add 1 degree to that range
for frames with a seat tube smaller than 54 cm (21 inches)
(measured from the centre of the bottom bracket to the
top edge of the seat lug) and subtract 1 degree for frames
larger than 60 cm (24 inches).
Head angle: 73 to 74 degrees. Subtract up to 2 degrees
from that range for frames smaller than 54 cm (21 inches)
FRAMES
and add 1 degree for frames larger than 60 cm (24 inches).
Fork rake: 38 to 45 mm (1% to 1% inches) for a 73-degree
head angle. Subtract or add 3 mm (4 inch) for every
degree of head angle greater or smaller, respectively.
Chainstay length: 40.5 to 42 cm (16 to 16% inches).
Drop: 60 to 75 mm (2% to 2% inches).That equals bottom
bracket heights of 28 to 26.5 cm (11 to 10% inches).
Road sport touring bike. Sport tourers are the midsize sports
cars of the biking world.They're not all-out racers, but they're
not loaded touring bikes either. They can carry a load with
racks and small panniers, but not too much. Their major
attribute is their stable handling, which is predictable, if a little
slow by racing standards. Sport tourers just want to have fun,
so to speak, and can do just about anything well enough for
you to enjoy it. Look for the following dimensions.
Seat angle: 72 to 73 degrees. Add 1 degree to that range
for frames with a seat tube smaller than 54 cm (21 inches)
(measured from the centre of the bottom bracket to the
top edge of the seat lug) and subtract 1 degree for frames
larger than 60 cm (24 inches).
Head angle: 72 to 73 degrees. Subtract 1 degree from that
range for frames smaller than 54 cm (21 inches) and add
1 degree for frames larger than 63 cm (25 inches).
Fork rake: 43 to 55 mm (1% to 2% inches) for a 73-degree
head angle. Subtract or add 3 mm (4 inch) for every
degree of head angle greater or smaller, respectively.
Chainstay length: 42 to 44.5 cm (16% to 17% inches).
Drop: 68 to 78 mm (2% to 3 inches). That equals bottom
bracket heights of 27.5 to 25.5 cm (10% to 10 inches).
Loaded touring bike. The pack mules of the two-wheel road,
loaded touring bikes exhibit great stability and straight-line
tracking, even with up to 18 or 22 kg (40 or 50 pounds) of
cargo.You can watch the scenery from aboard one of these
without the constant fear of either meandering off the road
or straying into traffic lanes. In addition, they are comfortable
over rough roads and also come with gearing low enough to
allow you to climb over any mountain. This all adds up to a
bike that's perfect, loaded or not, for those whose main
interest is being there, rather than speeding on by.
Seat angle: 71 to 72 degrees. Add 1 degree to that range
for frames smaller than 54 cm (21 inches).
Head angle: 71 to 72 degrees. Subtract 1 degree from that
range for frames smaller than 54 cm (21 inches) and add
1 degree for frames larger than 63 cm (25 inches).
Fork rake: 50 mm (2 to 2% inches) for a 72-degree head
angle. Subtract or add 3 mm (% inch) for every degree of
head angle greater or smaller, respectively.
Chainstay length: 43 to 45.5 cm (17 to 18 inches).
33
Drop: 8 cm (2% to 3% inches).That equals bottom bracket
heights of 27.5 to 26 cm (10% to 10% inches).
Mountain bike. Whether you want to explore deep into the
backcountry or you seek the rush of a woodland rollercoaster
ride, the mountain bike can take you there and back. Mountain
bike design has become more and more specialized over its 20some year evolution.Walking into your local bike shop, you may
hear things said like 'Cross Country' (or `XC'), Treeride',`DH'
(or DownhilF), 'Epic', Tnduro% 'Jump Bike', 'Two-Niner',
'Trials', ' Marathon' or any number of other terms for what we
all used to just call mountain biking. But the root formula is still
the same: wide, sturdy wheels and a straight (or slightly rising)
handlebar suit these bikes to life on dirt (or rocks, or
Logs... you get the idea).
Mountain bikes are equally as comfortable around the
town, too. In fact, it's been said that only about 10 percent of
all mountain bikes sold are purchased with the intention of
riding off-road. Wide, deeply treaded tyres are far better suited
:0 take the knocks of curbs, potholes, sewer grates, broken
;lass and other roadside debris than the slender, lightweight
wheels of a road racing bike.And the mountain bike's upright
riding position allows a better view of traffic and pedestrians
around you.
Most mountain bikes you see on the showroom floor will
,till be of the cross-country (XC) variety. The XC bike is the
.-nost direct descendent of the classic mountain bike we all recagnize. It's an all-purpose machine that is as comfortable on the
Tail with a pair of knobbed off-road tyres as it is cruising
around town on a smoother set of street rubber. Such is the
nountain bike's greatest appeal: its upright riding position and
aalance of weight and strength make it the ideal 'one bike' to
awn for most casual cyclists. XC bikes can be had fully rigid
,'no suspension in front or rear), front-suspended (also called
hardtails' for their lack of rear suspension) or dual-suspended.
Typically, front-suspended models will have a suspension fork
with 63 to 80 mm (2% to 3 inches) of travel, and dual-suspended
nodels will have between 80 and 100 mm (3 to 4 inches) of
Tavel both front and rear.
When selecting a mountain bike, most shops will recommend you have 8 cm (3 inches) or more of standover clearance
;the amount of clearance between you and the top tube when
straddling the bike, flat-footed). Not having enough standover
:learance can be downright painful should you need to put a
bot or two down on rough terrain. If you're buying the bike
:o use only for commuting, running errands around town and
o ccasional riding along dirt roads or sandy beaches, something
with a longer top tube may suit your needs better.
Seat angle: 70 to 73 degrees. Add 1 degree to that range
for frames smaller than 50 cm (19 inches).
Head angle: 69 to 72 degrees. Subtract 1 degree from that
34
ILLUSTRATED BICYCLE MAINTENANCE
of high drops and steep descents, but they're also expected to
climb and steer well at low speeds. The geometry of freeride
bikes leans towards that of downhill bikes, but with suspension travel in the range of 15 to 20 cm (6 to 8 inches), slightly
lower B/B heights and marginally steeper head angles to
sharpen handling.
Jump bike. Jump bikes are generally very small-framed hardtails with front suspension ranging from 10 to 15 cm (4 to 6
inches). The frames are built to handle the rigors of jumping
and other stunts and have clearance for extra-wide tyres to
absorb impact.
Mountain bikes are sometimes likened to the SUVs of the bike world. Wide,
durable tyres and an upright riding position make them well suited to getting
around downtown as well as negotiating off-road trails.
range for frames smaller than 50 cm (19 inches) and add
1 degree for frames larger than 60 cm (23 inches).
Fork rake: 43 to 50 mm (1% to 2 inches).
Chainstay length: 40.5 to 43 cm (16 to 17 inches), or
shorter (if you can find it) for really steep climbing.
Drop: 30 to 50 mm (1X to 2 inches). That equals bottom
bracket heights of 30.5 to 28.5 cm (12 to 11YI inches).
All rules go out the window when you stray from the
pure XC bike. We'll break down a few 'typical' speciality
bikes for identification purposes.
Enduro bike. A dual-suspension mountain bike largely similar to the cross-country bike but with more suspension travel,
usually in the range of 100 to 130 mm (4 to 5 inches), and a
slightly shallower head angle for stability on long rides deep
in the backcountry.
Two-Niner. Based around a 29-inch-diameter tyre, Twoniners are built for speed. The larger-diameter wheel rolls
more smoothly over uneven terrain than the standard 26-inch
wheel at the expense of some agility. These bikes rely on a
longer-than-usual top tube coupled with a shorter-than-usual
stem to minimize toe overlap, but they maintain the relationship between crankset, saddle and handlebar similar to that of
a smaller-wheeled bike.
Downhill bike. With as much as 25 cm (10 inches) of suspension travel, front and rear, downhill bikes can roll over
almost anything short of a brick wall. Very shallow head
angles and high bottom brackets make these bikes lumber
along on smooth ground and their weight makes climbing
seem futile.
Freeride bike. Freeride bikes have the toughest job of all
mountain bikes in my opinion.They need to handle the abuse
Trials bike. Observed trials is a form of mountain bike competition that focuses on obstacle negotiation. Trials bikes have
ultrashort chainstays (as short as 38 cm/15 inches), high
bottom brackets and very low top tubes to help them up and
over boulders and logs as well as manmade obstacles and
through streams — often moving only inches at a time.
Cyclocross. Cyclocross is a form of competition where bicycles that appear to the untrained eye to be road racing bikes
are raced off-road. In a cyclocross or 'cross race, riders negotiate a short, tight course over varying terrain with occasional
barriers that are intended to make the racers dismount and
run with their bikes for short distances.As a result, 'cross bikes
are designed and built to be as sharp-handling and lightweight
as their road racing counterparts, but with the added demands
for durability to survive this intense sport.
Hybrid bike. Part mountain bike and part touring bike is the
nearest way to describe the hybrid bike. The frame geometry
is closely related to that of the touring bike, with relaxed
angles and clearance for wide 700c tyres.The mountain bike's
donation to the equation is its flat or rising handlebar and
doping top tube to make for a comfortable, upright riding
position and to make mounting and dismounting easy.
Frame Maintenance
Now that you're fitted correctly to your machine and you
understand its design and function better than ever before,
what maintenance can you perform to ensure the long life of
your bike's frame? A lot more than you might think.
Kicking corrosion. Besides accidents, the greatest enemy
your frame may face is corrosion. You needn't worry about
:his much if you ride an aluminium, carbon or titanium
Frame. But if yours is steel (if you're not sure, check it with a
magnet), take care. If you sweat a lot on your bike while you
ride it, either indoors or out, thoroughly rinse it off as frequently as is practical. Salt deposits form in any kind of
FRAMES
corner, especially underneath clamps, and continue the
process of corrosion, even if the bike is dry. Braze-on parts
contribute less to this severe problem than clamp-on parts,
but they still trap unwanted salt. Salt can affect aluminium,
carbon and composite (made of two or more different materials, like carbon tubes mated to aluminium lugs, for example)
frames and components, too.
Prompt attention to your bike after sweaty rides or workouts on rollers or indoor trainers means a thorough, gentle
water rinse. Don't use high-pressure hoses or concentrated
spray patterns because they'll force water, and maybe also dirt,
into your bike's bearings.
Clear silicone-rubber bathroom caulk can help keep sweat
and water out of the inside of your hike's frame. Unless the
locknut on your headset has an 0-ring seal, sweat can seep
down the sides of your stem into the steerer tube. The
resulting corrosion can sometimes require the use of a
hacksaw to remove the stem from the steerer. A thin bead of
clear caulk around the base of the stem (wipe away the excess)
will prevent the problem.
If you ride in the rain even occasionally, the same caulk
;-catment applied to the junction of the seat tube and the
,
eatpost will prevent water thrown up under your saddle from
leaking into your seat tube and collecting in your bottom
bracket. Even if you have a shield protecting the bearings, the
threads of your bottom bracket shell can rust — a situation that
could eventually make it difficult to keep your bottom
bracket cups tight. It's a good idea to remove your seatpost
periodically and tip the bike upside down to drain it.
While the best defense against corrosion is to prevent
moisture from entering your frame tubes, it is also a good idea
to help fight corrosion from the inside. Anytime you have
y
our seatpost out of the frame or your headset or bottom
bracket dismantled for an overhaul, use the opportunity to
spray or swab a rust inhibitor such as WD-40 inside the
exposed tubes.
Painting over chips. Paint chips can allow rust to start even
on a dry, salt-free frame. To prepare the surface for touch-up
paint, don't sand the chipped area except to remove rust. Most
manufacturers treat their frames' bare surfaces with a very thin
phosphate coating that inhibits rust; sanding will remove it.
Instead of sanding, use a solvent, such as lacquer thinner, to
clean any oil from the chipped area.Then cover the chip with
one or more coats of almost any type of paint that matches
your bike's original colour. If rust has already reared its ugly
head through the hole in your frame's finish, use fine sandpaper to remove all of it before you touch up the frame. Don't
expect miracles: the purpose of your touch-up is to minimize
rust damage to your frame until you have it repainted.
There are some other steps worth taking to protect the
paint on your frame. Because the chain is close to the right
35
rear chainstay, it can slap against it when you hit bumps. This
makes a metallic clank sound and can lead to chipping paint
on the chainstay. A simple way to protect the stay and muffle
the chain slap is to put a vinyl or foam chainstay protector
over the stay. These are adhesive-backed and are available at
your local bike shop. For more complete protection, you can
wind electrical tape or an old inner tube over the entire stay.
Chainstay protectors made of neoprene, the same material
used to make surfers' wetsuits, also do an excellent job of protecting your chainstay and quieting chain slap. When using
one of these, though, you should make it part of your maintenance routine to remove it after rainy rides, as they can
absorb moisture and hold it against the frame.
Another good way to protect paint is to stick tape beneath
cables where they rub the frame, such as Shimano STI cables
that strike the frame by the head tube. This will prevent them
from wearing a hole in the paint. Just cut a small oval of tape
(get clear tape or tape the same colour as your frame so it's
not noticeable) and stick it on under the housing.
To stop the rattling and resultant paint scratches you might
get from bare cable sections (such as the rear brake cable
under the top tube), install cable 0-rings. Shops should have
these. These tiny rubber doughnut-shaped 0-rings slip over
the cable and prevent it from vibrating when you're riding.
Fixing bends. Obviously, the best way to help your frame last
is to avoid twisting it out of shape in an accident.A good bike
frame has considerable resilience but cannot be expected to
regain its original shape after being wrapped around a tree. If
you're unlucky enough to crash and bend your frame or fork,
take it to a mechanic for evaluation. A shop with
alignment tools can sometimes straighten metal frames and
rigid (non-suspension) forks enough that they still ride fine.
Bent suspension forks can often be repaired by replacing the
Damaged parts.
Repairing dents. Sometimes a crash dents a frame tube.
Though unsightly, these dents rarely weaken the frame much.
If you can't stand looking at a dent and if you have a steel
:came, you can have a framehuilder fill the dent with brazing
:material. After painting over it, for all practical purposes, your
'rame will be as good as new.
Unbending a derailleur hanger. Another type of frame
1amage that often occurs in a crash is a bent rear derailleur
ganger. This can also happen if you shift into the spokes or
trop your bike on its side. Both cause the derailleur to get
Dulled forcefully inward. Because the derailleur is attached to
tab built into the bottom of the right-hand dropout, the tab,
:00, gets bent, sometimes severely.
The proper way to repair a bent hanger is to use something called a hanger alignment tool that has a feeler and
36
I
CLE MAINTENANCE
references the hanger against the rear wheel, keeping the
hanger perfectly aligned. This is especially important for
modern indexing systems that allow for little margin of error
in the alignment of the derailleur and cogs. In a pinch,
though, or on an older bike with friction shifting, you can
often repair a bent hanger by removing the rear derailleur and
pulling the hanger straight with an adjustable spanner (set the
jaws to just fit over the hanger). On a ride, it's unlikely that
you or your friends are carrying a hanger alignment tool or
large adjustable spanner. In these cases, use the rear wheel to
bend it by removing the quick-release, screwing the axle into
the hanger, installing the quick-release and using the wheel to
bend the hanger back close enough to get you home.
Sometimes, the accident tears the threads in the hanger
and if you try to remove the derailleur, you'll remove the
threads with it. Fortunately, there's a clever fix even if you
have a frame with a one-piece hanger that's part of the
dropout. A threaded piece that fits into the damaged hole to
restore it is available. All you have to do is bend the hanger
straight and install this part, and the frame will be as good as
new After such a home repair, it is always a good idea to have
a shop with alignment tools check your work because the
shifting can suffer if the derailleur alignment is off.
Bending the hanger and repairing damaged threads are
easier to do and more likely to be done successfully on a steel
frame than on an aluminium frame. Because of this, most
aluminium frames now use a replaceable hanger that can
simply be removed and disposed of in the event of a bad bend
or break. These replacements are not expensive and riders of
aluminium bikes should pick one up and keep it in a takealong tool kit.
Dealing with loose water bottle mounts or stuck screws.
One possible glitch on aluminium and composite frames is
loosening of the water bottle mounting bosses, or getting a
water bottle screw stuck in the boss.These fittings are pressed
into the frame at the factory and should stay fixed. If they
start rattling or spinning in the frame, making it impossible
to remove the screw, take your frame to your dealer or a shop
that carries your brand of bike. They should have the factory
tools to remove a stuck screw, reseat the boss and stop the
rattling.
Steadying speed wobble or shimmy. A handling glitch that is
often blamed on the frame is speed wobble, the tendency of
a bike to shake violently at fast speeds on a downhill. Obviously, this is a dangerous problem, and every cyclist should
know what to do if it happens. Though it may not always
work, try clamping your knees together on the top tube to
stop the wobbling.
Speed wobble is usually related to component adjustments
(faulty or improperly installed tyres, a loose headset or untrue
or under-tensioned wheels) and sizing mistakes (usually a
too-high seat). Check these things first and test-ride the bike
to see if the wobble goes away.
If the wobble doesn't stop, there's another possible culprit:
a frame made of tubing that is too light for the person using
it. This might happen if you purchase a used custom frame
that was built for someone else, or if you're on the big side,
say, over 180 cm (6 feet) tall and 90 kg (200 pounds) but
riding an ultralight bike (always test-ride before buying). In
this case, the best bet is to sell the bike.
Waxing the frame. An occasional waxing when your bike is
clean and dry helps its appearance and improves your chances
of staying ahead of rust. There are many bike-specific polishes
on the market, such as Pedro's Bike Lust, that are formulated
to be kind to the high-quality paint finishes found on many
custom bikes. For titanium frames, a wipe-down with an
all-purpose furniture polish will keep your frame looking
showroom new (and lemony fresh).
Basic Frame-Alignment Checks
Alignment of the bicycle frame is important because it affects
many things. For example, if the fork is slightly bent, taking
your hands off the bar may result in the bike steering off the
trail. Or if the rear triangle isn't aligned with the front triangle, the chain may fall off the chainrings every time you
shift onto the small chainring.
Frame alignment is usually spot-on when a bike first
comes from the bike shop.When a mechanic assembles a bike,
he looks for signs of alignment problems and makes adjustments to the frame as needed. Or if the frame is really out of
whack, he'll return it to the manufacturer.
Unfortunately, just because a frame is straight when you
buy it doesn't guarantee that it will remain so. Accidents,
abuse or even just dropping the bike on its side can lead to
alignment problems if the impact is hard enough.
Some shops have impressive alignment tables and fixtures
For precisely measuring and straightening frames to very
exacting standards. If you bend a frame severely, it makes sense
:o use their services. Keep in mind that a bent frame cannot
always be repaired if the damage is serious, and not all types
Df frames can be aligned. Signs of serious damage include
wrinkles in frame tubes that indicate the tube has been
auckled, and cracks that mean that the frame will likely break
;oon if you continue riding on it. Don't mess with that type
Df damage. It's best to replace the frame.
Frame material makes a difference, as well. Steel frames are
nuch more easily repaired than most titanium, carbon or
welded-aluminium frames. If you find a titanium or weldediluminium frame is out of alignment when you check it, take
t to a bike repair shop. It may be a warranty issue. In most
rases, it's impossible to make anything but minor corrections
FRAMES
-1 these types of frames, and it's best to let a professional
-aechanic handle the work.
Frame spacing. For the wheels to slide smoothly in and out
of the frame, the widths of the front and rear forks should
match the widths of the wheels (measured from the outer
Ages of the two axle locknuts).To check fork width, measure
tom the inside surface of one dropout to the inside surface
of the other. Front forks should measure 100 mm wide. Rear
forks should measure 120 mm for five-speed rear wheels, 127
for six- and seven-speed wheels, 130 for eight-, nine- and
ten-speed road wheels, and 135 for mountain bike wheels.
If the measurement is off by more than 2 mm, it's usually
still relatively easy to install and remove the wheel. But if the
measurement is off and it's a struggle to get the wheels in, not
only are the dropouts probably too narrow but it could also
be that they've been bent out of parallel to each other. If that's
the case, take the frame to a shop and to have the dropouts
aligned. Shops have special tools that make this job easy. Not
only will fixing the dropouts ease wheel installation and
removal, but also it will eliminate uneven pressure on the axle
that often leads to broken axles.
Alignment of the rear triangle with the front triangle.
shifting problems are often related to improper chainline,
vhich occurs anytime the crankset and the cassette cogs are
out of alignment. Ideally, an imaginary line would bisect the
chainrings and the cassette. If the rear triangle isn't correctly
aligned with the front triangle, this isn't the case, and it results
in a misaligned chain and derailleurs, which causes shifting
problems.
Here's an easy way to check the alignment of the rear end.
First, do the frame spacing check, as this affects rear-triangle
_lignment. Next, get a piece of fine but strong thread or
fishing line. Tie it to the right rear dropout in such a way
that you can repeat the exact placement on the left dropout.
Run the thread around the head tube of the bike and pull
back to the left dropout. Pull the thread so it's taut and tie
in exactly the same position in which you tied it on the
other side.
You should now have a piece of thread running from the
:ear of the bike, around the head tube and back to the rear of
the bike. Now, hold one end of a ruler against the seat tube
of the bike, extending it out so that the thread rests on the
ruler's gauge and you can read the measurement. Jot the
number down, then repeat the measurement on the other
side, making sure that you hold the ruler the same way that
you did on the first side. The two numbers should match if
the rear triangle is aligned correctly with the front triangle.
If they're off by more than 4 mm and you're experiencing
problems with shifting or the chain falling off, have a shop
align the rear end.
37
Wheel tracking. This alignment check determines whether
the front and rear wheels are tracking in line with each other.
To do this check, remove the tyres and tubes and reinstall the
wheels, taking care to centre them in the fork and rear triangle. Hold one end of a 150-cm (5-foot) straightedge or a
straight piece of wood or metal against the front wheel so that
it touches two points on the rim.Then swing the straightedge
up (or down, if you're working on the bike when it's upside
down) towards the rear wheel. If the wheels are in line with
each other, the straightedge should contact two points on the
rear rim, too.
These alignment checks aren't necessary unless you suspect
problems. Most modern bikes are built to fine standards. But
if you have a problem or you crash hard and are concerned, a
careful inspection could put your mind at ease or alert you to
the need to have a professional repair the frame.
Repainting a Frame
Steel frames occasionally require repainting. You may also
want to get an aluminium, carbon or titanium frame
repainted if the finish gets chipped. A repaint in your chosen
colour not only looks good but also provides an opportunity
to stop any ongoing corrosion. On steel frames, repainting
gives you an excuse to acquire any braze-on fittings you've
been wanting.
We don't recommend painting a bike yourself. It's a big job
that is best left to professionals. If you can't locate either a
framebuilder or a bike-finishing specialist in your area, check
with the nearest bike shop. People there will probably be able
to point you towards a reputable refinisher.
When arranging for refinish work, make sure that the firm
has experience with the type of frame you're having redone.
Thin-wall metal tubes need to be stripped carefully so as not
to remove any of the tubing material. Carbon frames are usually not stripped, just lightly sanded before being refinished.
The refinisher should know all about these things.
As for types of paint, baked enamels and catalyzed enamels
provide the most durable topcoats, whereas lacquers should
D e avoided because they chip easily. Imron, a single-layer paint
once favoured for its durability and ease of application, is not
often used any more. Instead, multilayer paint jobs using a
:olour coat followed by a protective clear coat are most often
used now, giving colour saturation and depth that can not be
luplicated by single-layer paints.
A Worthy Investment
Your bicycle's frame can accompany you for many years and
:ens of thousands of miles if given proper consideration and
:are. Deal with paint chips promptly; don't allow perspiration
or road salts to accumulate; don't abuse your bike by riding
7ecklessly and jumping a lot; store it inside, out of the weather;
Ind once in a while treat your frame to a new paint job.
CHAPTER 3
Suspension
The subject of bicycle suspension could easily fill its own
book.What once was only a tool of mountain bike racers and
the most avid of enthusiasts is now commonplace on nearly all
types of bicycles, not just mountain bikes. Hybrid bikes,
recumbent bikes, tandems and even some road bikes now
benefit from a little extra cushion. Still, the mountain bike is
where the modern era of bicycle suspension got its start and
remains where manufacturers turn when time comes for
refinement. This chapter will serve to introduce you to the
concepts and basic design principles of many of the most current suspension systems.
We begin with the basics
While most may recognize that air-filled tyres will compress
and rebound with changes in the terrain, what may not seem
obvious is that every part of any bicycle — suspended or not —
absorbs shock in some small amount. Handlebars, wheels,
seatposts, saddles, even the most rigid aluminium racing frames
have a measurable amount of flex or give that equates to a
shock-absorbing property. While all these things working in
concert effectively smooth out a rough patch of road, as the
going gets rougher you'll need a little more to stay on track.
Beyond making your ride more comfortable, suspension
plays a vital role in your bike's handling on rough terrain. A
nonsuspended or 'rigid' bike will tend to bounce over obstacles like rocks, roots and potholes, relying on the rider's skill
to keep it pointed in a safe direction. By introducing a shock
absorber into the equation, the wheel will read and react to
changes in terrain on its own, leaving the rider with a little
less to think about on the road or trail. This peace of mind
while riding comes with a price, however. Suspension frames
and forks require regular maintenance to ensure that they
continue to perform effectively.
Suspension Forks
With a few rare exceptions, suspension forks on bicycles
today are of the telescopic variety. This means there are
two main components to each leg of the fork, one that slides
over the other. The stationary part of the leg is called the
stanchion; the moving part is the slider. The stanchions are
press-fitted into a crown that also holds the steerer tube.These
three tubes clamped into the crown give it its other common
name, the triple clamp.
What appears to be simplistic on the exterior is a marvel
of technology in its interior. The internals of suspension forks
are closely guarded secrets through the development of new
models. Springs, pistons, valves, air and oil chambers are all
carefully engineered to perform at the highest level while
minimizing weight and maximizing durability. It's a delicate
balancing act to say the least. Essentially, though, all telescoping suspension forks rely on two basic principles.
Bounce
First and most obvious is the spring. This is what gives the
fork the ability to absorb an impact and return to absorb
another. Springs used for bicycles come in three types: coil,
air and elastomer. The coil is readily recognizable as a spring.
Usually made from steel wire of varying gauge or thickness,
the wire is wound into a coil that compresses with a given
amount of force.
Less obviously, air can also be used as a spring. The most
recognizable use of air as a spring is in your bike's air-filled
tyres. In your suspension fork, air can be used as a spring by
inflating a sealed chamber inside the fork. Air offers two benefits over steel coils. For one, air is light. Also, incrementally
changing the pressure inside the fork allows a great range of
adjustment for different riders that can be made without disassembling the fork (as must be done to change a coil spring).
The last type of spring is the elastomer. Elastomers were
used frequently in the early days of mountain bike suspension, but are much less common now. Made of a urethane
material, elastomers are light, simple and relatively low-maintenance. However, as suspension travels have increased over
the years, elastomers have become less and less viable because
a stack of elastomers needs to be much longer than a coil
spring or air chamber to achieve the same amount of travel.
Control
The second basic principle of suspension is damping.
Damping is the ability to control the speed of compression and
rebound of the fork. An unchecked spring will compress and
rebound too quickly, making your bike bounce like a pogo
stick. To control this motion, most performance suspension
forks use a volume of oil and a piston that flows through it. By
changing the size of the hole in the piston and the weight (or
viscosity) of the oil, it is possible to slow down the motion of
the fork to a useable rate.
There are two common types of oil dampers being used
today. An open damper uses one volume of oil to handle the
duties of lubricating the fork's slider bushings and stanchions
40
ILLUSTRATED BICYCLE MAINTENANCE
Anatomy of a Suspension Fork
■ STEERER TUBE
BRAKE POST
LOWER CASTING
(SLIDER)
SUSPENSION
ROCKSHOX SID
and to flow through the damper to control
compression and rebound speed. A cartridge
damper incorporates a sealed tube in which
the oil and damper piston work, relying on a
separate volume of oil or grease to lubricate the
slider bushings and stanchions. Each has a benefit
and a drawback. A cartridge damper remains sealed
inside the fork, requiring service less frequently than an
open damper, which can become contaminated as dirt
makes its way past the dust wiper and main oil seal at the
top of the slider leg. But when a seal does wear out or split
on a cartridge damper, it won't be instantly obvious why
damping has been lost. The seals on open systems can be
viewed and inspected for 'oil weeping' without disassembly,
but the greater volume of oil used in these designs makes
them slightly heavier in most cases.
Keep It Clean
Manufacturers' recommendations vary, but most will agree
that you should visually inspect your fork for signs of oil
weeping or stress before every ride.Your fork should be disassembled and cleaned after every 50 hours of riding in fair
conditions or as frequently as every 25 hours of riding in wet
or muddy conditions. A complete overhaul of the fork,
including replacement of seals, wipers and slider bushings, is a
good idea every 200 hours. Of course, when there are signs
of oil leaking from the fork, the offending seals should be
replaced immediately before performance begins to suffer.
Maintaining your suspension fork is relatively easy with
the right tools. The most important one to have is a service
manual specific to the model of your fork, provided by the
manufacturer. If you don't have your manual, you may be able
to track one down at your local bike shop or by visiting the
TROUBLESHOOTING
These maintenance recommendations are general guidelines.
You should check your owner's manual for your suspension
manufacturer's specific, recommended maintenance schedule.
DO WHAT
Check air pressure for
air-sprung shocks
WHEN
Before every ride
Clean and inspect, visually
Before and after every ride
Check torque and tightness of
rear suspension pivots
Every 10 hours of riding
Change oil and replace seals
Every 50-100 hours, or if a
leak develops
Complete fork rebuild
including new bushings
Every 100-200 hours, or if
excessive play develops
Replace suspension pivots
Every 100-200 hours, or if
excessive play develops
FOX FORX
TALAS RLC
41
MARZOCCHI 888 MANITOU SHERMAN CANNONDALE
BREAKOUT
LEFTY
A wide variety of suspension forks exists to match every riding style.
Web site of your fork's manufacturer. Here are a few of the
most common:
Cannondale, www.cannondale.com
Manitou, www.answerproducts.com
Marzocchi, www.marzocchi.com
Rockshox, www.rockshox.com
Suspension Stems
Though less common today, suspension stems offer a light,
simple and inexpensive option for adding comfort to the
front of a bike. Since frame geometries had to be modified
with the advent of suspension forks, suspension stems could be
used to upgrade older bikes without worry of adverse effects
to the bike's head angle, causing slow or floppy steering.
Rear Suspension
Sometimes it seems there are as many unique designs of rear
suspension as there are trails to ride. From the simplest softtail design, yielding an inch or so of travel, to sophisticated,
computer-designed linkages allowing 20 to 25 cm (8 to 10
inches) or more of wheel movement, there's a dual suspension
mountain bike to suit any riding style.
Rear-Suspension Basics
Swingarm rear-suspension design is complicated by the presence of the chain, which pulls on the rear wheel. If the rear
axle doesn't move at a right angle to chain force, then these
pulses will compress or extend the drivetrain.This means that
pedalling will raise or lower the rider with every stroke
(`bob'). Conversely, the rider will feel the crankarms slow or
quicken every time the rear wheel hits a bump and compresses the suspension (`biopacing').
Another unintentional input that rear-suspension designs
have to fight is the tendency for braking forces to try to freeze
the Swingarm in place (`brake jack'). Brake jack is of great
concern for racers looking to shave precious seconds. Still, for
enthusiasts seeking top performance, certain rear-suspension
designs are less susceptible to brake jack than others.
42 ILLUSTRATED BICYCLE MAINTENANCE
What's Inside Your Suspension Fork
AIR SPRUNG
COIL SPRUNG
Mountain bike suspension forks have borrowed heavily from the motorcycle
OPEN DAMPER
CLOSED DAMPER
referred to as elastomer saw widespread use several years ago but is much
industry. Most forks now use either a coil spring or a chamber of compressed
less common now. Elastomers become brittle over time and lose their bounce,
air to give a fork its bounce, and a piston riding in a volume of oil to provide
and replacements are more and more difficult to find. In many cases, it's best
compression and rebound speed control. A polyurethane material commonly
to cut your losses and replace elastomer forks when this happens.
Here's how various rear-suspension designs address these
problems:
bob and biopacing. Some low-pivot bikes bear a striking
resemblance to the four-bar design described above. Here's
how to tell the difference: the key to the four-bar or FSR
linkage is the location of the rear pivots on the chainstay, just
ahead of the rear dropout. If the rear pivots are on the seatstays, above the dropouts, it's a low pivot, not a four bar.
Four-bar linkage. Also known as the Horst link (named for
its innovator, Horst Leitner) or as the FSR linkage (named so
by the patent's owner, Specialized bicycles), the four-bar
linkage produces a roughly vertical axle path that minimizes
bob and brake jack.
High-forward pivot. Many bicycle manufacturers use a
simple swingarm, pivoted above and ahead of the front
derailleur. A line drawn through the pivot and rear axle will
be roughly in line with the top of the middle chainring. This
pivot placement keeps the suspension active while pedalling
in the large or middle chainring, and it works to lock the suspension out while using the small chainring.
Low pivot. A single pivot point, located directly behind the
bottom bracket shell, allows the suspension to remain very
active at all times. As a result, this design is most susceptible to
Highly coupled linkage. Two very short 'coupling links' to
connect the main triangle to the rear triangle and a lot of
heavy calculations come together to make the highly coupled
linkage work. By carefully manipulating the length of each
link and the location of each pivot point, the travel path of
the rear axle can be tuned to make the suspension firm at the
beginning of the stroke (for efficiency while pedalling) and
more active as the suspension compresses further.
Floating drivetrain. A floating drivetrain design makes
strategic use of a chainstay length that grows slightly as the
swingarm compresses. The rear wheel is driven downward
while pedalling to aid in climbing on loose terrain. The
SUSPENSION
43
Rear Suspension At A Glance
FOUR-BAR LINKAGE
HIGH-FORWARD PIVOT
HIGH COUPLED LINKAGE
FLOATING DRIVETRAIN
LOW PIVOT
hese six designs represent the most utilized rear-suspension setups on the
there. Are you buying a full-suspension bike? Then you should pick the
market, though there are plenty of other less-common configurations out
design that best matches the way you ride.
floating drivetrain is unique in that it can be very active while
coasting — as you might be on a technical descent — and will
firm up while pedalling for efficient climbing or sprinting.
Soft tail. The soft tail is the simplest of rear suspension
designs. A short section of the seatstays is removed near the
seat cluster and replaced with a small shock. With only about
2 to 3 cm (1 inch) of travel at the rear wheel, lightweight soft
tails work with no pivots anywhere on the rear end. Instead,
the chainstays flex to provide the travel. At first, the idea
sounds questionable, but with such a small amount of deflection, the chainstays remain well within their safe limit to flex
and return without fatiguing.
Saddle Suspension
Sprung seatposts — as well as the Softride beam — eliminate
many of the maintenance issues that accompany swingarms,
linkages and oil-filled and pressurized shocks. By offering
extra comfort while seated and maintaining the efficiency and
simplicity of a rigid rear triangle, saddle suspensions are often
the first choice of both casual cyclists in need of a little extra
cushion while seated as well as many elite racers in search of
a lightweight alternative to full suspension.
Long Travel Bikes
Downhill (DH) and freeride bikes represent the outer limits
of bicycle suspension design. Here, on the wild fringe,
bicycles begin to look like motorcycles-sans-motor, as new
suspension designs are designed, developed and tested.
DH bikes are custom-built race machines that evolve
much more quickly than the publishing world can hope to
keep up with. Internal gearboxes, 30-plus cm (12-plus inches)
of wheel travel and disc brakes were all only experimental
`what-ifs' just a few short years ago. Now these technologies
are the norm at World Cup level and all but commonplace at
local amateur DH events all around the globe.
Freeride is a term that gets widely interpreted. In the early
days of the freeride movement, freeride bikes were essentially
long-travel cross-country bikes with short stems and riser
handlebars. 100 mm (4 inches) of wheel travel was pushing
44
ILLUSTRATED BICYCLE MAINTENANCE
the limits of what was reasonable for an all-around bike that
was a capable descender and a passable climber. These early
freeride rigs weighed in around 15 kg (32 pounds) or so. A
result of this was the birth of 'shuttling', where a group would
take turns driving a vanload of bikes and riders to the top of
a descent, eliminating all that pesky climbing on a pig of a
bike that didn't like going up all that well, anyway. Around this
same time, a small group of riders from the North Shore of
Vancouver, British Columbia, began testing just how steep
the fall line could get before freeriding became freefalling.
Darlings of the magazines, these North Shore riders legitimized a style of riding that had previously been viewed as
merely a failed suicide attempt. The terms North Shore and
freeride rapidly became synonymous. Manufacturers keen on
the trend began to push out bikes even more heavily built,
with longer travel, which became the freeride bikes we know
today. (It's interesting to note that those early North Shore
riders rode hard tail cross-country bikes fitted with 'long' [80mm (3-inch)] travel forks and riser handlebars. Many North
Shore and freeriders today still prefer the handling of a bike
with a rigid rear end.)
Yet what of up?
Early freeride purists have not been forgotten. Today's allmountain type bikes reflect the spirit of the first freeride
bikes. Thanks to leaps in technology, all-mountain riders
enjoy bikes with 10 to 15 cm (4 to 6 inches) of wheel travel
that weigh less than 14 kg (30 pounds) and benefit from
swingarm and shock designs that help the bikes descend and
climb equally well.
Suspension Adjustments
As we said before, if you own a suspension bike or added a
suspension component to your bike, you probably received a
manual explaining basic adjustment and maintenance
requirements. If not, contact the manufacturer and request
one. This is important — there are so many different types of
suspensions available that you must follow the manufacturer's
recommendations on setup and adjustments. If you don't have
a manual, you may be able to get advice from a shop
mechanic, provided your suspension is not too unusual.
The first adjustment to make is preload. This sets the suspension to your weight. For instance, if your air/oil rear shock
is low on pressure, you may bottom it out on bumps. And if
you're a light rider and the pressure is set too high, you won't
get enough action from the suspension to do you any good.
For air shocks, this is a fairly simple adjustment. First, use
the manual to determine what pressure is required for your
weight. Most air-sprung forks have a Schrader valve for pressurizing, but some require specific adapters or a needle, like
you might use for a basketball. Forks that require an adapter
usually come supplied with one. If your fork requires an
adapter and did not include one, or if the adapter has become
SPRING RATE PROGRESSIONS
AIR SPRING
RATE PROGRESSION
!
ti
COIL SPRING
RATE PROGRESSION
0
AMOUNT OF COMPRESSION
Air springs tend to get increasingly difficult to compress, especially near the
end of the spring's travel; coil springs compress at a much more linear rate
all the way through their travel.
lost or damaged, you'll need to pick up a new one from your
local shop. A custom-built suspension pump with a built-in
gauge works best for pressurizing air-filled forks. They can
push a very small volume of air to extremely high pressures,
making them both powerful and precise. Additionally, most
suspension pumps incorporate a bleed valve that allows you
to release pressure in small increments, which is tough to do
with a floor pump.
Rear air shocks usually require a lot of pressure — sometimes over 200 psi — so a proper suspension pump works best
for these. A floor pump may be substituted in a pinch, but it
may have a difficult time achieving the necessary pressure.
Once you adjust the preload on air shocks, it's important
to check them regularly. Because they contain small volumes
of air, the loss of only a few pounds can make the shock
operate poorly, so it's wise to check the pressure every week
if you're riding regularly.
Coil-spring suspensions are adjusted for rider weight by
turning knobs that compress the spring. But for coil-spring
systems preload is a fine-tuning adjustment only Applying too
much preload can make the shock bottom out. In time, it will
also overstress the coil and cause it to crack, so it's important
to begin with springs that are rated for the specific rider's
weight and work from there. Your fork's or rear shock's
owner's manual should provide guidelines detailing how
much preload is acceptable and what spring is the correct one
to start with for your weight.
Changing springs on rear shocks is relatively easy and
requires only a few basic hand tools. Changing the spring or
SUSPENSION
45
springs in your fork, however, is another matter. The tools TROUBLESHOOTING
required are still not very specialized, but the procedures vary
from manufacturer to manufacturer and can be a little tricky. PROBLEM: The fork or rear suspension doesn't feel like
As always when dealing with the unknown, read the manual it moves much over bumps.
first and start only after you understand the whole process.
Many elastomer suspensions can be adjusted for rider SOLUTION: The spring preload may be set too high.
Change the adjustment.
weight by preloading the elastomers inside, also. Some,
however, are tuned by changing the urethane bumpers. Manufacturers once offered bumpers in various densities, but as PROBLEM: Your suspension moves too much over bumps.
elastomers have fallen out of favour with most manufacturers,
it may be difficult to find new ones. If you have the necessary SOLUTION: Increase the spring preload until the suspension
bumpers, it's usually fairly easy to disassemble the suspension, sags very slightly when you're sitting on the bike.
remove them and replace them with softer or stiffer ones.
On some forks, changing the bumpers may require special PROBLEM: The fork doesn't move like it used to.
tools, such as superlong hex keys. Check your manual for
directions. Again, parts and tools were once readily available SOLUTION: Clean and lubricate the inner legs and bushings.
from suspension manufacturers. Now, it may take a little
PROBLEM: The fork doesn't move like it used to and
detective work to find what you need.
you
crashed.
Besides these basic preload adjustments, most suspensions
require regular maintenance to keep them functioning propSOLUTION: Have the alignment checked by a shop.You
erly. Check your front wheel quick-release regularly to ensure
that it's tight, because it's the key to keeping the two fork may have bent the fork legs.
legs moving as one. Every couple of rides wipe dirt from the
PROBLEM: Oil is leaking out of one leg.
legs (carefully lift up the boots if your fork has them), apply
light
fork
oil
and
compress
the
fork
a
few
times
to
work
a
the oil past the seals. This will help keep dirt out of the fork SOLUTION: You may have a bad or leaking seal in the
and lubricate the legs, keeping the fork action smooth and damping cartridge. Replace the cartridge.
friction-free. Once a month or so, put a wrench on the top
caps, brake posts and shaft bolts (on the bottom of the legs), PROBLEM: The top caps on the fork legs always loosen.
and gently snug them if they've loosened. And always keep an
SOLUTION: Replace the 0-rings on the caps (if there are
eve on the brake arch and dropouts for signs of damage.
If you race or ride hard, you'll want to clean and relube the any) and check the threads on the caps. Replace caps if
fork about every 2 months, or more often if you ride in wet they're damaged.
or muddy conditions. On some forks, this is easy. On others,
PROBLEM: After impact, the fork kicks back too quickly.
you ' ll want to take the bike to a shop. Also, many fork and
shock makers have service centres ready to quickly take care
SOLUTION: Stiffen the rebound damping.
of oil changes and rebuilds at a reasonable cost.
Elastomer shocks are usually simpler to maintain than
PROBLEM: On steep climbs, when you're standing and
models with air shocks and hydraulic damping. For forks,
keep the slider surfaces clean and lightly lubricated with a pedalling, you hear a rubbing noise.
spray or drip Teflon-based oil. On stems and rear shocks,
about the only upkeep you might have to do is to tighten the SOLUTION: The legs of the fork are moving independently,
pivot bolts if the parts develop play. And if you ride a lot, allowing the rim to brush the brake. Make sure the wheel is
you'll probably want to replace the elastomers yearly because centred in the fork and securely fasten the quick-release
skewer. Still rubbing? Upgrade the fork bridge or the hub.
they lose resiliency with enough riding.
All suspensions that rely on mechanical linkages may
loosen over time, so it's always wise to check the bolts occaPROBLEM: You hear knocking, clicking or creaking
sionally and tighten them if necessary. Rear swingarms are
sounds from the rear suspension.
particularly susceptible.You can push and pull laterally on the
rear wheel to feel for play; it shouldn't move much. If there's
SOLUTION: Put a wrench on all the pivot bolts to tighten
any clunking or looseness, the bolts securing the swingarm
loose ones. Check the manual to determine which pivots
probably need to be tightened.
require lubing and lubricate them.
46 ILLUSTRATED BICYCLE MAINTENANCE
Basic Suspension Adjustment
1
Suspension improves control and cushions the ride, but it's not maintenance-free. First, adjust it to accommodate your weight. On air shocks,
do this by adding or releasing pressure according to the settings that
the manual recommends for your weight.
Forks usually have two valves, one located on the top of each leg. To prevent
valves from being contaminated by dirt, they're sealed with either a screw
(for needle valves) or a regular plastic cap (for Schrader valves). Remove
needle-type caps with a Phillips screwdriver or Schrader caps by hand to
expose the valves. Now attach the pump. In a pinch, you can use a standard
bicycle pump, but it's best to use a special suspension pump. This usually
resembles a syringe with a gauge attached. It allows finer pressure adjustments, so it's easier to use, and the gauge is higher quality than on most
bicycle pumps, so it's more accurate. Place the pump on the valve and
operate the plunger to inflate each leg to the recommended pressure (see
photo). If you overdo it or if the fork already indicates too much pressure, let
some air out by depressing the bleed button in the side of the pump. When
2
you have the correct pressure in both legs, replace the screws or caps.
Rear air shocks require much more pressure than fronts, so exact
pressure is less critical. For accuracy, it's still best to use the pump supplied by the manufacturer.
But
if you're willing to estimate pressure,
you can do okay with a regular bicycle pump. The procedure is identical to
working on the fork, except there's only one valve and the pressure is much
greater. Remove the valve cap, install the pump and inflate the shock to the
recommended pressure (see photo).
Fine-tuning the ride of your coil-sprung fork or rear shock is as simple as
a twist of the wrist. To firm things up, turn the preload knob clockwise. To
soften, turn it anticlockwise. If the available preload adjustment isn't enough
to achieve the ride quality you want, you'll need to change the spring to one
recommended for your weight. Because the coil on a rear shock rides on the
outside of the shock body, changing it is pretty easy and usually doesn't
require any special tools. Changing springs in a fork is a bit more involved.
You will need to partially disassemble the fork to perform this job, so it's
advisable that you consult your fork's owner's manual before turning
so much as a single bolt.
SUSPENSION
3
47
Replacement parts for elastomer suspensions are rapidly disappearing. If you're lucky enough to have what you need, it's pretty
easy to adjust elastomer suspension to your weight by changing the
urethane bumpers. On forks, it is more difficult than adding air pressure; however, it's not so tough that you shouldn't attempt it if your fork doesn't have
enough travel or feels too stiff. It's usually necessary to disassemble the legs.
This may be as simple as unscrewing the top caps, or it may require special
tools such as long hex keys (see photo) - it helps to refer to the owner's
manual. For stems and rear shocks that employ elastomers, it's usually fairly
obvious how to disassemble the mechanism to change bumpers. And it generally requires only basic hand tools. To keep shock forks as friction-free as possible, once a week or so, lift the boots (if your fork has them), clean any dirt
from the legs, drip on a little lube containing Teflon and compress the fork to
work the lube past the seals. To ensure optimum steering precision, check the
front wheel quick-release. It has to be tight to tie the fork legs together. To
prevent problems due to loose parts, put a wrench on the top caps, brake
bosses and shaft bolts regularly.
4
The last type of shock maintenance that you can do yourself is
checking linkages. Since many suspensions rely on moving parts,
such as swingarms, that are bolted to the frame, it's important to
occasionally check them for play. Do this by wiggling the parts laterally.
If there's side-to-side play, the wheels won't track in line, which can lead to
squirrelly handling. You can prevent this by regularly checking the linkages
and tightening any bolts that have loosened (see photo).
Some shocks that rely on oil damping also require regular oil changes, but
this service is best performed by an authorized service centre. Some shop
mechanics can handle this, or you may have to send the shock back to the
manufacturer. If you must do the latter, the job usually isn't too expensive and
the manufacturer can generally turn it around quickly.
CHAPTER 4
Wheels and
Tyres
Most people know that the term 'bicycle' means 'two wheels'.
While the bike's frame may determine how the bike handles,
none of it would be possible without its wheels. A bike's ride
quality and some aspects of handling are heavily influenced
by the quality of wheels and tyres. A well-built wheel — tight
and true, with a properly inflated tyre — makes for an enjoyable ride every time. On the other hand, a loose, bent wheel
or a soft, underinflated tyre can make just a few minutes in
the saddle a miserable — or worse, dangerous — experience. A
bad wheel makes steering difficult, especially at high speeds,
and braking suffers similarly.
stopped spinning, of course) pluck at the spokes or squeeze
them in pairs to listen or feel for firm and equal tension. Bear
in mind that it is normal for the left-side spokes of a multispeed
rear wheel to have a lower tension than the right side. This is
known as a wheel's 'dish'. Any shop selling you a new bike or
wheelset should be willing and eager to touch up the true and
tension for you before leaving the store with your purchase.
A pair of wheels properly tensioned from the start will require
less attention in the future.
Exactly what you need. The ultimate
option is to have a pair of wheels cuminbuilt for you by an experienced wheelWhat Makes a Good Wheel?
Quality rims and hubs are both important, but
builder. Custom-built wheels are pricier
the keys to a wheel's strength are the spokes.
than a factory-built set, but what you get is
Even a mediocre hub and rim can become a
a wheelset built with your specific riding
great wheel when properly strung with
style in mind by a true craftsman who takes
quality spokes by an expert wheelbuilder. By
the greatest pride in his or her work.
carefully balancing tension all the way around
Learning to build your own wheels is
the wheel, a wheelbuilder creates a straight, Tyres are available in many sizes
another possibility. Wheel building requires
round and durable melding of art and science and tread patterns. From narrow, highpatience, attention to detail and a high level
— the bicycle wheel. Correct spoke tension
of skill. In fact, it may be too much for most
pressure tyres for maximum speed on
enables wheels to stay round and to withstand smooth roads to wide, heavily treaded
home mechanics to pick up, but the process
the pressures of weight and shocks transmitted tyres for the roughest trails (with many
should be well within reach of those with an
from the road or trail.
options in between), there is a tyre
above-average mechanical aptitude. It takes
When weight is applied to a wheel, the available to suit almost any terrain.
several wheels before you become truly prospokes beneath the hub lose some of their
ficient; in the end, though, the satisfaction
tension. If this tension is inadequate to begin with, the rim is and feeling of accomplishment gained from building and riding
in danger of becoming permanently deformed. A well-built
your own wheels is well worth all the effort.
and well-maintained wheel is thus a tight wheel, one in
which all the spokes are at optimum tension. Such a wheel
can better withstand pressures both from above and from the
side than a loose wheel can. A tight wheel flexes less than a
loose one, and so it experiences less metal fatigue. It's more
durable and less likely to go out of true, or round.
Luckily, chances are good that almost any wheelset you get
from your local bike shop, whether alone or as part of a new
bike, have been well built. It's still a smart idea to check them
before taking them home. Spin the wheels to check for true
(the straightness of the rim) and round. Then (after they've
The right rubber. Good tyres are constructed with a fabric
casing made of nylon fibres and may include the addition of
some exotic materials like aramid fibres (such as Kevlar) to
increase puncture resistance or reduce weight. Rubber compounds are selected to match the intended use of the tyre.
Racing tyres use thin, lightweight treads made of grippy
rubber; touring tyres use compounds developed to maximize
tread life; and mountain bike rubber is formulated to be
durable and maximize traction in a variety of conditions.
Cheap tyres are a false economy. They are most often made of
Where the Ruooer Meets The Roac
WHEELS AND TYRES
low-grade cotton or polyester fabric and low-quality rubber
that wears quickly. The biggest problem, though, with cheap
tyres like these is their low recommended inflation pressure
that makes for a mushy, vague ride.
A cushion of air. With correct inflation pressure, a tyre rolls
quickly and smoothly while at the same time conforms to
and grips the road or trail surface. A properly inflated tyre also
affords the rim protection from bumps, rocks and potholes. So
what is the correct inflation pressure? Every tyre has a recommended range printed on the sidewall. Generally
speaking, for road tyres you want to be right at the top of the
recommended range and for off-road tyres, you will want to
tailor the pressure to given conditions. On pavement or
smooth, fast, hard-packed trails like converted railroad beds,
traction is abundant, so you should pump your tyres right up
to their recommended maximum, often around 60 to 65 psi
to minimize rolling resistance. The usual range for off-road
riding is between 35 and 45 psi, but finding the right pressure
requires a bit of trial and error. For top performance, the correct pressure is as low as you can go without pinch-flatting or
folding the tyre over while cornering. Rocky trails require
higher pressure to avoid flats; lower pressures allow the tyre to
conform to the terrain, maximizing traction.
Variety. Tyres don't last; it's just the way things are. Take
advantage of this by experimenting with widths, tread
patterns, rubber compounds, etc. Work boots aren't right for
running a marathon, and casual shoes wouldn't be the best
choice for hiking. Similarly, bicycle tyres are specialized — and
only through trying lots of different tyres will you discover
what works best for your bike, your region and your riding
style. It's not at all unusual for an enthusiastic mountain biker
to have a closet full of tyres for different conditions or for
roadies to have heavy, long-wearing tyres for early-season
training and slender, lightweight ones for the racing season.
Selecting Wheels
Bicycle wheels come in an impressive array of sizes and types,
ranging from 12- to 29-inch diameters and 'X- to 3-inch
widths. The bicycle world contains several rim-and-tyre
numbering systems: the English-American and the European
standards are the most common. Although many wheels are
essentially interchangeable, the exact tyre-to-rim fit is unique
to each system.
The English-American standard uses two-digit numbers to
indicate the approximate wheel diameter (measured tread to
tread) in inches, followed by a tyre-width number. For
instance, 26 x 1.9 describes a wheel that, with its tyre, is about
26 inches in diameter and 1.9 inches wide.
The European system is metric, and wheel diameter is designated by a three-digit number, the approximate diameter in
51
millimetres. This number is sometimes accompanied by a
two-digit number, which indicates the tyre width. Usually
a letter (A, B or C) indicating rim width is placed after
one of these numbers. So, for example, the European counterpart to the English 26 x 1.9 might be labelled 650 x 48B or
simply 650B. The two tyres are similar in size but not
interchangeable.
Factors that must be considered when choosing wheels
include diameter (you'll most likely be dealing with a 26, 27
or 700C), rim width (this dimension affects tyre selection but
isn't formally numbered) and tyre size.
Wheel diameter. This is determined by the frame designer,
who proportions the fork and stays for a specific size. Most road
bicycles made for 27-inch wheels will not take 7000s. Some
will, but to be sure of the interchangeability, do a trial fit. Surprisingly, it's possible to fit 700C wheels in some mountain bike
frames to make the bike better for road use. When trying these
exchanges, always make certain that the brake pads reach the
rims (don't buy until you're sure they'll fit).
Rim width. This will affect your road-tyre choice. Although
there are no hard-and-fast rules on rim-tyre compatibility,
most rims will fit several road-tyre sizes. For instance, a narrow
rim with an outside width of 20 mm (often called a 1-inch
rim) will carry tyres with widths of 19 to 32 mm. When
making your rim selection, anticipate the full range of riding
conditions you think you will encounter. The table on page
52 shows which tyres are best suited for different types of
riding. Find the road tyres that you'll be using, then select a
compatible rim.
Tyre size. When selecting road and dirt tyres, beware that
although makers can be trusted to list diameters correctly,
their way of indicating width is undependable. One company's 25 mm tyre is the same size as another's 28. Some
26 x 1.75 labels would be labelled 26 x 1.5 by another maker.
So the exact size of a tyre can be determined only by
measuring the width of an inflated tyre. The International
Standards Organization (ISO) tyre size system, a five-digit
sequence, is potential salvation from this measurement confusion. Although tyre engineers understand and adhere to it, this
form of labelling is just starting to find its way to consumers
as a guide to tyre choice.
Besides size, tyres vary in many other ways, casing construction and tread pattern foremost among them. When choosing
tyres, keep in mind that the rougher the pavement, the coarser
the casing (which means larger and fewer cords, around 20 to 36
per inch) and the larger the tread pattern should be. Dry, loose
ground calls for numerous large knobs.Wet, muddy conditions,
on the other hand, are best met with shorter, more widely
spaced knobs that don't collect mud.
52
ILLUSTRATED BICYCLE MAINTENANCE
On smoother surfaces, such as well-maintained pavement,
casings can be made of finer, more numerous threads (from 36
to more than 100 per inch), and the tread patterns can be less
aggressive. On good roads, in the wet or dry, some of the best
results are obtained with entirely smooth tyres.
Compatibility of Wheels and Bike
When considering a change of wheels, you must not overlook wheel and bike compatibility. The factors affecting
compatibility are wheel diameter, rim width, hub axle size
and width and cassette type compatibility or, if you have an
older bike, freewheel threading.
Wheel diameter. The wheel diameter is important because it
must be compatible with the brakes. Brake pads must make
solid and secure contact with the sidewalls of the rim, which
serve as the braking surface. Because brakes are made in many
different lengths and are mounted to frames in different locations, don't assume your brakes will reach any size wheel. For
instance, bicycles equipped with 27-inch wheels will occasionally not accommodate the slightly smaller 700C size,
because the brake pads can't be lowered even Y1 inch. With
such small distances to measure, a trial fitting of the wheel you
hope to use becomes very helpful. Borrow a friend's or visit
a bike shop to see if the wheel you want to use will fit.
Rim width. This is a measure of wheel strength and indicates
the range of tyre options. Refer to the table below for
suggestions on tyre and rim sizes. Select a rim that is suited to
your type of riding.
Hub axle size and width. These must be appropriate for your
bike frame. Hub width is measured from locknut to locknut and
needs to conform to the space between the two blades of the
fork (see the illustration opposite) and between the two rear
dropouts on the frame. Otherwise, fitting your new wheel can
be a real thumb buster.
Most front hubs are 100 mm wide. Exceptions to this rule
include children's bikes, which have even narrower hubs, and
the rare tandem equipped with a front hub brake, which
requires a dished wheel and a hub of 110 to 115 mm width.
The same width consideration should be observed for the
rear wheel, where the range of sizes is wider. Road bikes
today run 130 mm wide and mountain bikes run 135 mm
with a few very rare exceptions, but older bikes may be 120,
125, 126, 127 and 130 mm (for older mountain bikes) wide.
Try to achieve a close fit so the difference between wheel and
frame is no more than 3 mm.
The goal of racing teams is to set up all their bikes with
the exact same spacing for all rear wheels and frames. If all
derailleurs are set up for the same cassette cog space, then
lightning-fast wheel changes are possible. Whenever you
expect to regularly use several different rear wheels on your
bicycle, take the time to make each overall width and cassette
spacing the same. Damaging chain overshifts from misadjusted
derailleurs can occur after wheel swaps, but they're avoidable.
Axle diameter varies according to the axle type. Quick1
mm than most nutted axles.
release axles are thicker by /2
Many bicycle frames can handle either type, but some
designed for nutted hubs have dropout slots that are too
narrow to permit the thicker quick-release axle. Since the
convenience and popularity of the quick-release system is so
overwhelming, consider filing your dropouts to enlarge the
slot openings. The amount of metal to remove is small; work
very carefully and don't misshape the dropout and cause the
wheel to sit crooked.
RIM AND TYRE COMPATIBILITIES AND USES
Rim Category or Name
Rim Width (mm)
Rim Weight (g)
Tyre Sizes
Typical Uses
Road clincher
19-21
395-500
700c x 19-32mm and
27" x 7/8 –1X"
Road racing and
sport/light touring
Touring/hybrid/29"
clincher
22-28
500-600
700c x 28-47mm,
29" x 2.0", and
27" x 11/8 - 1 Ys"
All-purpose touring,
tandem, casual riding,
and 29" mountain bike
racing
Mountain bike clincher
25-32
500-1100
26" x 1.25-3.0"
Mountain bike racing,
general off-road riding,
casual riding, off-road
and third-world touring
Tubular
1 9-21
300-420
700c x 18-32mm
Road, track, and
cyclocross racing
WHEELS AND TYRES
53
Downhill and freeride mountain bikes with long travel
forks often come equipped with a very large-diameter axle
called a through-axle that helps resist unequal compression of
the fork legs. (We'll touch on this design further in Chapter
5.) Chances are that if you have one of these, you will already
be aware of it.
Be aware that the quick-release axle must protrude past the
locknut so the dropouts can rest on it — but the amount that
protrudes past the locknut must not be longer than the
dropout is wide. On inexpensive bicycles fitted with higherclass hubs, this is often the case. If so, the clamping skewer
won't secure the hub when tightened and the wheel can pull
out when you pedal.The solution is to file the end of the axle
until it's the correct length to allow the quick-release to
clamp the frame.
Cassette-type compatibility. A big issue any time you're
swapping rear wheels is gearing compatibility. Two types of
mechanisms are in common use for holding gears (cogs) on
the rear wheel.The standard today is cassette cogs, which slide
onto a splined body built into the hub called a freehub. The
freehub contains bearings for coasting and a ratchet mechanism for driving the bike, hence the clicking sound when
you're coasting.
The advantage of cassettes is that because the freehub is
part of the hub, the main hub bearings are placed further
apart, which reinforces the all-important hub axle and prevents breakage (formerly a common problem). Also, the cogs
are held in place by a lockring, which is relatively easy to
remove for simple cog replacement.
Naturally, the two big component manufacturers couldn't
agree on a standard spline that the cassette cogs slide onto, so
now we have two standards, the Shimano and Campagnolo
spline patterns, which are not interchangeable. When pur- Hub width is measured from the outer edges of the two axle locknuts.
chasing wheels or planning upgrades, be sure to get a wheel This distance should be equivalent to the space between the dropouts
that matches the cassette you're planning to use.
of the frame or fork.
The other problem is the number of gears on the cassette.
It's best if this matches also (though for upgrades there are
Because freewheels are threaded onto the hub, a special
spacer kits that allow you to add a cog). Standards keep removal tool is required to unscrew the freewheel from the
changing as competitors and engineers up the ante on hub. And because the cogs and bearing/driving mechanism
what's best for serious riders. The important thing to know are combined, it can be more difficult to remove the cogs than
is what you're trying to match when you're doing repairs
on cassette systems. Special tools may be required (depending
or replacements.
on the type of freewheel).
If you have an older bike or if you purchased a bike at a
In any case, when upgrading wheels, it's the perfect time to
department store, it's also possible that you have a freewheel upgrade to a cassette system. This is best because freewheels
instead of a cassette on your rear wheel. Freewheels preceded are getting hard to find. Even if you find one, you may be
cassettes and are different to work with. The basic difference out of luck later on when you need parts for it. If you have a
is that a freewheel contains the cogs and the bearing and
cassette system, on the other hand, it'll be easy to find the
drive mechanism in one unit that is threaded onto the rear parts you need.
hub (remember that on cassette systems, the bearing and drive
If you must go with a freewheel, make sure that the
mechanism is built into the freehub, which is part of the hub,
threading matches that on your hub. The standard is English,
and the cogs are separate).
and that's what's found on all mountain bikes and most road
54
ILLUSTRATED BICYCLE MAINTENANCE
bikes made after 1980 or so.The only bike that might give you
trouble is an older (1960s or early 1970s) French road bike,
such as a Peugeot or Gitane. On these, it's possible, even likely,
that the freewheel is French-threaded. Don't try to screw on
an English-threaded freewheel in this case. It's slightly larger
and it'll seem to go on, but the first time you go for a ride,
it'll strip the hub threads. Consequently, if you have this type
of bike and want to upgrade, the best bet is to get a cassette
wheel or at least a used wheel that's threaded to accept an
English freewheel threading, because some English freewheels
are still available.
Special-Use Wheels
Speciality bicycles often use very different equipment than
day-to-day machines. Track bicycles don't use brakes and
punctures are rare on the velodrome surface. This explains
why lightweight glued-on sew-up tyres (also known as tubulars) are so universal for track racing. For explosive events like
matched sprinting, which features unpredictable manoeuvreing and sudden acceleration, 32- and 36-spoke wheels
with sturdy rims in the 350-gram range abound. But for individual pursuit, in which speed is steady and riders have the
track mostly to themselves, rims can weigh as little as 260
grams and have 24 or fewer spokes.
Mass-start road racing is a rough-and-tumble world governed by weather and pavement conditions. Potholes, crashes
and punctures are facts of life, so the most popularly used rims
are 'team weight': that is, from 395 to 420 grams supported by
32 or 36 spokes of full 14 (2.0 mm) gauge. In certain circumstances, such as lighter-weight riders and on better roads, as
few as 28 spokes are used and rims can be as light as 340 grams.
Composite aero wheels are also becoming common due to the
wind-cheating effect they offer.
Triathlon racing has room for all equipment. Since it's a
timed, largely individual race usually over good roads, many
competitors employ the lightest possible wheels and tyres.
However the emphasis is on steady speed and not acceleration, so rim and tyre weight are not terribly important. Many
smaller triathlons are won with everyday clincher rims and
tyres, in good condition and inflated from 100 to 155 psi.
Some of the best bicycle touring these days is on infrequently traveled rural roads. These roads are safer due to low
traffic, but they're poorly maintained. To ride a bike carrying
loaded panniers, wheels must be sturdy and tyres generous.
Use 27-inch and 700C rims of 500-gram weights capable of
handling larger tyres, or 26-inch rims in the 450-gram range.
The same formula applies to tandem bikes, which also benefit from an increased number of spokes in the wheels.Where
most bikes have 32 spokes per wheel, tandems sometimes
have as many as 48.
Freeride and downhill mountain bikers use special wheels
that are designed to be almost indestructible, with heavy rims,
tyres, hubs and spokes. When disc brakes are used on the
bikes, the wheels often have special rims without braking surfaces. Unlike cross-country wheels, weight is a secondary
consideration for downhill racing, where races are won and
lost in tenths or even hundredths of a second, so reliability is
paramount.This is even more so in freeriding, where anything
less than ultimate durability could result in serious injury.
Wheel Systems
A hot trend in the last several years has been the wheel
system. Sometimes referred to as `aero wheels' or low-spokecount wheels', wheel systems are complete wheels from the
manufacturer designed as a single unit that includes rim,
spokes and hub, to balance weight and strength. They look
very unique and high-tech, too. By building wheel systems in
large quantities with specially trained assemblers, manufacturers are able to produce high-performance wheels that
compare favourably in price to the high-quality, hand-built
wheels you might get from an experienced wheelbuilder. On
the surface, it might seem as though wheel systems could put
traditional wheelbuilders on the endangered species list. This
isn't quite the case. With all that wheel systems have going for
them, traditional hand-built wheels still hold a very important
trump card: consistency. All manufacturers of wheel systems
wish to create one-of-a-kind brand images for themselves,
resulting in a fiercely competitive market where innovations
are not shared. So Shimano's wheel system hub won't work
with Campagnolo's wheel system rim, and neither one's
spoke is interchangeable with Spinergy's, and so on. Conversely, if you buy a well-built traditional 32-spoke wheel in
London and break a spoke in Munich or need an axle in Marseilles, chances are you'll be rolling again in no time. So, for
ultimate performance, wheel systems could be the way to go;
but for a balance of performance and serviceability, traditional
wheels still come out on top.
Wheel Maintenance and Repair
The best way to obtain outstanding wheel performance is to
make sure that the wheels are appropriately designed for your
riding, constructed from top-quality components and
expertly built. From then on, avoiding damage is the biggest
challenge. Unless they become damaged, well-built wheels
don't need periodic maintenance apart from hub lubrication.
Moreover, quality tyres will last for many thousands of miles
if kept properly inflated and free of glass, metal, wire and
other debris. Unfortunately, many wheels are not expertly
designed or built. Such wheels demand more time and effort
for maintenance and need to be repaired more frequently.
These routine maintenance tasks will help you avoid repairs.
Maintain proper spoke tension. Wheels built too loose, as
the mass-produced ones can be (more of a problem on road
WHEELS AND TYRES
than mountain bike wheels), can loosen even further with
use. Wheels plagued by many limp spokes are dangerous and
deteriorate rapidly. On road wheels, this can lead to sudden
collapse or spoke breakage, because every time a wheel is used
the spokes accumulate fatigue. Tight spokes last much longer
than loose ones, though they all eventually wear out.
Spoke wear occurs when spokes are loose and can move
inside the hub, flexing slightly as you ride. Then, similar to
what happens when you flex a piece of wire back and forth
repeatedly, the spoke eventually fatigues and breaks.Tightness
enables each spoke in the wheel to remain fixed and avoid the
flex that leads to breakage problems. A tight wheel is also able
to resist severe loads more successfully than a loose wheel.
Besides much longer life, a tight wheel is less likely to have
individual nipples rattle loose from vibration. If you find one
loose spoke and the rim isn't dented at the spot, the culprit is
a wheel that's simply too loose. The remedy for the problem
is to lubricate all the nipples, tighten the loose one and then
add tension all around, perhaps one-half turn to each. Go easy
on the general tightening — as spokes reach their optimum
level of tension, small twists of the nipple add tension very
rapidly. Occasionally, nipples need to be glued tight (with
thread adhesive), but adequate overall tension normally keeps
a wheel free from further loosening.
Be aware that excessive tension can create instability and
make a wheel susceptible to sudden collapse.To be on the safe
side, find a well-built wheel that you can use as a model.
When plucked, similar-gauge spokes will make a musical note
that is proportional to tension. Higher is tighter, lower is
looser. Make your wheel approximately as tight as the one
you're using as a model, but no tighter.Your aim isn't to make
the wheel as tight as possible, just tight enough to prevent any
spokes from loosening during use. It takes a good bit of experience to be able to sense when a wheel has reached this
optimum level of tightness, so don't expect to automatically
get it right the first time you try.
Properly inflate tyres. Air-filled, pneumatic tyres were one of
c-vcling's great breakthroughs. They provide traction, comfort
and protection for the rim. To deliver these advantages, tyres
need to be properly inflated. The number-one reason that
wheels are rebuilt is rim damage, and the number-one cause
of rim damage is underinflated tyres, especially on road bikes,
which have much less air volume than mountain bike tyres.
Yes, owner laziness or inattention to proper tyre pressure is an
even greater threat to tyres than ruts, roots, potholes, curbs and
other hazards.
Before every ride, check the tyre pressure on your road
bike and inspect the tread for cuts. Setting off with underinflated tyres is a terrible financial risk if you're riding on
expensive wheels. With no warning, a minor road hazard
could lead to a major repair bill.
55
Because mountain bike tyres hold so much more air than
road models, inflation is less critical. Still, check pressure
regularly because even with fat tyres, low pressure can cause
problems. Besides rim damage, the other big cost exacted by
underinflated mountain bike tyres is tube pinching.When the
tyre is collapsed by a rock or curb, the tube is caught between
it and the rim, and the rim often cuts the tube.You'll recognize
a puncture caused by pinching by the telltale pair of 'snake
bite' holes that it typically produces.
Bypass road hazards and rim damage. Even when your
wheels are appropriately tight and your tyres are properly
inflated, you can still easily ruin a rim. Hitting a deep pothole,
wiping out on a rut that catches and twists your wheel,
or ramming something hard enough are just a few rimdamaging possibilities. Prevention is the key. On a road bike,
it's important to avoid hazards as much as possible. If you can't
avoid a hazard a good way to soften the blow and save your
wheels is to get off the saddle when you spot bumps ahead.
Bend your knees and arms like a jockey riding a horse and let
the bike float over the rough stuff.
Obviously, you won't avoid every hazard off road (what
fun would that be?).The key for keeping the wheels safe here
is proper tyre pressure. It's amazing what a good pair of
mountain bike wheels can handle if you maintain the correct
tyre pressure.
Despite all your precautions, you may find that your
wheels receive occasional dents. If this is the case, try one of
the following solutions:
Pump it up. Increase air pressure to the maximum after
first inspecting for any tread or sidewall cuts.
Go to larger tyres. Many riders can't use the very
smallest tyres without experiencing costly rim injuries.
Tiny road tyres are the best option for smaller riders or
near-perfect surfaces.
Punctures, headwinds and dirty chains are facts of life.
Wheel damage need not be. If there are no crashes, underinflated tyres and avoidable hazards, an appropriately designed
and well-built wheel should deliver many years of troublefree service.
Avoid spoke damage. Spokes are usually damaged in two
ways. Something gets caught in them, or you shift into low
gear (your easiest gear) and the chain overshifts and lands on
the spokes, cutting them. (The most likely cause of overshifting is a bent derailleur.) Common sense can minimize
the chances of either problem. However, if you discover that
one of your wheels is inexplicably out of true, check for bent
spokes or chewed up spokes.
56
ILLUSTRATED BICYCLE MAINTENANCE
Test the gear before you reach a steep section. One thing
to remember when riding any bike is to always ease off your
pedalling effort when shifting onto the largest cog (your
lowest gear). That way, if the derailleur is bent and the chain
jumps over the top cog into the spokes, you'll be able to stop
pedalling immediately, before any real damage is done. This is
especially important after a wheel change or when riding a
bike with improperly adjusted derailleurs.
When adjusting the derailleur, don't allow it to move
closer to the spokes than necessary. It's better to just barely get
into low gear than to occasionally throw your chain into the
spokes because once drive-side spokes get scratched, they are
much more likely to break.
After crashing, dropping your bike on its side or jamming
your bike into a car with its right side down, shift gently
through the gears to ensure that the rear derailleur has not
been bent. If it has, shifting into low gear may cause spoke
damage — and if you're really unlucky, the wheel might grab
the derailleur, pulling it into the spokes and ruining the
derailleur, too.
Removing and Remounting Wheels
You have to master this operation because without it you won't
be able to repair flat tyres, the most common bicycle breakdown. It's also essential for putting your bike on certain car racks
or disassembling it to store it in a small place. The key to easy
wheel removal and installation is proper fit.Whether your wheel
is fastened to the frame with nuts or a quick-release, the removal
and remounting procedure should be as easy for you as putting
on or taking off your shoes.
Open the brakes. Because brake pads are usually adjusted so
that they are close to the wheel rims, the first step in wheel
removal is finding a way to spread the brakes. Forget this step
and the tyre will jam in the brake, making it hard to get the
wheel off and on. It's true that you can take off a wheel with a
totally flat tyre without opening the brake, but you'll have to
open it when the tyre is fixed and inflated, or it won't fit through.
Fortunately, most bikes equipped with quick-release hubs
also have quick-release built into the brakes for slackening the
brake cable, which allows the calipers to spread enough for
tyre removal.
Most road bikes have sidepull brakes. To open these, look
for small levers on the brake caliper (the U-shaped part over
the wheels), near where the cable is clamped. For recent
Campagnolo brakes, look for a button on the brake lever.
Open the levers or push the buttons to spread the brakes and
get the wheels off easily.
Cantilever brakes, which are what you'll find on many
mountain bikes, are opened by releasing the transverse cable
(the wire that runs from one side of the brake to the other).
Squeeze the brake pads to the rim with one hand to create
slack, and lift one end of the transverse cable out of its pocket.
Let go of the pads, and the brake will spring open.
On direct-pull cantilevers such as Shimano V-Brakes,
squeeze the pads to the rim, then pull back on the L-shaped
`noodle' and lift to release it and the cable from the stop.
Disc brakes don't require any sort of release mechanism
to ease removal and installation of your wheels. Take care,
however when installing wheels to not force the disc into the
caliper. If you find that the disc does not slip easily into the
caliper, a brake pad may be out of place. Forcing the disc at
this point could cause severe damage to a piston or to the disc
itself. Also be careful to not squeeze the brake lever of selfadjusting hydraulic disc brake models when the wheel is
removed. This can cause the caliper pistons to fully distend,
locking up the system.
Get the wheels off. The next step for derailleur-equipped
bikes is to shift onto the smallest outside cassette cog (on the
back).This puts the chain and the derailleur in a position with
enough slack to ease wheel removal.
Front wheels are the simplest to remove. First, loosen the
axle. If it's held with nuts, use a spanner to loosen one side a
bit, then the other, and back to the first. Nuts should be tightened or loosened gradually. If you try to loosen one side all at
once, you might loosen or tighten the hub-bearing adjustment, which can cause bearing problems.
Open quick-release levers by pulling the lever away from
the frame until it points straight out and then rotate it around
until it's parallel with the frame again. In some cases, this 180degree rotation will, like loosening the nuts, allow the hub to
come free from the front forks.
Deal with wheel retention devices. Most modern bikes have
forks with wheel retention devices built into the dropouts.
Usually, these are ridges that prevent the wheel from falling
off even if the quick-release is mistakenly left loose. While
these are a nice safeguard, they make it a little trickier to use
the quick-release because when you swing the lever 180
degrees, the release doesn't open far enough to clear the stops
on the fork. To remove the wheel, hold one end of the quickrelease after swinging it open and unscrew the other end
enough to get the wheel off.
Loosen the axle nuts gradually, or the quick-release all at
once. Check to see that the brakes are widened to permit tyre
clearance. Now give the wheel a sharp blow from behind. If
it's ready to be removed, this blow will jar the axle in the
dropout slots, hopefully freeing it.
Free the rear wheel from the chain. Once the axle is out of
the dropouts, the wheel is free. With derailleur bikes, it helps
to grab the rear derailleur and twist it back (clockwise) so the
WHEELS AND TYRES
wheel can exit. Now the only encumbrance is the chain, and
it must be unlooped from the wheel. Lift it off by hand if you
don't mind getting dirty. Or learn to jiggle it off by shaking
the wheel, which will keep your hands clean.
Make sure it fits right. Most of the difficulties encountered
when replacing wheels are caused by a mismatch between
frame and wheel. It's worthwhile to let an expert adjust your
frame with alignment tools if necessary to allow your wheels
to fit properly.
Tyre Mounting and Tube Repairs
Tyre removal is a deceptively easy task, well within the abilities of anyone who can ride. Because punctures are largely
unpreventable, it's vital that every cyclist learn how to remove
a tyre, repair the tube and replace both. It's considerably easier
to remove and install mountain bike tyres than road tyres. But
with both, success depends on four factors, the last and most
important of which is correct procedure.
1. Rim and tyre size. These must, of course, match.A difficult fit is rarely caused by mismade rims and tyres. Rim
makers almost never err by more than 1 percent in diameter. Major tyre companies are scrupulously careful to
match their tyres to prevailing rim designs. The most
likely mistake you'll make is to try to use a too-narrow
tyre. Although its diameter might be correct, the tyre's
inadequate width will make installation difficult (unless
you replace your tube with a supernarrow model). And
the narrow tyre may be susceptible to pinch-flats and may
allow rim damage because its profile isn't tall enough.
2. Rim design. Some rims are easier to put tyres on than
others. There's no easy way to second-guess how a tyre
will fit, though. The biggest factors seem to be overall
diameter and the difference between the rim's inner
trough and its upper edge. When you install a tyre, the
mounted bead sits in the centre trough of the rim, while
the remainder is lifted over the rim edge.The difference
between these two provides the slack needed for installation and removal. The larger the difference, the easier
the fit. To get the most benefit from this slack, use the
thinnest rim tape possible. Almost all rims require rim
tape or liner to protect the tube from the ends of the
spoke nipples. (The only exceptions are a few one-piece
composite aero wheels that don't use conventional
spokes.) The thinner the material used for this liner,
however, the simpler it is to mount tyres.
3. Tube size. Whenever possible, use a tube that is one size
smaller than the tyre. For instance, use a 1-inch tube
with a 1 X -inch tyre and a 1Z, -inch tube in a 2-inch
57
mountain bike tyre. The more compact the tube, the
si mpler it is to insert and the less crowding will occur as
the tyre's last tight section is lifted onto the rim.
4. Procedure. The last critical factor is procedure. Without
skillful procedure, even the best-matched components
refuse to cooperate. As with any endeavor, attitude plays a
crucial role. Tyre mounting catches us at bad moments,
especially after unwelcome flats. The embarrassment of
delaying a group ride or the disappointment of being late
to work is enough to make most people cross-eyed with
impatience. Work smoothly and efficiently and you'll
soon be rolling again. For complete step-by-step instructions for tyre and wheel mounting and tube repairs, see
the sections at the end of this chapter.
Removing the tyre. After the wheel is removed, ensure that
the tube is completely flat. Unscrew and depress the tip of a
presta valve or poke the tyre lever into a Schrader valve and
squeeze the tyre to push all the air out of the tube. Once the
tube is deflated, press the beads of the tyre together and away
from the rim edge, down into the centre trough, as shown in
the illustration on page 59. That's how you get some slack to
lift one section of tyre over the rim edge with tyre levers. Use
one lever to pry the bead over the edge of the rim and then
hook its end onto a spoke. Then place another lever a few
inches away on the same side of the tyre and pry the bead off.
Repeat with a third lever and slide it around to pop off that
side of the tyre. Now reach in and pull out the tube.To remove
the valve stem, the loose bead must be lifted over the valve
hole. Leave the other half of the tyre on the rim.
Finding and marking the hole. Inflate the tube. With luck,
you'll hear a hissing sound. If so, mark the spot. Either make
index marks above and next to the hole but 10 nun (X inch)
away or so (because the glue will hide the ink if it's directly on
the hole); or if you don't have a pen, tear the hole to about
5 mm (X inch) to mark it (don't worry, the patch will still work
perfectly).
If you don't hear hissing, it's either a slow or fast leak. The
latter is easy to find because there's usually a large hole in the
tube — you'll see it if you look a bit. Slow leaks can be tough.
The best test is to submerge the tube in water and look for telltale bubbles.Take your time because a small hole will release air
;lowly. Linger on each section for a few seconds as you inspect,
and mark the hole immediately so you don't lose it again. Still
:an't find a hole% If it's a Schrader valve tube, it may be a valve
Leak. Put a little spit or water on the valve and watch for a few
seconds to see if a bubble forms. If so, use a valve tool to tighten
:he valve and test it again. Still leaking? Remove the valve core,
g
ut a drop of oil on the rubber piece on the core and reinstall.
Dr replace the core.
58
ILLUSTRATED BICYCLE MAINTENANCE
Patching the tube. Start by scuffing the area around the
hole with the sandpaper or metal scraper included in the
patch kit. Scuff an area a little larger than the patch you
plan to use. After scuffing, brush away the rubber dust with
your hand.
There's a type of `glueless' patch designed for quick repairs
that simply sticks to the tube. Park Tools makes one. With it,
once the tube has been scuffed, just peel off the backing, stick
the patch over the hole and reinstall the tube. These patches
are designed to be temporary, but they'll get you home and
they require less effort than a proper patch job because no
gluing is required.
If you prefer to permanently repair the tube, use a normal
patch kit. Such kits contain patches, glue, a piece of sandpaper
and instructions. The patches are so effective that it's possible
to patch a tube many times with no bad effects.
Apply plenty of cement to the tube. The glue should be
thin and runny. If the solution is thick and gummy, it will
barely work. Smear the cement over a generous area, larger
than the patch you plan to use. Once the shiny, wet surface of
the cement dulls, it's ready. On a dry day, it usually takes about
5 minutes for the glue to dry completely. Wait longer if
needed. Don't apply the patch until the glue is completely dry
or it won't stick.
Applying the patch. Most patches come with a protective top
layer of cellophane and a bottom layer of foil. Hold the cellophane and pull slowly to separate the patch from the foil (discard the foil piece). This exposes the sticky side of the patch.
Don't touch this surface because you'll contaminate the glue.
Place the patch onto the tube (make sure you cover the hole)
and press firmly so it bonds to the tube. Leave the cellophane
in place because it'll help keep the glue from sticking to the
inside of the tyre.
Before you reinstall the tube (an efficient time to do this is
while the glue is drying), check the condition of the tyre by
running your fingers — or a rag, which is safer — around the
inside. Remove any bits of wire, thorns or glass before
inserting the repaired tube, or else you'll probably have
another puncture right away.
Installing the tube and tyre. Before installing the tube,
inflate it just enough to round it out and remove wrinkles.
This little bit of air is the key to avoiding getting the tube
stuck under the tyre bead, a glitch that will complicate tyre
installation.
First, fit the tube's valve by lifting the tyre bead back and
away, exposing the valve hole. (If you had to remove the tyre
completely, start installation by putting one side of the tyre on
the rim.) Get the valve in place, then work the rest of the tube
into the tyre. After it's inside the tyre all the way around, go
mound Agana, \NoTking, the tube up and onto the rnn.Whcn
done, the free tyre bead should be flat against the rim and the
tube should be completely tucked up inside the tyre and onto
the rim.
Now is a good time to double-check whether you have the
tyre on right. Some mountain-bike tyres are directional,
meaning the tread should face a certain way. Look for arrows
on the tyre sidewalls that show which way to install the tread
for top performance. An extra little trick that may seem
insignificant but can save time in the future is to always install
your tyre with the label adjacent to the valve stem.When you
get your next flat (and it will happen, trust us), you can quickly
and accurately locate an offending object in your tyre by
matching the distance from the valve stem to the puncture
from the label on your tyre. Now you've got two spots to
check, rather than the entire circumference of the tyre.
It's best to reinstall the tyre by hand because tyre levers can
pinch and cut the tube, repuncturing it. Begin remounting
the bead at the valve stem. Once both beads are in place on
either side of it, push the valve stem up into the tyre to ensure
the tube is not caught under either bead. Hold the wheel on
your lap and work your hands away from each other around
the wheel, popping the tyre bead on to the rim by pushing
down with your thumbs or the heels of your hands (with
your fingers resting on the back side of the rim). When you
get to the last section, opposite the valve stem, it gets tough.
Don't give up.
Crouch and put the section of the wheel you're working
on on top of your right knee if you're right-handed, or on
your left knee if you're left-handed. Hold the tyre bead on the
rim on one side with your weak hand so it can't come
undone as you work on the other end of that last tough section of tyre. Using your stronger hand, work about an inch of
the section onto the rim. Pop it on by pushing down and forwards with the heel of your hand (now that you're pushing
against your knee you have plenty of leverage).When you get
an inch on, push another inch on, and so on. When the last
bit pops into place, you're finished. Good job.
Seating the tyre on the rim. With the tyre replaced on the
rim, take a breather. Start inspecting the bead seat by pushing
the tyre away from the rim, one side at a time, and looking
down into the rim. Make sure the tube isn't visible. If the tube
is caught under the bead, the tyre isn't seated on the rim correctly, and it won't inflate evenly and may blow later. Wiggle
the tyre to work the tube under it, or gently poke the tube
inside the tyre with a tyre lever (be careful, or you'll cut it).
One last time, push the valve stem up into the tyre and pull it
back down, snugly.
Inflating the tyre. If everything looks right, add 20 to 30
pounds of pressure. If you're using the pump on your bike,
attach n to the, valve carefully. Schrader valves me nearly
WHEELS AND TYRES
59
-ow to Remove a Clincher Tyre
1. Squeeze the deflated tyre to push
the tyre bead off the bead seat
2. Slip a tyre lever under the
unseated bead.
and into the trough of the rim.
bulletproof, but metal presta valves can break if you're rough.
To prevent too much pressure on the valve while pumping,
hook a thumb over the tyre and put your fingers behind a
spoke and around the pump head on the valve.This technique
will ensure you never break a valve while pumping.
When it's inflated a bit, rotate the wheel to see that the tyre
is sitting uniformly. Bulges at low pressure can be explosive at
high pressure. If the tyre looks straight, inflate to full pressure.
If not, lubricate the beads with soapy water and reinflate, or
simply dismount everything and try again.
Tubeless (UST) Tyres
Nlanv mountain bikes now benefit from a tyre-and-rim combination that eliminates the need for an inner tube. This
system, called Nagesti or Universal System for Tubeless
(UST), relies on a rim with a special internal shape and a tyre
with a butyl rubber liner moulded right into the casing. UST
can save a marginal amount of weight (there is no inner tube,
but the liner in the tyre makes it slightly heavier than a similar non-UST model) and reduces the risk of pinch-flats.The
real magic of the tubeless system, though, is traction. By running about 10 percent lower air pressure than you normally
would, a UST tyre's tread can spread out wider, yielding a
larger contact patch on the trail. With a typical tube-type tyre,
inflation pressure must be kept higher to minimize the risk of
pinch-flatting and to reduce rolling resistance caused by friction between tube and tyre as the tyre tries to deflect and
adapt to changes in the terrain. Here are the steps for
changing UST tyres.
r
Remove the tyre. Once deflated, pinch the tyre's sidewalls
ards one another until you feel and hear one of the beads
c out of its channel. This may take some force.
3. Pry the bead up and over the
side of the rim.
4. Gently slide the lever along the
unseated bead to remove the tyre
from the rim.
Get a grip. If pinching isn't enough, grip the tyre firmly from
the top with your strong hand and the rim from beneath with
your weak hand. Pull with your weak hand and push the tyre
with the heel of your strong hand. Few tyres should be able to
resist this technique. Determine which side has come free and
continue pushing this bead out of its channel all the way around
the tyre.
Tuck the head into the centre of the rim, where the rim's
diameter is smallest. You should then be able to carefully pry
the first tyre bead over the rim wall by hand. Tyre levers can
rupture the airtight lining of the tyre or scratch the sealing
surface of the rim, so it's best to avoid their use entirely. Some
tyres, of course, will defy even the strongest of fingers. Reach
for a lever only as a last resort.
Good things come in threes. For those exceptionally tight
tyres, get three of the widest, flattest plastic tyre levers you can
find. Pry the tyre with a lever and use the lever's hook to hold
it in place on a spoke. Repeat this with a second tyre lever,
and then a third. Remove the middle tyre lever and 'leapfrog'
past the third, repeating this step until the tyre bead is sufficiently loose to release the rest of the bead by hand. Pop the
second bead free of its channel in the same manner you did
the first. Once out of its channel, the second head should
come off the rim with relative ease.
Flat repair. Patching a UST tyre is done in much the same
way that you would patch an inner tube, but the patch is
installed on the inside of the tyre, not the outside. First determine the nature of the leak. A simple puncture from a thorn,
shard of glass, nail, etc., can be patched using a vulcanizing
glue patch like those used for patching inner tubes or with
a tubeless-specific patch such as the one manufactured by
60 ILLUSTRATED BICYCLE MAINTENANCE
Hutchinson. Most tubeless tyre manufacturers recommend
against glueless patches.
SCHRADER VALVE
PRESTA VALVE
Cleanliness is next to airtightness. Locate and remove the
cause of the puncture from the outside of the tyre. While
you're at it, check the whole tyre for other debris that could
cause trouble further down the trail. On the inside of the tyre,
clean the area around the puncture, ensuring that it is free of
debris.
Go ahead, be rough. Using a coarse piece of sandpaper or
other abrasive material, deeply scuff the butyl liner in the area
surrounding the hole slightly larger than the patch you will
use. Apply a dot of glue and spread it around the abraded area.
The Schrader valve (left) is similar to valves found on automobile tyres,
whereas the presta valve (right) is thinner and has a small nut that must be
loosened prior to tyre inflation. The core of a Schrader valve can be removed
Be patient. Let the glue set up for several minutes — and don't
let one of your know-it-all buddies convince you to burn off
the evaporating fumes to speed the process! When the glue
has gone from clear to cloudy, it's ready for the patch.
Stick it. Peel the foil backing from the patch, exposing the
coloured side (usually orange), press it firmly into the glue
and hold it there for at least 60 seconds. Press on the edges,
ensuring that the patch has completely bonded to the tyre's
liner. It's not necessary to remove the clear plastic from
the patch you've just applied, but doing so will tell you
whether you've done a thorough job of bonding the patch. If
the patch begins peeling away as you try to remove the clear
film, the edges may not be fully glued.You can touch up loose
edges by carefully spreading a small amount of glue with the
tip of your finger.
Pinch-Flats
Though less common with tubeless tyres, pinch-flats can and
do happen. Unfortunately, patching a pinched UST tyre is
almost never successful. As such, it's a good idea to carry a
spare inner tube even though you may be riding tubeless.
Even if you never need it, you just might make the day of one
of your more old-fashioned-but-unprepared riding partners.
After removing the valve stem according to your wheel
manufacturer's method, installing a tube in a tubeless tyre
is no different than with any standard tube, tyre and rim
combination.
with a special valve cap or removal tool. This is handy to repair valve leaks.
Some presta valves have replaceable cores, too. If so, there are spanner
flats on the sides of the valve
Mount up. Align the tyre label with the valve stem and
mount the first tyre bead into place on the rim. Work the
second bead onto the rim. Pushing the bead into the centremost, deepest portion of the rim should make the last portion of the bead slip easily over the rim's wall.
Extra leverage. Use plastic tyre levers for the last short section
of the bead if it proves too much for your thumbs to handle.
Be gentle, and use the widest, flattest levers available. There's
no tube to pinch, but remember that you don't want to
damage that liner.
Air up. Check once more that all of both beads are nestled in
the centre of the rim. Getting the beads to move into their
seats is the trickiest part of UST mounting. Compressed air
works best, a floor pump is next best and a handheld mini
pump is little more than 30 cm (12 inches) of frustration.
Quickly pump the tyre to about 20 psi. At this point the tyre
should take shape and the beads should form a loose seal,
making the rest of the process easier. Slowly continue adding
air until the beads begin to audibly 'pop' into the bead seats.
Stubborn tyres can sometimes be coaxed into place. Grip the
inflated tyre with your palms near the point where the bead
will not seat and rotate your hands forwards.
Mounting a UST tyre
A tubeless tyre installs in a manner very similar to any tubetype clincher tyre.
Hey, slick. Start by spraying the inside of the rim with a
diluted soap-and-water solution. If you don't have a spray
bottle, apply the soapy water solution with a soaked rag or
paper towel.
Keep a sharp eye. Inspect the sidewalls for uniform seating
and keep adding pressure (up to a maximum of 60 psi) until
the bead-seat indicator (a textured ring that extends about
3 mm (h inch) above the rim wall on most tyres) is equally
exposed all the way around on both sides of the tyre. From
here, simply lower the pressure to your riding preference and
you're finished.
WHEELS AND TYRES
Tubular Tyres
Tubular, or sew-up, tyres used for road, track and sometimes
cyclo-cross racing are glued to the rim with a special contact
cement.This bond is critical because if a tubular comes off the
rim, a crash is almost guaranteed. Proper gluing is the key, and
the first step is cleaning the rim. Sand it lightly with emery
cloth to scuff up the surface and give the glue a little more
purchase. Using acetone or alcohol, clean the rim of any oil
or other contaminants.
For a new tubular, it's best to first put it on a rim without
cement, inflate it and let it sit.This stretches the tyre and makes
mounting easier when you're gluing it on. Start by putting a bit
of air in the tyre so it has a shape but no pressure. Then set the
wheel vertically on the ground in front of you, with the valve
hole on top. Insert the valve through the hole and grasp the
tyre on either side with your hands. Place each section onto the
rim, and advance down the sides, lifting each section of the tyre
onto the rim.
Bending over the wheel, continue to mount the tyre while
watching the valve to see that it remains straight. If it becomes
crooked, pull the tyre harder with one hand to correct. As
your hands near the bottom of the wheel, the tyre will
become tight. Use your body weight to stretch the tyre into
place. Pop on the last difficult section by lifting the wheel off
the ground and rolling that tyre section away and then onto
the rim with your thumbs.
Move around the wheel, straightening the tyre, and then
add full air pressure. Let the tyre sit for a while — preferably
overnight, but at least 10 or 15 minutes — to give it time to
stretch (the longer you are able to wait, the easier it'll be to
mount after gluing).
When the tyre has stretched, remove it from the rim. Place
the wheel in the bike, suspend the bike and dab the tubular
cement between each spoke hole on the rim. Put your index
finger inside a plastic bag, then hold it on the rim as you slowly
turn the wheel with your free hand and spread the glue into an
even coat that reaches from sidewall to sidewall. Then apply a
bead of glue to the centreline of the tyre's base tape. Spread this
glue to cover the entire base tape using an old toothbrush or
something that you don't mind tossing out afterward.
Allow the first glue coat to dry for an hour and then add
a second coat. Wait about 15 minutes for this coat to get tacky.
Then mount the tyre exactly as before. Work carefully so you
don't get glue all over the sidewalls of the tyres.You'll know
you did a good job of gluing if, when eventually punctured,
the tyre is nearly impossible to remove from the rim.
When mounting a tubular tyre on a used rim, you'll be
faced with a buildup of old glue on the rim. It's not necessary
to remove this old glue, but it's important to have a smooth
surface for the tyre or it won't sit properly when installed.You
also don't want any loose bits of dried glue that can prevent
the new glue from holding the tyre to the rim.
61
To prepare the rim, place it in the bike frame (the tyre
should already be removed) and turn it while scraping with a
tool that fits the shape of the tyre seat on the rim. Cone
wrenches often fit nicely here, but anything that fits the rim's
shape and has a good scraping edge will work. Spin the wheel
while you hold the scraper's edge against the rim to chip off
the loose glue and smooth the rim's surface. It doesn't have to
be perfect, just smooth and flat enough for a good glue purchase and for the tyre to sit properly on the rim. When the
rim is prepared, glue it as directed and mount the tyre.
Patching tubular tyres. Repairing tubulars is slow but fairly
easy work. When possible, locate the puncture while the tyre
is still on the rim. Inflate the tyre and listen for leaks. If you
don't hear air escaping, hold the tyre near your face and turn
it, trying to feel the air (this sounds nutty, but the skin on your
face is very sensitive). Look closely for a hole or cut in the
casing that is the point of the puncture. Once you locate it,
mark the spot so you can find it again quickly after you get
the tyre off the rim.
Unfortunately, some leaks can be extremely difficult to
pinpoint. If you can't locate the precise point of the problem
by one of the above methods, pull the tyre off the rim and try
another method.
If you have a slow leak, try pumping up the tyre and
immersing it in water, watching for bubbles. Unfortunately,
air bubbles sometimes travel inside the tyre casing before
emerging into the water, so this method isn't foolproof.
The most certain way of pinpointing the tyre leak is to isolate one section of the tyre at a time and see if any air escapes
from the rest of the tyre. If not, the problem lies in the isolated section. Try blocking off a section of tyre by squeezing
it between your hands. A more elaborate method is to clamp
a couple of short 4 x 2 (2 x 4-inch) blocks around the tyre,
section by section. Once you've located the source of the
problem, begin your repair.
A tubular tyre has protective tape called base tape over the
stitching that holds it together.This tape is bonded to the tyre
with liquid latex, not rim cement. Cut the tape and pull it
back to expose about 15 cm (6 inches) of stitching at the
location of the puncture. Mark the stitches with a permanent
marker so you can tell which holes line up across from each
other after the thread has been removed.
Use a sewing seam ripper or a knife to cut the stitching
threads. Pull the tyre open and remove the thread remnants.
Carefully pull aside any protective gauze or tape to expose the
tube. Lift out the tube and look for the leak. Patch the leak
using the same methods used for ordinary tubes. If it's a latex
tube (very thin and peach-coloured), it's possible to patch it
with a piece of latex cut from a discarded tubular tube. Just
apply glue to both the tube and the patch, wait for the glue
to dry and press them together.
WHEELS AND TYRES
wobbles or dents. A wheel can wobble for several reasons.You
must identify the source of the problem before trying to fix it.
Loose hub bearings. If you push laterally on the wheel and
feel play, the hub bearings have loosened. This makes truing
nearly impossible. Adjust the hub bearings before truing the
wheel. See Chapter 5 for instructions on hub adjustment.
Incorrect spoke tension. With experience, you'll be able to
find loose spokes by feel. Generally, loose spokes cause the
wheel to go out of true. The repair is as easy as retensioning
the loose spokes, but keep the following points in mind
whenever you begin to true your wheels:
You need not remove the tyre to true the wheel, but you
ought to release most of its air pressure. Otherwise, the
turning nipple may cut through the rim strip and puncture
the tube.
Beware of spoke wind-up while you turn the nipple. This
can occur when damaged or inadequately lubricated
threads cause the spoke to twist with the nipple instead of
threading into the nipple. Check for this by feeling the
spoke with two fingers while turning the nipple. Back off
to unwind the shaft if necessary.
Pliers and adjustable spanners are no substitute for the
right spoke key (there are four basic sizes). A damaged
nipple is undesirable and often can't be removed without
cutting and replacing its spoke. A spoke with a frozen
(rusted) nipple must be replaced.
Work in small increments. Adjust nipples only onequarter turn at a time to avoid making overcompensations
in spoke tension. Larger adjustments can be made if you
have the experience to know when they're appropriate.
The tension in neighbouring spokes on the same side of
a wheel should be similar. Pluck them to compare their
sounds.
If, to straighten a wobble, the correction calls for tightening a spoke that can't be further tightened or loosening
one that is already slack, then you're probably dealing with
a bent rim. If the spokes can't correct the bend, attempt to
forcefully rebend the rim and try truing again. Chances are
the rim will simply have to be replaced.
Broken spokes. Broken spokes must be removed and replaced
as soon as possible. It's usually best to replace the nipple as
well. If the wheel is otherwise undamaged, the replacement
will be very easy. With a rear wheel, the gear cluster (cassette)
63
may need to be removed. Thread a new spoke (get the right
length) through the hub and up to the nipple, copying exactly
the pattern of the other spokes.You may bow it considerably
for installation, as long as you avoid sharp bends near the
elbow and you make sure to straighten it afterward. Tighten
the new spoke until its tension resembles its neighbours
(pluck the spokes and compare their sounds).
Tighten further, if necessary, to straighten the rim at that
point.This process is usually as simple as retuning a radio station after the dial is mistakenly brushed. Tighten and loosen
only the new spoke until the rim runs true. On some very
light or excessively tight wheels, a broken spoke leaves a kink
in the rim that the new spoke can't correct. Sometimes the
wheel is lost, though often it's salvageable.
Dents and bends. Small dents that widen a rim cause choppy
braking action but can be eliminated by a gentle squeeze with
a smooth jaw vice. Avoid overcorrecting by squeezing only a
little at a time. Spoke readjustments can also help hide the
damage. Small dents on narrow clinchers can often be remedied by grabbing the bent rim bead seat with an adjustable
spanner, levering out and up.
Larger dents are serious business and require expertise.
One way to undent a 'fiat' spot in a rim is to release the spokes
at the point of damage and suspend the wheel off- the ground
with that position down. Slip between the spokes over the flat
spot a 4 x 2 (2 x 4-inch) block of wood that's about 30 cm (1
foot) long. Strike the wood with a hammer, pounding the
dent away from the hub.You may want to first carve the wood
to the shape of the rim where they contact.
Keep pounding until the rim is very slightly bulging.
Beware — it may take less force than you expect, so begin with
light blows. Some lightweight rims will fail when subjected
to this treatment, so don't assume success. If the correction is
more than 10 mm (j inch) or the rim ends up with cracks or
wrinkles, the result may be unstable and therefore unsafe.
Sideways bends are tricky to fix. A typical cure for a small
local bend is to release sonic of the spoke tension at the bend
and then remove the wheel from the bike or truing stand.
Kneel on the ground and lay the wheel on its side in front of
you with the bent section facing down and positioned nearest
you. Lean over the wheel and grasp the rim 20 to 25 cm (8
to 10 inches) to either side of the bent section, pressing it to
the ground. By applying some of your body weight, you can
force the rim back into shape. If you're lucky, you may be able
to retension the spokes and reuse the wheel.
Emergency Wheel and Tyre Repairs
So it looks like your wheel or tyre is beyond repair?
Never say never. If some mishap disables your bike, it's time
for emergency measures. Ty-re damage is the most likely
64
ILLUSTRATED BICYCLE MAINTENANCE
inconvenience. When you discover that your tyre casing has a
cut that is so large that the tyre can't hold the tube at pressure,
use an internal reinforcing patch. In an emergency, such a
`boot' can be made of scraps of clothing, high-fibre paper such
as currency or whatever is available. The less suitable the reinforcement, the less air pressure you can use before the tube
bulges out. If the casing damage is near one of the tyre's beads,
wrap a long piece of cloth around the tube next to the inside
of the tyre and circle it around the tyre's beads so that it will
be held between the tyre and rim when the tyre is reinflated.
Carry such a piece of reinforcement in your tool kit, something like a 13 x 25-cm (5 x 10-inch) rectangle of tough nylon.
A broken spoke must be removed as soon as detected or,
at least, wrapped around a neighbouring spoke to prevent
tangles. If the damaged wheel won't clear the brakes or
frame, some on-the-spot truing might help. A spoke key is
almost essential, but other metal grabbers like adjustable
spanners and pliers can do the trick in a pinch. Position the
spoke to be adjusted near the frame stays or fork. Use your
hand to pull the rim in the direction of the spoke that needs
to be tightened, grasping the rim and frame together and
squeezing. With such a deflection, the spoke will soon
become slack and easy to turn.
Taco'd rim repair. In the case of complete wheel collapse,
little can be done besides rebuilding. But, it's sometimes possible to straighten even badly damaged wheels well enough to
get you home by using one of a handful of brute-force techniques (sure to impress your ride partners). Two that we've
found to be most successful are highlighted here.
If the wheel assumes a very symmetrical 'taco' or 'potato
chip' shape, try bouncing it back to normal. Lay the wheel on
the ground and kneel over it, holding opposite edges of the
rim in each hand. Grab the high spots and press them down
forcefully. Occasionally, this will cause the wheel to spring
back to rideable condition. If so, consider yourself lucky. This
procedure may get you home, but the wheel still needs
rebuilding with a new rim.
If a skid or crash bends one section of rim badly out of
true, try inserting that section in a narrow slot and bending it
back into line by levering the rest of the wheel. Such a slot
can be a doorjamb, sewer grating or space between boulders
or trees. Use your imagination.
Whether you use such drastic methods or simply phone
home is your decision. But, don't forget, bicycles are tools of
survival and many irreverent and impromptu repairs have kept
them on their way.
TROUBLESHOOTING
Every time you fix it, the tyre goes flat again.
PROBLEM:
SOLUTION: Check the tube carefully. Are the holes in one
area? If they're on the bottom, the rim strip may be out of
position, allowing the tube to get cut by the spokes. If they're
on top, there may be some small sharp object still stuck in
the tyre. Find it by running a rag around the inside of the
tyre, and get it out of the tyre.
PROBLEM:
The tyre loses air slowly.
Put some spit on the Schrader valve and watch
to see if a bubble forms, indicating a slow leak. Tighten the
valve, or remove it and apply a drop of oil on the rubber
seal, then reinstall. If it's not the valve, remove the tube,
inflate it and hold it under water to find the hole.
SOLUTION:
PROBLEM:
You keep getting pinch-flats.
SOLUTION:
Put more air in your tyres, or install wider tyres.
PROBLEM: It's hard to install the tyres because the tube
gets in the way.
SOLUTION:
Tyre installation is easiest if you use a tube that's
narrower than the tyre. Switch to either thinner tubes or
wider tyres.
PROBLEM: You
got the tyre on but it won't sit right on
the rim.
Let the air out, wiggle the bad spot around,
reinflate to about 30 psi and roll the bad spot into place
with your hands. Then inflate fully. If this doesn't work, try
letting the air out, applying a soapy solution to the tyre and
reinflating.
SOLUTION:
PROBLEM:
The patch won't stick to the tube.
Put on enough glue and let it dry completely
(about 5 minutes). Never touch the sticky side of the patch
with your fingers. Don't blow on the glue to get it to dry
faster because you may get water on the glue.
SOLUTION:
PROBLEM:
You can't get air in your aero wheels.
Get tubes with long enough valves (they must
protrude enough to get the pump on) or get valve extenders.
Be sure to leave the presta valve unscrewed when installing
the valve extenders.
SOLUTION:
WHEELS AND TYRES
PROBLEM: Your
tubeless tyre loses air slowly.
65
Schrader, just drill the rim holes with a 6 mm (h-inch) drill
bit to enlarge them.
SOLUTION:
Remove the tyre and check the rim for foreign
matter in the bead channel. Ironically enough, one manufacturer's quality control sticker has a nasty habit of sliding into
the bead channel and causing a slow leak.
PROBLEM: You're
trying to upgrade wheels and you
discover that the new wheels won't fit into the frame.
It seems like they want to go but something is getting
hung up.
A dent or nick in the rim can also cause slow air loss. Aside
from rebuilding with a new rim, there is no way to repair
this. If the rim is still able to hold a tyre, you can use a
standard tyre and tube on a UST tubeless rim.
SOLUTION:
SOLUTION:
In order for any wheel to fit in a frame, the
over-locknut distance on the hub (measured from locknut
to locknut on the axle) must match the dropout-to-dropout
distance (the distance between the inside faces of the front or
rear dropouts) in the frame. Most front wheels are 100 mm,
while rears can be 120, 125, 126, 127, 130, 135 or 140 mm.
If you're trying to fit a too-wide hub, have the frame
realigned by a shop so the wheel will slide right in (this
works on steel frames only).
PROBLEM:
PROBLEM: You want to change a bike that has 27-inch
wheels to 700C wheels because that's what everyone
has today.
PROBLEM: You
finish repairing a tubular tyre and find
that you've created an S shape in the tread.
You stitched the tyre up using the wrong holes.
Cut your stitches and try again. Next time, mark the casing
so you'll know which holes to use when restitching.
You keep breaking spokes.
SOLUTION: Usually this is because the wheel is built of
poor-quality spokes. Replace them with better-quality
spokes, such as DT or Wheelsmith stainless-steel models.
PROBLEM: It's always a struggle to install the wheels
after removal. The wheel doesn't seem to want to fit
into the frame.
SOLUTION:
Remember to place the chain on the same cog
was on when you took the wheel off (usually the smallest
cog). If you're doing that and it's still difficult, the frame
dropouts may be bent, which can make wheel installation
a pain. Have a shop check and align them with special tools.
PROBLEM: The wheels won't stay true.
SOLUTION:
Proceed carefully. Before you spend any money,
try a friend's 700C wheels on your bike to make sure that
your brake pads can be lowered enough and adjusted to
strike the 700C rims properly. The brakes may not reach
because 700C rims are smaller in diameter than 27-inch
rims. If your brakes don't reach, stick with 27-inch wheels.
There's no big advantage to 700C anyway.
PROBLEM:
There's a creaking sound from the wheels.
It
SOLUTION: True them and make sure that the spoke
tension is sufficient and uniform. If the spokes continually
loosen, add a round of tension to the spokes, which should
stabilize the wheel.
PROBLEM: You're
about to head out on a ride when you
realize your only spare tube has a presta valve. Trouble
is, your bike is set up with Schrader valves.
SOLUTION: Take the tube along. The valve will fit loosely
in the Schrader-size hole in the rim, but it will still work
fine. In fact, you can get rubber inserts to downsize the rim's
valve hole if you want to switch to presta valves permanently.
Or. if you have presta-drilled rims and want to switch to
SOLUTION: The spokes may have loosened.Tighten them
slightly. If they're tight, the spokes may be moving slightly
at the cross, causing the sound. Lubricate each cross of the
spokes with light oil and wipe off the excess.
PROBLEM: You have a radial-spoked wheel (the spokes
travel directly from the hub to the rim without crossing
other spokes) on which the spokes continually loosen.
SOLUTION: Try adding tension to the spokes. If the spokes
loosen again, it's probably because of the spoke pattern.
Radial spokes take shocks more directly than spokes that
cross others, so they're more apt to loosen. To keep them
tight, loosen all the nipples, apply a light thread adhesive to
the nipple and retension the wheel.Your loosening troubles
should cease.
66
ILLUSTRATED BICYCLE MAINTENANCE
Wheel Removal
and Remounting
If your bike is equipped with quick-release hubs, removing the front
wheel is quite simple. First, open the brake quick-release lever to
spread the caliper arms wider so the tyre can pass between the brake
shoes without hanging up.
P
I
For cantilevers, squeeze the pads to the rim with one hand and lift the
end of the transverse cable.
For Shimano V-Brakes or similar brakes, release the 'noodle' out of its
pocket in the brake arm (see photo).
WHEELS AND TYRES
4
67
Disc brakes can become very hot during a ride and are also very
sensitive to oil contamination. The trace amounts of oil on your skin
can sometimes be enough to ruin a pair of disc brake pads. To avoid
unnecessary contact with the brake disc, consider mounting your quick-release
levers on the side opposite the disc.
-.AMMO.
MN.-
5
-,91=1111Pm
When locked, quick-release levers should be parallel with the bike
frame. Twist the lever in a 180-degree arc away from the frame.
The wheel should now drop out of the frame. If not, give it a push.
If that doesn't do it, the fork is probably equipped with a wheel-retention
device. To remove the wheel, hold one end of the quick-release and unscrew
the other end several turns to open it further and allow it to clear the stops.
If your wheel is fastened in the bike frame with nuts, loosen one of the nuts
slightly with a spanner. Then move the spanner to the other side of the wheel
and loosen the other nut in the same way. Or put a separate spanner on each
nut and break both free at the same time.
6
A rear wheel is a bit more complicated to remove because of the
chain and the cassette cogs. First, shift gears so that the chain is on
both the smallest chainring and smallest rear cog. Spread the brakes
and loosen the wheel.
Then, either lift the chain off the rear cog or pull the derailleur back to
help free the chain from the cog (see photo). Strike the wheel to dislodge it,
and move it down and out, disentangling it from the chain as you proceed.
Replace the wheels by following the same procedure in reverse order. Pull the
rear derailleur back to take tension off the chain while you install the wheel.
7
Centre each wheel in the frame and tighten it in place. If the wheel is
fastened with nuts, tighten each the same amount until both are very
tight. If the wheels are quick-release, push the levers into the locked
position to ensure that they're very tight and can't loosen accidentally. Finetune the quick-release adjustment by turning the nut on the opposite end of
the skewer before locking the lever.
Rotate the quick-release lever so that when open
it
points forward and when
locked it points toward the back of the bike. This eliminates the possibility of
the lever accidentally catching on something and loosening while you're riding.
68
ILLUSTRATED BICYCLE MAINTENANCE
Clincher Removal, Repair
and Remounting
Whenever a tyre goes flat and needs repair, don't ride on it any
:
urther. Push or carry your bike to a safe spot, then remove the wheel
ram the bike to repair the tyre. Before taking the tyre and tube apart,
mark the tyre next to the valve stem to establish the relationship between the
tyre and tube (or simply always place the tyre label by the valve stem). This
makes it easier later to locate any foreign matter that may still be embedded
in the tyre casing.
If any air remains in the tyre, let it out by pressing on the valve
(unscrew the tip of a presta valve first). Begin tyre removal on the
side of the rim opposite the stem to minimize chances of damaging
it. Squeeze the sides of the tyre toward the trough at the centre of the rim to
produce some slack, then hook a tyre lever under the edge of the tyre and
pull it over the rim. (Make sure your tyre levers have no sharp edges. Plastic
levers are less likely than metal ones to damage a tube.) Move a few inches
along the rim, hook a second lever under the same bead, and pull it over the
ri m (see photo). If necessary, use a third lever. Once you get several inches of
the tyre diameter over the rim edge, pull the rest of it over the rim by hand.
When one entire bead of the tyre is free from the rim, it's easy to
remove the tube for repair. There is no need to take the tyre completely
off the rim. Just push it over to one side while you remove the tube. Lift
the tube's valve stem out of its rim hole, being careful not to damage it, then
pull the remainder of the tube out of the tyre.
Pump some air into the tube and try to pinpoint the puncture by listening or
feeling for the escaping air. If a container of water is available (use a puddle
on the trail or road), immerse the tube in water and watch for air bubbles.
When you locate a repairable puncture, mark the tube at that point (dry it
first if it's wet).
WHEELS AND TYRES
69
1111111W
4
Pull the tyre off the wheel and lay it down. Spread the tube over the
tyre so the two are in the same relationship they were in the wheel.
Line up the valve stem with the mark you previously made on the
tyre. Then check both the inside and outside of the tyre casing at the point
of puncture. Remove any offending objects.
5
If you're unable to locate a puncture in the tube, check the valve
stem. Tubes on underinflated tyres can shift position, allowing the rim
to cut into the side of the stem. If the stem is cracked or cut, you'll
need to replace the tube.
"SW
6
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4111V
NM
Spread the tube on a table. Use the piece of sandpaper or metal
scraper from the tube repair kit to rough up the puncture area.
Brush off any dust with your hand.
Coat the roughed area of the tube with a fine, even layer of glue
that's a little larger in diameter than the patch you intend to use.
Make sure there are no globs that would prevent the patch from
sealing properly. After spreading the glue on your tube, allow it to dry
completely (this usually takes about 5 minutes).
70
ILLUSTRATED BICYCLE MAINTENANCE
Take a patch out of your repair kit. Choose a size that will cover
the puncture and make good contact with the area all around it.
Peel off the foil from the sticky side of the patch and carefully
fasten the patch in place on the tube.
To make sure you get a good seal, press down hard to force out any
air bubbles. Inflate the tube enough to give it shape. Push one bead
of the tyre back onto the rim, leaving the other bead and most of the
casing hanging off the rim while you replace the tube. Temporarily push the
second bead of the tyre over the rim at the valve hole and roll it back over
the first bead to uncover the hole
`
Fit the valve stem of the tube through the hole, then pull the
compressed section of the second tyre bead back over the tube
and off the rim. Starting in the area of the valve stem, work
your way around the rim, tucking the tube back inside the tyre. Once the tube
is in place, let the air out of it while you work the second bead of the tyre
onto the rim. Begin at the stem. With the first few inches of the bead in place,
push the valve stem up into the tyre to ensure no part of the tube around the
stem is caught under the bead. Then continue your way around the rim.
WHEELS AND TYRES
1
71
Try to avoid using tyre levers to put the tyre onto the rim.
You should be able to do it with your hands alone. If you use tyre
levers, you risk pinching the tube and damaging it. To get the
slack you need for the final part of the process, go around the tyre and
squeeze the two beads together so they will drop down into the trough in the
middle of the rim. When you get to the last section of tyre, you may find it
quite difficult to force it onto the rim.
Make sure you have given yourself all the available slack, then
I
g rasp the tyre with both hands and, using a vigorous twisting
..._ motion of the wrists, try to roll the stubborn bit of bead over
the edge of the rim (see photo). If this technique does not work for you, push
the bead onto the rim bit by bit with your thumbs or the heels of your hands.
13
Once the tyre is on the rim, push the valve up into the tyre
and pull it back down to be sure the stiff portion of the tube
surrounding the valve is not trapped beneath the tyre bead.
Then, work around each side of the rim, rolling the tyre back and looking
to see if the tube is trapped beneath the tyre bead anywhere else. If it is,
the tube will get pinched and the tyre won't seat properly when you inflate it
(use a tyre lever to poke the tube into the tyre). If everything looks okay, pump
20 to 30 pounds of pressure into the tube. If the stem is still straight and the
tyre is seating properly, continue pumping up to the recommended pressure
(usually printed on the tyre label).
72
ILLUSTRATED BICYCLE MAINTENANCE
UST Tubeless Tyre Removal,
Repair and Remounting
1
UST tyre service is remarkably similar to any other clincher. In the case
of a flat, stop riding and walk your bike to a safe spot to make the
repair and remove the wheel from the bike. Pinch the sidewalls
together firmly to get one of the tyre beads to pop out of its channel. Then
determine which bead has dislodged and work your way around the wheel,
pushing the rest of this bead into the centre of the rim.
2
1111111111•111111MIEW
. ....W...
- 41111111M.
The rim's diameter is smallest in the centre. With the bead in this
position, you can now pull the tyre up and away from the rim on one
side, freeing the bead from the rim. Avoid the temptation to use tyre
levers except as a last resort. Using tyre levers on a tubeless tyre or rim can be
damaging and render the system no longer airtight. If you must use tyre
levers, be extremely careful and use broad, flat plastic levers.
Check the tyre inside and out for the cause of the puncture, mark it,
3
and remove it. On the trailside, the quickest way to get back rolling is
4-- to remove the valve stem from the rim (see photo) and install a tube in
the same manner you would any other clincher tyre (as described in 'Clincher
Removal, Repair and Remounting' on page 68). You can then continue with the
rest of these steps in the comfort of your home workshop.
WHEELS AND TYRES
4
73
Push the second bead free of its channel in the same manner you did
the first. Once the second bead is dislodged and in the centre of the
ri m, the tyre should easily come off the rim.
Turn the tyre inside out at the point of the puncture and scuff it heavily with the
coarse sandpaper or rasp included in your patch kit. Scuff an area on the
inside of the tyre around the hole slightly larger than the patch you intend
to use to repair it.
IMP
OW
4101a
.1118111111.11111111MIMMIN
10111W
HENNIMIllik
Apply a gob of glue and spread it around the rough area. Let the
glue set up for several minutes. You're ready for the next step when
5 the glue goes from clear to cloudy.
6
Remove the foil backing from the patch and firmly press the coloured
(usually orange) side of the patch into the glue. Keep constant pressure on the patch for 2 to 3 minutes, then carefully peel the clear
plastic from the patch. Though it can be left in place, removing this film will
help you be sure the patch is completely vulcanized to the tyre's lining. If the
edges of the patch peel up, spread a small amount of glue over the top of the
patch and smooth the edges down from the middle outwards.
74 ILLUSTRATED BICYCLE MAINTENANCE
7
While the patch dries, reinstall the valve stem and prepare the rim.
Clean the rim out with a clean cloth to ensure a good seal with the
tyre. Spraying a diluted soap-and-water mixture into the rim will
make the tyre's beads pop into their respective channels more easily and
help to maintain a good seal. If you don't have a spray bottle for this purpose,
use a clean rag or sponge soaked in the same mixture.
8
■M■W-
A1Mit
When the patch is dry, mount the tyre. The first bead should slip into
place easily. The starting point of the second bead is less important
than with a tube-type tyre, but it's slightly easier to start opposite
the valve stem. Hold the wheel in your lap with the free bead facing up. Set
the bead into the rim's centre opposite the valve and then work the bead over
the rim wall little by little using your thumbs, moving away from each other
around the wheel.
WHEELS AND TYRES
9
75
As the last section of exposed bead becomes tight, recheck that the
rest of the bead is settled into the centre of the rim. Hold the wheel
into your waist with the last section of bead away from you and grip
the tyre firmly on both sides of the still exposed section of bead. Roll your
hands forward to stretch the last bit of bead over the rim. Though some tyres
may prove difficult, give it your absolute best shot to finish without using
levers. Remember; there's no tube to pinch, but you don't want to compromise
an expensive UST lyre. Got it? Good!
With the tyre mounted, check once more that both beads are set down in the
ri m's centre. Using a floor pump or compressed air, quickly pump the tyre to
about 20 psi. The UST system requires a quick burst of air to create the initial
seal between tyre and rim. It's possible to achieve this with a mini pump, but
it's more likely to only cause aggravation.
Once the initial seal is created, pump the tyre steadily, listening for the beads
to pop into place. When this begins, inspect the tyre every few strokes until
the bead is seated evenly all the way around the wheel. Once the tyre has
reached about 40 psi, you can help the process along by gripping the tyre
with the heel of your hand near a section that hasn't popped into place and
pushing away with steady, even pressure. If necessary, keep inflating the tyre
up to (but not beyond) 60 psi.
When the bead seat indicator (a textured line that extends about 3 mm
beyond the rim wall) is fully and evenly exposed, that's it. Set the
tyre to your chosen riding pressure, reinstall the wheel, and go for a ride.
76
ILLUSTRATED BICYCLE MAINTENANCE
Tubular Removal, Repair and
Remounting
When a tubular tyre goes flat, stop riding on it immediately. Take the
wheel off and pump a little air in it to try to locate the puncture while
the tyre is still on the rim. If you find the leak, mark the spot and proceed with the removal of the tyre from the rim. If not, you'll have to pull the tyre
off the rim. If the tyre was glued on properly, it won't come off the rim easily.
Try gripping one section of the tyre with both hands and rolling it over the side
of the rim, pushing on its underside with your thumbs or palms. If you weren't
able to find the puncture while the tyre was on the rim, pump some air back
into the tyre, then hold it near your ear and listen for a leak. Even if you can't
hear anything, you may be able to feel the escaping air against your face.
If you couldn't locate the escaping air otherwise, immerse the tyre
in water and watch for escaping air bubbles. Once you see, hear, or
Aemiet feel escaping air, search for evidence of a puncture. Until you actually
locate the puncture you can't be certain where the problem lies, because air can
travel out of a hole in the tube and move several inches inside the tyre before
emerging. The most foolproof way of isolating a leak is to clamp off a small
section of tyre, then pump air into the tyre. If air escapes from the tyre, loosen
the clamp and move it along to another section. When no air escapes from the
unclamped part, you know the problem lies within the clamped section. Take
off the clamp and inspect that section to discover the source of the leak.
It's important to know precisely where the tube needs repair before
cutting the stitching because you want to keep to a bare minimum
the area you have to cut and later restitch.
Once you've located the puncture, lift up a few inches of base tape in that
area (see photo). The base tape covers the tyre's stitches and is bonded to the
tyre with latex glue. This is different glue than the glue used to mount the tyre
to the rim. When the stitching is exposed, make a distinct mark across the
seam to help you line up the edges of the tyre for later restitching.
WHEELS AND TYRES
4
5
77
Use a sharp knife, razor blade, or (best of all) sewing seam ripper to
cut enough stitches to enable you to pull out the section of tube that
needs to be repaired.
Pull out that section of tube and rough up the punctured area
with fine sandpaper. Spread a layer of patch glue over the area
and let it dry completely (it'll lose its glossy appearance, usually
after about 5 minutes).
6
7
INIMININE
Find a patch of the appropriate size and peel off the protective backing
from its sticky side. In order to get a good seal, place one edge of the
patch on the tube first, then roll the remainder of the patch over.
Sprinkle a bit of talc over the patched area to prevent the tube from
sticking to the tyre. Check both inside and outside the tyre to locate
and remove any remaining foreign material that may repuncture it
once it's inflated and back in use. If any threads of the tyre casing have been
severed, cut a piece of strong canvas, nylon, or old tyre casing and insert it
inside the casing over the damaged area. When the repaired tube is inflated,
it'll hold the patch in place. Push the tube back into place inside the tyre.
Straighten the inner tape over the tube, then pull the edges of the casing
together, lining up the two halves of your mark.
78
ILLUSTRATED BICYCLE MAINTENANCE
8
Restitch the tyre using the original holes. (Creating new holes will
weaken the casing.) Be sure to begin by overlapping the old thread
for several holes on either side of the repair area. If you're a talented
ewer, you may want to try to duplicate the original thread pattern in the
yre. However, a simple overhand stitch will work adequately (see photo).
ubular-tyre repair kits provide thread, but any strong thread should work.
iome people prefer dental floss to the type of thread found in most kits. Just
ie a small knot in the end of your thread as if you were sewing on a button,
Ind tie off the other end when you complete the stitching. Fasten the base
ape with liquid latex.
-.........,
9
Carefully scrape dried old glue off your rim as well as possible (you
needn't get it all off). If it's a new rim, sand it lightly with emery cloth,
clean it with acetone or alcohol, and add a layer of glue. If you've
ever put a tubular tyre on a rim before, you may want to practice putting
on without glue first.
et the rim down on a clean floor with the valve hole at the top. Insert the
alve through the hole, and, beginning at that point, stretch the tyre around
he rim, working in both directions at once.
10
When you get to the last difficult section, lift the rim off the floor
and simultaneously stretch and roll the final part of the tyre over
and onto the rim (see photo). Work your way around the rim,
checking to make sure the tyre is on straight. When it looks right, inflate it.
If the tyre was difficult to get on, let it sit for a while, perhaps overnight, to let
it stretch a little. Then deflate the tyre and remove it from the rim for gluing.
WHEELS AND TYRES
11
79
Apply a dab of tubular cement between each spoke hole on the
ri m. Then run a bead of glue all the way around the rim. Apply a
lighter coat to the base tape of the tyre.
12
Put a small plastic bag or a piece of plastic over your fingers
and spread the glue around. After an hour, apply a second coat
of glue in the same way. When the second coat is tacky, pro-
ceed with the tyre mounting. When you set the rim down, be sure the floor is
clean because you don't want to contaminate the glue (or floor).
Roll the tyre onto the rim as you did before, then spin the wheel and sight
the tread to make sure the tyre is on straight and that it's properly centred.
If necessary, work it straight with your hands. Partially inflate the tyre and
put it on your bike. If everything looks fine, inflate the tyre to full pressure
and let it sit overnight before being used.
80
ILLUSTRATED BICYCLE MAINTENANCE
Rim Maintenance and Repair
I
Basic wheel maintenance includes cleaning your rims regularly
because the road grime that builds up interferes with good braking
, performance. Wash rims with soapy water, as you would a car.
To break up the residue that remains on the rims, use a solvent such as
kerosene and fine steel wool or an abrasive pad made of material that
won't scratch metal.
Take care not to get the kerosene on your tyres or brake pads. Use a milder
solvent such as alcohol to clean the grime off your brake pads.
2
,,.....,
......F
Not only do rims get dirty but they also frequently get scratched
or dented. If the dents are not too severe, you may be able to
squeeze them out. Remove the tyre from the rim and fasten the
dented section of the rim between the jaws of a smooth jaw vice. Tighten the
vice to squeeze out the dent. You may be able to straighten a minor bend in
the edge of the rim with the help of a small adjustable spanner. Screw the
jaws of the spanner down snugly against the rim and lever the rim in the
direction needed to straighten it.
3
..m.wt
AM*
Large dents or bends that result from a crash are more of a challenge
to correct. There's no guarantee you'll be successful, but it's usually
worth the effort to try to salvage an expensive rim. First, remove the
tyre from the wheel and loosen the spokes in the affected area, then set the
ri m vertically on the ground and run a heavy stick or a length of lumber over
the dented-in area. Position your feet on the stick, one foot to either side of the
rim. Bend your knees, grasp the upper part of the rim with your hands, then
straighten up, pulling the rim back into shape (see photo).
WHEELS AND TYRES
4
Sideways bends can be handled in a similar manner. Begin by easing
the tension off the spokes around the trouble spot. If you have a big
bulge at one spot, set the edge of the rim on a workbench and try
pounding it out with a mallet. If the bend is over a fairly large area, place
one hand 20 to 25 cm (8 to 10 inches) on either side of the problem area,
then hold your knee against the bulge in the rim and pull back on the rim
to pop it back into round (see photo).
If you're lucky, you will eliminate the unnatural tension in the rim, and you
can use spoke adjustment to bring it back into usable shape. But if not, at
least you tried.
5
81
Take extra care with high-performance, low-spoke-count wheels.
Wheels such as these rely on extra-high spoke tension to maintain
strength. Too great a disparity in spoke tension on these wheels can
make them very unstable. They are not drastically different to work on than
conventional wheels, but if you are uncertain about your abilities, it may be
best to leave them to a professional.
82
ILLUSTRATED BICYCLE MAINTENANCE
Spoke Maintenance and
Replacement
1
The spoked wheel is a marvellous invention. When properly built and
maintained, it's incredibly strong; when improperly adjusted, it's very
vulnerable to damage.
Spokes don't demand a lot of maintenance. Your main job is to make sure
they're properly tensioned. Periodically, work your way around each wheel,
plucking each spoke to make sure that it's not loose. You'll spot a loose spoke
both by the way it feels and by the way it sounds when plucked (see photo).
When you locate a loose spoke, use a spoke key to bring it up to a level of
tension that is similar to that of its neighbours. After you've tightened any loose
spokes, check the wheel for trueness and make further adjustments as needed.
Consult the instructions beginning on page 84 for more details on this process.
Wheel truing is easier when it's done on a special truing stand. If you don't
have such a stand, use your brake calipers to help you check your wheel.
Sighting between the brake pads and the rim will allow you to see whether
or not the wheel needs side-to-side truing.
2
Vertical trueness can be checked by fastening a straight edge to the
frame or the brake just above the wheel or by resting your thumb
above the rim. Spin the wheel and look to see if it's out of round.
When a spoke breaks, it's best not to ride any further on the wheel. Instead,
push your bike to a place where it's safe to replace the spoke. If you must ride
the bike, first weave the loose spoke end around an adjacent spoke, and then
ride slowly to your destination.
Remove the broken spoke and replace it with one of the same size. Run the
new spoke through the hub flange in the same direction as the old one. If you
need a new nipple, roll the tyre back, lift up the rubber strip that covers the
tops of the nipples, and take out the old nipple. Drop a new one in its place.
WHEELS AND TYRES
83
r
i
Pull your new spoke through the flange until its curved end is
seated, then weave it through the other spokes, following the pattern
of the old one. If in doubt, follow the pattern of the second spoke to
either side of it.
Before threading the new spoke into its nipple, apply a small amount
of oil to its threads. This will make it easier to thread the spoke into
the nipple and will help prevent it from freezing in the nipple over time
(see photo). Then thread it on and use a spoke key to bring it up to tension.
When working on spokes, it's important to use a key of the correct size. If
the flats on a nipple get worn round, you'll have a difficult time adjusting
that spoke. Also, before adjusting any of the old spokes, it's a good idea to
spray a little penetrating oil at the points where the spoke enters the nipple
and the nipple enters the rim. Rotate the wheel so that the oil will flow down
into the threads after you spray it on.
84
ILLUSTRATED BICYCLE MAINTENANCE
Truing Wheels
1
Wheel truing can be done most accurately with the tyre off the wheel
so the outside perimeter of the rim can be closely checked for roundness. If the tyre is on the rim at the time you wish to true your wheel,
simply let out most of its air to minimize your chances of puncturing the tube
while twisting a spoke nipple.
Mount your wheel in a truing stand and adjust the calipers so that their tips
are close to the sides of the rim. Spin the wheel and readjust the calipers to
move them as close as possible to the rim without hitting it at any point in
its revolution.
Start the truing process by working your way around the wheel,
beginning at the valve or some other reference point, and plucking
each spoke in turn to see if any are unusually loose (see photo). Bring
each loose spoke up to a level of tension similar to that of its neighbours.
Spray a little penetrating oil where the spoke enters the nipple to help the
nipple turn, and use a spoke key of the proper size so you don't round over
the sides of the nipple. As you tension each spoke, place one or two fingers
on the spoke to ensure it does not turn with the nipple. If it does, back off the
adjustment to eliminate this windup and try again. Tension caused by spoke
windup will be released when you use your wheel, ruining your adjustment.
Spin your wheel to check for horizontal trueness. To pull the rim to the right
at any point, loosen the spoke or spokes that run from the left side of the hub
to that point on the rim and tighten the spokes on the right side. Reverse the
procedure to pull the rim to the left.
WHEELS AND TYRES
3
85
Tighten and loosen opposing spokes the same amount, and work
in small increments of one-quarter to one-half turn each time. After
working all the way around the wheel once or twice, you should
have the wheel fairly true horizontally.
4
Check for vertical roundness in the wheel. If your tyre is on the rim,
check this by hooking a caliper over one of the inside edges of the
ri m, spinning the wheel, and looking for high and low spots. If the
tyre is off the rim, set the caliper (or other gauge provided on your truing stand)
near the outside edge of the rim, then watch for changes in the distance
between the gauge and the rim as it spins (see photo).
To eliminate high spots in the rim, tighten the spokes that meet the rim at
those spots. To eliminate low spots, release some of the tension on the spokes
in those spots. This time, tighten or loosen the spokes in pairs, one right-side
and one left-side spoke in each pair.
Remember, when you add or subtract tension from any section of the rim,
you're affecting the tension on other parts of the rim as well. So work in small
increments and recheck the trueness of the rim frequently. Alternate between
horizontal and vertical truing until you see only very minor variations in the
ri m's movement in either direction as it spins.
CHAPTER 5
Hubs
While some may argue the point, many more would agree
that the single most significant upgrade you can make to any
bike is a pair of smooth-spinning, high-quality hubs. The hub
occupies the centre of your wheel and is the foundation of a
well-built wheelset.
Hubs perform two critical functions. They house the axles
and bearings on which your wheels spin, and they anchor the
spokes that hold your rims round and true. With regular
maintenance, a quality hubset can outlive several pairs of rims,
sometimes even several framesets (we've seen 50-year-old hub
sets still spinning smoothly).
Though the hubs may appear intimidating because the parts
are hidden inside, the mechanisms are pretty basic. With a little
practice and the right tools, anyone can service most types.
Hub Construction
Before beginning to disassemble a hub, it's important to
understand how it is put together. Most are of the conventional adjustable cone-and-race variety. Hubs of this design
come in all price ranges and are easily serviced. Replacement
parts are available at most bike shops.
The largest part of a hub is the shell.The shell is the part to
which the spokes are attached, and it encases the working parts
— that is, the axle and bearings.The part of the shell that holds
the heads (the flared ends) of the spokes is called the flange.
Flanges come in different sizes, depending on the intended
purpose of the wheel. Though it's hard to discern through a
fat mountain bike knobby tyre, generally speaking, the larger
the flange, the stiffer the wheel. Road sprinters often want stiff
wheels because they like the rigid feel when they get out of
the saddle and accelerate towards the finish line. Mountain
bikers often use medium-flange hubs for a nice mix of stiffness
and comfort.
Hubs are sometimes described by mechanics by the type
of flange they have.You may hear them called high- or largeflange, medium-flange and low- or small-flange.
For most applications, the following rule applies: if you
want a comfortable wheel, consider using a smaller-flange
hub; for a stiffer wheel, use a larger flange. The actual strength
of a wheel, however, is determined more by the type of
spokes, the rim and the spoking pattern employed than by the
size of the hub flange.
Inside the hub shell are two bearing races, one at each end.
The bearings roll on the surfaces of the races and are held in
place by the cones, which screw onto the axle. The bearings
also roll on the surfaces of the cones. Because of the special
shapes of the races and the cones, the bearings roll in a circular path. The cones fit on the axle and are held in place by
a series of washers and a locknut.
The axle on a front wheel hub fits into slots cut into the
tips of the front fork; on a rear hub the axle fits into slots in
the rear fork, called dropouts. A hub is held in place on a
bicycle frame either by means of an axle and a pair of axle
nuts or by a quick-release unit consisting of a hollow axle, a
skewer, springs, a cam lever and an adjusting nut. Nuts must
be tightened and loosened by means of a spanner, whereas a
quick-release mechanism permits wheels to be locked in
place or removed without any tools.
Downhill and freeride bikes often come equipped with a
new design of axle called a through-axle. A through-axle is a
large-diameter axle that passes through substantial fork leg
ends or rear dropouts (for lack of a better term) and the hubshell. The through-axle is firmly clamped in place, creating a
strong, stiff connection. The purpose of through-axles is first
to resist independent movement of the fork legs or rear triangle halves on long-travel suspension designs. Additionally,
by clamping the axle all the way around, through-axle forks
are able to fight the force of powerful disc brakes that can try
The flanges to which spokes are anchored differ in size on different
hubs. They are usually referred to as 'low-flange', 'medium-' or
' mid-flange', and 'high-flange'.
LOW-FLANGE HUB
HIGH-FLANGE HUB
88
ILLUSTRATED BICYCLE MAINTENANCE
Anatomy of a Hubset
QUICK RELEASE
END NUT
i QUICK RELEASE
SKEWER
I VOLUTE SPRING
(QUICK RELEASE SPRING)
HUBS
to pull the axle out of a conventional fork dropout. The standard dimension for front through-axles is 20 mm in diameter
and 12 mm for the rear (with a few exceptions that use 24
mm front axles or 15 mm in the rear). Fortunately, frames and
forks that do not conform to the accepted standards usually
come equipped with hubs that fit.
Checking Hub Adjustment
To check hub adjustment, remove the wheel from the
bicycle.The front wheel is easy to remove. Unbolt the axle or
flip the quick-release lever to the open position and drop the
i wheel out of the fork.
If you have sidepull brakes, you may have to open the
caliper arms a bit to get the tyre past them. Most sidepulls
have a quick-release mechanism — a small lever that, when
thrown, opens the caliper to permit the tyre to go past. Most
cantilever brakes have a transverse cable (the wire that runs
from one side of the brake to the other) that can be released
from one side of the brake to spread the pads for tyre clearance. For direct-pull brakes, release the metal noodle from its
holder to open the brake. If your brakes don't have these features, deflate the tyre until it is soft enough to squeeze past the
brake pads.
Removing the rear wheel means dealing with the gears and
chain. Open the brake for tyre clearance as described above.
Then shift the chain onto the smallest cog on the cassette and
the smallest chainring on the crankset. Loosen the axle nut or
the quick-release lever. While holding the rear of the bicycle
off the ground, pull back on the body of the rear derailleur and
sh the rear wheel down and forwards to get it out.
Once the wheel is off, grasp one end of the axle with the
umb and index finger of your dominant hand.Turn the axle
wly for a few revolutions. Does it feel rough and seem to
tch in pits as you turn it? If it does, it's either too tight or
the hub is full of dirt or corrosion. If your hub doesn't feel too
tight, check it for looseness. Grab the axle again, only this
time wiggle it up and down and from side to side. If the axle
moves in these directions, causing a slight knocking feeling,
then it's too loose.
If the hub is too tight or too loose, adjust it.To continue to
ride it while it's out of proper adjustment will subject its parts
to unnecessary wear and will limit how well the bike can perform. For instance, a loose rear hub can affect shifting, while
tight hubs may make clicking sounds.
Adjusting the Hub
djust the hubs with the wheels off the bike. Don't even
- k about removing the hubs from the wheels, though.The
: time that's necessary is when you're replacing a hub, a
tin or a set of spokes.
You'll need only a couple of tools to make a hub adjustment: a spanner to fit the axle locknuts and a special spanner
89
for the cones. A cone spanner is a thin spanner that fits into
the narrow spanner slots on cones while a regular spanner is
on the adjacent locknut. Regular spanners are too wide to fit
side by side in this way. Cone spanners are available from
some bicycle shops.They range in size from 12 mm to 19 mm
and often come in sets.
Usual measurements are 17 mm for axle locknuts, 13 mm
for front cones and 15 mm for rear cones, but always check to
be sure. It's also possible to use an adjustable spanner for the
locknut. Some hubs may require two cone spanners because
the axle locknuts are slotted like cones and accept cone spanners, not regular spanners. Before you buy an extra cone
spanner, check the hubs to be sure you really need one. For
these instructions, we'll assume you're using one cone spanner
and one regular spanner.
SHIMANO 105
QUICK-RELEASE HUB
HOPE BIG'UN
THROUGH-AXLE HUB
SURLY SINGLESPEED
SOLID-AXLE HUB
Axles can be held in place in several ways. Most common on modern
bicycles are quick release (OR) axles that use a cam-action skewer to
grip the frame or fork dropouts on the axle. Solid axles use nuts to
achieve this goal, while through-axles have a large diameter axle that
is clamped in place on specially designed forks.
90
ILLUSTRATED BICYCLE MAINTENANCE
To adjust a rear hub that has a freewheel, remove it. (See
page 142 for instructions on freewheel removal.) Once the
freewheel has been removed, you can begin the adjustment.
If you have a cassette rear hub (one where the freewheel
mechanism is built into the hub), you may not need to
remove the cluster of gears to adjust the hub. It's a good idea,
however, to check the gears for tightness because they can
loosen with use, and this can affect shifting.
Follow the hub-adjustment procedure recommended on
page 92, but don't be intimidated if you don't get it perfectly
right on the first try. Almost nobody does.
If, after repeated tries, you simply cannot find the magic
line between loose and tight, leave the adjustment slightly on
the tight side. It may loosen a bit when you ride. But don't
settle for less than perfection in the adjustment until you've
made careful and repeated attempts to get it just right. The
time spent learning to make sensitive adjustments to the hubs
will pay off because similar techniques are used on headsets
and some bottom brackets and pedals. Look at attempts at
hub adjustment as valuable training in general bicycle repair
and maintenance.
,r auto parts stores. Other 'poor-man's seals' that work well
re pipe cleaners and butcher's twine. Simply wrap a pipe
leaner or tie a piece of twine around the area next to the
one to keep out contaminants. (Add one of these seals only
fter completing the hub-adjustment process.)
If the hubs have small holes in the dustcaps or hub bodies.
se the holes as a quick way to repack the hubs with fresh
rease.You'll need a grease gun with a needle injector to get
rease into the holes. Stick the end of the injector into each
ole and pump grease in until the dirty grease is forced out
f the bearing through the opening around the cone. When
lean grease starts to appear, simply wipe away the dirty
rease, and the hubs are ready to roll.
If you purchase new quick-release hubs that feel silkynooth, with no play in the axle, they're probably adjusted
m tight for actual use. The adjustment you feel is actually for
le manufacturer's quality-control checks. It's important to
Ad some play to compensate for the compression caused by
le quick-release skewer when the wheel is mounted on the
ike. Skip this step and the hubs will spin with extra resistance
ad suffer premature wear.
Hub Overhaul
hopping for New Hubs
Check hub adjustment and make any needed changes about
twice a year.To ensure long hub life, perform a complete hub
overhaul at least every other year for road bikes, and at least
annually for mountain bikes ridden off road. Or, if you rack up
4,800 km (3,000 miles) a year or so, figure that the hubs ought
to get a good cleaning and relubing annually. Also, if for some
reason the hubs are completely submerged in water, overhaul
them at the first opportunity — water can rust the bearings and
races, ruining the hub.
Only hubs that don't use precision or sealed bearings need
this periodic overhaul. Hubs that use seals to protect the bearings from contaminants may be able to go much longer
without an overhaul.
To overhaul hubs, use the same cone spanner and regular
spanner as in the hub adjustment. In addition to that, find or buy
a large flat-head screwdriver or tyre iron, medium-weight grease
that's not vegetable-based and new bearings of the appropriate
size and number (there are usually 18 of the h-inch ball bearings
in rear hubs and 20 or 22 of the X6-inch bearings in front hubs).
Bearings are not very expensive to replace, so avoid hassle
and use new ones. Be certain to install bearings of the same
size and number as you are currently using (take samples to
the shop to match the new ones with the old).
To overhaul hubs, follow the steps on pages 94-100.
Vhen purchasing new hubs, consider these factors.
Special Hub Tips
To make hubs more resistant to water and dirt, slip rubber 0rings over the ends of the axles and push them up against the
openings around the cones. 0-rings are available at hardware
lange height. The flange height affects the feel of the
icycle a little bit. On road bikes, the larger the flange, the
lore road shock you may feel, though this is usually a
roblem only on long, bumpy rides. For shorter rides, there's
o need to consider this factor. Due to fatter tyres that offer
)me shock absorption, flange height isn't that important on
mountain bike.
ealed or conventional bearings. Both are excellent. We
commend purchasing well-tested, established designs. Ask
de partners and shop personnel, and get hubs that have a
a nd reputation. Conventional bearings are usually easier to
rvice, but sealed models usually require service less often.
efore purchasing sealed-bearing hubs, inquire about special
)ols and techniques, along with the warranty.
vailability of replacement parts. It doesn't do much good
buy expensive hubs if 3 years later you have to replace
Lem because replacement cones aren't available.
assette versus freewheel. There are two main hub types:
tssette and freewheel.These are named according to how the
cluster attaches to the rear hub. Cassette hubs, the most
)mmon today, have freewheels built into the hubs. Freeheel hubs, with threaded-on gear clusters, were the norm
,r years but are now rare on new bikes.The advantage of the
issette system is that the hub bearings are further apart,
HUBS
which increases axle strength. On freewheel hubs, any gear
cluster that fits your hub will work.Today, however, fewer and
fewer manufacturers are making freewheels. At this point, the
best bet is to go with cassette-style hubs.
Axle width. Cassette hubs come in six-, seven-, eight-, nineand now ten-speed models. Each is equipped with the
proper-length axle. For freewheel hubs, a different width
(length) of axle is needed for five-, six-, seven- and eightspeed freewheels because the more cogs on the freewheel, the
more space it takes up on the axle. This means that, when
purchasing freewheel hubs, it's necessary to tell the shop
the number of cogs on the freewheel, so they can install a
different axle if necessary.
111F
SOLUTION: You may have put too many or too few
bearings or the wrong-size bearings in the hub race. There
are usually 9 bearings of the a-inch size in each side of
the rear hub and 10 bearings measuring 3/0 inch in each
of the two front races.
PROBLEM: Your
sealed-bearing hub has a trace of
side-to-side play when you push the wheel sideways.
SOLUTION:
Don't worry about it. This is acceptable.
PROBLEM: Your sealed-bearing hub has developed a
lot of lateral play that you feel when pushing sideways
on the rim.
Learning to overhaul and adjust hubs is not difficult and is a
good way to get started maintaining and repairing a bike. Once
you experience the payoff from your effort — smooth-rolling
wheels — you'll want to move on and master other areas of
bicycle maintenance as well.
SOLUTION: The cones may be worn. Replace them if
possible. Or have the hub checked by an expert or the
manufacturer.
TROUBLESHOOTING
SOLUTION:
PROBLEM: The wheel pulls out of the frame when
you're climbing hills.
91
PROBLEM: It's harder than usual to close and open the
quick-release.
Remove the quick-release and lubricate it with
a penetrating oil. If this doesn't help, the quick-release may
be worn out. Replace it.
PROBLEM: After
SOLUTION:
Loosen the axle nuts or quick-release, centre
the wheel in the frame and tighten the axle nuts or quickrelease tighter than before.
PROBLEM: You clamp the quick-release but it doesn't
bold the wheel tight in the frame.
SOLUTION: The axle has to be just the right length for the
quick-release to work. Leave the wheel in the frame and
Itemove the quick-release. Look at the axle ends. Do they
protrude past the outside faces of the dropouts? If so, remove
e wheel, file the axle down until the ends are within the
pouts and reattach the quick-release.
PROBLEM: There's play in the hub when you push
laterally on the wheel, but the hub is adjusted right.
SOLUTION: You may have broken the axle. Remove the
quick-release and pull on the axle to see if it's broken.
Replace the axle if it is.
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you can't get the adjustment right. It's either too
tight or too loose.
a hub overhaul, the wheel won't sit
straight in the bike.
SOLUTION:
Make sure that the springs on the quick-release
are installed correctly. The narrow end should always face in.
PROBLEM: After a hub overhaul on a nutted wheel,
the rear derailleur doesn't shift correctly.
SOLUTION: Nutted wheels should always have a washer
between the nut and frame. If this washer mistakenly gets
between the frame and hub, it'll change the spacing and
ruin the shifting. Remove the wheel and put the washer
where it belongs.
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ILLUSTRATED BICYCLE MAINTENANCE
Adjusting Cone-and-Locknut
Type Hubs
1
Cone-and-locknut hubs are the most conventional type of bicycle
hubs, even today. Ball bearings ride between a hardened steel cup
fitted in the hubshell and a hardened steel cone threaded onto the
axle. The adjustment is maintained by a locknut that threads against the cone,
preventing it from simply spinning out of place. Whether front or rear, freewheel or cassette, all cone-and-locknut hubs adjust in the same basic manner.
Adjusting rear hubs can require one additional series of steps relating to the
cassette or freewheel, so we'll focus on them here.
To start, remove the wheel from the bike (see page 66) and lay it flat on a
workbench. Remove the axle nuts or quick-release. Grab the axle with your
fingers and turn it back and forth (see photo). If there's any binding in the
bearings, the cone adjustment is too tight. If binding is not a problem, check
for looseness. Try to move the axle back and forth while holding the hub
steady. If you feel any play, the adjustment is probably too loose.
A hub that is either too tight or too loose should be adjusted. Before
adjusting any hub, one set of cone and locknut must be locked in
place on the axle. On front hubs, this can be done on either side,
while on rear hubs, it should be done on the right (drive) side of the hub. If
you're not sure if the locknut and cone are properly secured on a rear hub,
don't chance it. The process to check this adjustment is a little involved, but it
will save you the frustration of an adjustment that won't keep.
First, you must remove the cassette (see page 140) or the freewheel, otherwise, you won't be able to expose the right side cone and locknut. Now,
remove the left-side locknut, lockwasher, spacers (if there are any) and cone,
and push the axle just far enough to the right to expose the right-side cone
(be careful not to disturb the bearings – if you dislodge any, just poke them
back into place in the race).
HUBS
3
93
When the axle can be pushed to the right, hold the cone with a
spanner, grip the right locknut with another spanner and tighten the
two against each other to secure them in place on the axle (see photo).
Push the axle back into the hub and screw on the left-side cone by hand until
it rests against the bearings. Then add the spacers, lockwasher and locknut,
and snug the pieces in place by turning the cone anticlockwise while turning
the locknut clockwise with the spanners. Twirl the axle between your fingers to
check the adjustment. If it binds, the adjustment is too tight. Loosen
it slightly by holding the right-side locknut with a spanner and the left-side
cone with a cone spanner (see photo 4). With the tools on either side of the
hub, you should be able to back off the left-side cone slightly to fine-tune
the adjustment.
4
If the hub is too loose, hold the right-side locknut with a spanner
while turning the left cone clockwise until the play disappears. Still
holding the right locknut with the spanner, snug the left locknut
against the left cone. Secure the left side by placing spanners on the cone
and locknut and tightening them against each other. It may take a few tries
to get a perfect adjustment, but with practice it'll become simple. If it's difficult
to make a good adjustment, it may be a sign that the hub is damaged or just
full of dirt and needs to be overhauled and inspected for wear.
Before you make the final adjustment to your hub, there are a few points
you should note. If you have bolt-on axles, there should be no play in the
adjustment prior to tightening the wheel in the frame. If you have quickrelease axles, you must make allowance for the pressure of the skewer.
The adjustment of the cones will initially need to be a little loose because
when the quick-release skewer closes and compresses the axle, it makes
the adjustment slightly tighter. So there must be a little play in the axle
when it's wiggled.
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ILLUSTRATED BICYCLE MAINTENANCE
Cone-and-Locknut Type
Hub Overhaul
1
If your hub is equipped with a quick-release mechanism, thread the
the
adjusting nut off the end of the quick-release skewer and pull th
skewer out of the axle. Be careful not to lose the cone-shaped spring;
put it back on the skewer and partially thread on the nut so these parts won't
get lost. If you have an ordinary nutted axle, remove at least one of the nuts
in order to remove the axle from the hub. Fit a correctly sized cone spanner
onto the axle cone and another on the locknut (this must be done on the left
side of cassette-type rear hubs). Turn the cone clockwise and the locknut anti:lockwise to separate the two. For overhauling a freewheel rear hub, remove
.he freewheel as well.
. 11$111101PINW
Remove the locknut, spacers and cone from the axle, keeping them in
order. The axle will now slide out the other side. If you're careful about
how you do this, grease in the hub may hold the bearings in place.
iold the wheel horizontally over a rag while removing the axle from the top
o ensure that bearings don't bounce across your room if they to fall out.
eave the cone and locknut on the other end of the axle in place to simplify
oub reassembly. This way, you'll be sure to end up with the proper amount
of axle on each side of your hub.
3
Remove the bearings from the cups and set them aside. You won't be
reusing them, but once they're cleaned, they serve as a good initial
indicator of the condition of the hub's bearing cups and give you a
reference of the correct number and size of replacement bearings you should
purchase. Spray a light solvent or degreaser into the cups to break down the
grease and then wipe them clean with a rag. Rinse the cups with alcohol and
let them air-dry. Visually inspect the cups for pits, cracks or irregular wear.
Pitted or otherwise compromised cups on inexpensive hubs may be your cue
to replace the hubs or wheels altogether. Some higher-quality hubs may be
salvageable with the installation of new, replacement cups. Check with your
local shop about the possibility of this solution.
HUBS
4
95
If there is a significant amount of dirt contamination inside the hub, it
may be easiest to pry the dust seals out of the shell. These seals are
generally delicate, so proceed carefully. Gently pry at the cover from
several angles using a flat screwdriver. Once the covers are out, clean and
inspect the cups and covers as described above.
5
If you have a Shimano freehub body that requires replacement, this
is the time to do it. Insert a 10 mm hex key inside the freehub body
and turn it anticlockwise to remove the hollow retaining bolt. The
retaining bolt may be very tight. Clamping your hex key in a bench vice and
using the wheel for leverage can ease removal.
Fit a new freehub body on the hubshell's spline. Clean and grease the threads
of the retaining bolt and reinstall it into the freehub body and hubshell.
11111■11M1010
6
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Clean the axle and roll it on a level surface to see if it wobbles. If it
does, that indicates that it is bent and needs to be replaced. Take the
axle to the bike shop to get the proper replacement.
If the cones are excessively worn and need to be replaced, you must remove
the one remaining on the axle. Before loosening the locknut, measure and
record the position of the cone on the axle so that the new one can be
threaded to the same location.
If all is well, use your cone spanners to ensure that the cone and locknut are
tight against one another.
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ILLUSTRATED BICYCLE MAINTENANCE
Grease the axle well. If both cones came off the axle, put one of them
back on and carefully thread it down to its proper position. Replace
the lockwasher and the locknut, and lock the nut against the cone as
explained in Step 6.
When you have all the replacement parts you need, reassemble the
hub. Fit the dustcaps back on the hub shell, taking care to seat them
properly so the cones can be correctly adjusted. Some metal dustcaps
fit so loosely they won't stay in place. An easy fix is to gently grip the edge
with the jaws of some needlenose pliers and pull it out very slightly. Repeat at
two other spots so that there are three points, each about one-third of the way
around the dustcap, that are slightly pulled out. The dustcap will be a tight fit
and will stay put.
Apply a thick bead of fresh grease into each of the bearing cups. Insert the
correct number (usually 9 per side on rear hubs and 10 per side on fronts)
and type of new ball bearings into side of the hub (drive side on freehubs).
The grease will hold the bearings in place for the moment. Slide the axle
partway into the hub to secure the bearings in the cup. Insert the new bearings into the other cup. Once they are all in place, slide the axle the rest of
the way through the hub.
HUBS
9
97
Thread the cone onto the axle until it makes contact with the bearings.
Lift the wheel up into a vertical position to check the bearing adjustment. Twirl the axle a bit to make sure the bearings are properly
seated, then adjust the cone until there's no tightness or play in the hub.
10
When the adjustment is right, slide on the spacers in the correct
order, followed by the locknut. Hold the adjustable cone still with
a cone spanner while you tighten the locknut against it. Slide the
quick-release skewer back through the axle and thread on its nut. If you have a
nutted axle, replace the axle nuts. Remount the wheel on the bike.
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ILLUSTRATED BICYCLE MAINTENANCE
Overhauling and Adjusting a
Campagnolo Hub Equipped
with an Oversize Axle
1
Newer Campagnolo hubs use a very large-diameter axle for stiffness and
weight savings. Along with this new axle, Campagnolo has devised a
simple new method for overhauling and adjusting their hubs. Front and
ear hubs follow the same steps, with the difference that the freehub body on the
ear hub will stay in place on the axle through all the steps. Campagnolo's new
reehub bodies use cartridge bearings and don't require regular maintenance.
remove the quick-release skewer and set it aside. The left side of the hub has
I pinch bolt on the adjusting ring. Loosen this with a 2.5 mm hex key.
2
Remove the left-side axle cap using a pair of 5 mm hex keys, one in
each axle end. Turn them anticlockwise and the axle cap will thread
right out. Be sure to keep track of the thin washer between the axle
ap and axle – don't lose it.
3
The adjusting ring will now thread off of the axle. It may require
a wrench to start.
HUBS
4
99
Lightly tap the end of the axle with a plastic or rubber hammer to free
the axle from the collet that holds the cone in place. The axle is made
of aluminium, so under no circumstances should you use a metal
hammer for this step. In the absence of a plastic hammer, use the handle of a
screwdriver or a block of wood between the hammer's head and the end of the
axle. Pull the axle out from the right side and remove the collet and axle from
the left. On rear hubs, you may need to slowly rotate the freehub body anticlockwise as you pull it out to let the ratchet pawls snap free.
5
Carefully pry the white seals out of the hub using a pick or small
flat screwdriver. Be gentle: too much force could deform the seals,
rendering them less effective or even unusable. Remove the bearings
and retainers form the hubshell. Pay close attention to the orientation of the
retainers in the hub; you'll need to reinstall them facing the same way. You
can discard the retainers if you have a complete, new set. If not, pop the old
bearings out, clean the retainers thoroughly with degreaser, then with alcohol
and press new bearings into place.
7411■11111110k,
6
Clean everything. Do this first with degreaser and a rag. After
degreasing, use alcohol and a fresh clean rag or paper towel to
rinse everything spotless. Lay all the cleaned parts out on a clean
rag. Apply a bead of fresh grease covering both cups in the hubshell, and
then put the bearing retainers in place, with retainers facing in and exposed
bearings facing out.
1 00
ILLUSTRATED BICYCLE MAINTENANCE
7
Press the seals back over the bearing retainers in their cups. They
should pop easily into place with just a little pressure from your
thumbs. Slide the axle in from the right, then slip on the left-side cone
and collet. On rear hubs, you may need to slowly rotate the freehub body anticlockwise to allow the ratchet pawls to slip into place. Thread the adjusting ring
into position, but don't tighten it yet. Using your two 5 mm hex keys, tighten the
axle cap and washer back onto the axle end.
8
Bearing adjustment on this system is independent of quick-release
tension, unlike most other quick-release hubs. Thread the adjusting
ring down by hand until you feel the cone make contact with the
bearings. Use an adjustable spanner to turn the adjusting ring down just a
fraction of a turn to properly preload the bearings. Turn and wiggle the axle
with your fingers. It should spin smoothly and not bind, and have no looseness
li ke you want with conventional quick-release hubs. If your adjustment is too
tight, you will need to back the adjusting ring off and tap the axle end with a
plastic hammer to release the collet's grip on the axle. Then start your adjustment again. When the adjustment feels right, tighten the pinch bolt on the
adjusting ring.
AIM
9
Well done. Put the quick-release skewer back through the axle, and
you're ready to roll. Don't forget to properly orient the volute springs
on the skewer – with the narrow end towards the hub.
HUBS 101
Lu bricating Sealed Cartridge
Bearings
1
On a conventional cup-and-cone loose-ball-bearing hub, when the
cone is removed, a ring of steel ball bearings is visible inside the hub.
If, after you've removed the cone, you see a flat, black plastic seal (see
photo), your hub has cartridge bearings. Such sealed bearings generally hold
up quite well, which is why they are common on upper-end mountain bikes.
Some cartridge bearing hubs are not user-serviceable and have to be referred
back to the manufacturer or to bicycle shops with special tools for maintenance.
These hubs usually don't have a place to attach a spanner to the axle. If you
suspect you have such hubs, consult your bicycle dealer before attempting to
service them.
2
If your cartridge bearing hubs can be user-serviced, it's not a complicated procedure. Although the seal protects the bearings, it also allows
moisture to be trapped inside, so it's important to periodically regrease
the bearings. To service this type of hub, first wipe off any dirt that has accumulated on the seal. Gently slide the tip of a sharp knife or craft knife under the
edge of the plastic seal and pry the seal off the bearing cartridge (see photo).
Be careful: don't bend the seal.
3
11111■1■11M
Once you've removed the seal, you'll see the bearings beneath.
Charge them with fresh grease by squeezing in enough to cover all the
balls (see photo). Then simply press the seal back in place with your
fingers until you feel it seat in the cartridge. Repeat for the other bearing, and
reassemble the axle. Some hubs with serviceable cartridge-sealed bearings
employ clever axle designs that seem impossible to disassemble. In some cases
they are; in others they only seem so. It may take some detective work to find
the secret, but if you can figure out how to get the hub apart, regreasing the
bearings is easy. If it's a particularly challenging design, contact a shop or the
manufacturer for instructions or advice or simply let an expert service the hub.
CHAPTER 6
C ra n ksets
The crankset, like most parts of the bicycle, is designed first
and foremost to do its job in the most efficient manner possible — a textbook case of form following function. As such.
what is one of the bicycle's largest components is also one 01
the most recognizable. The designs differ slightly, but all
cranksets do the same job: they serve as the point where
human power becomes mechanical motion by taking leg
power from the pedals and transferring it to the chain and
ultimately to the rear wheel. The crankset also must support
the weight of the rider when standing — or landing — so it
needs to be very strong.
Most cranksets consist of a right and left crankarm, o
bottom bracket assembly (this includes the spindle, cups and
bearings held inside the frame) and one or more chainrings.
The right crankarm is the one that has the chainrings
attached to it. These chainrings attach to arms built into the
crankarm or a plate that attaches to the arm. This part of the
crankarm is the spider.
The spider's arms radiate outward from the base of the
right crankarm. Some cranksets integrate the spider with the
chainrings, while others make the spider part of the right
crankarm, with the chainrings as separate pieces. The ability
to separate the chainrings from the spider makes them easy to
replace when worn or damaged.
There are three general kinds of cranksets: one-piece
cranksets, cottered cranksets and cotterless cranksets. Onepiece cranksets, sometimes called Ashtabula cranksets, are
found primarily on children's bicycles and inexpensive adult
bicycles. These cranksets integrate the bottom bracket spindle
and the crankarms into one piece. One-piece cranksets are
generally made of steel, which makes them very durable, but
also quite heavy. All it takes to service this type of crankset is
a pair of water-pump pliers that are large enough to grab the
nut on the left side. Keep in mind, though, that this nut and
the cone beneath it (it's sometimes covered by a washer),
which is used to adjust the bottom bracket, are reverse-thread.
Turn to the left (anticlockwise) to tighten and to the right
(clockwise) to loosen.
Cottered cranksets use two separate crankarms that mount
onto a spindle. These cranksets are held on the spindle by
means of cotters, tapered metal pins inserted through holes ir
the crankarm that are lined up with grooves on the ends of the
spindle. Generally, either a hammer or a special press is used tc
seat the cotters firmly, and nuts fastened to their ends hole
them in place. Most cottered cranksets are steel, though some
have aluminium alloy chainrings.
Cotterless cranksets are the most popular cranksets for use
on high-quality bikes. Most cotterless crankarms have square
tapered holes that fit onto the end of a spindle, which is alsc
square and tapered on the ends. In recent years, new designs
for fitting crankarms to spindles have emerged that employ o
larger, splined hole and spindle. All cotterless crankarms are
held in place with either a nut or a bolt (see illustration
below), depending on whether the spindle ends have
threaded studs on their tips or are hollowed out and threaded
on the inside. Most cotterless cranksets and chainrings are
made of aluminium and come in a multitude of styles and
offer a wide selection of crankarm lengths, chainring sizes and
bottom brackets.
The Bottom Bracket
The bottom bracket consists of the spindle (which may have
cone-shaped bearing races near each end), two cups and two
sets of bearings that are mounted in the bicycle frame and
support the crankarms. Currently, the most common type of
bottom bracket on quality bikes is designed as a one-piece
cartridge that requires little, if any, service.
The part of the bicycle frame in which the bottom bracket
is installed is the bottom bracket shell. The bottom bracket is
held in the shell by cups that thread in.These, along with the
bearings, support the spindle and the crankarms attached to it
and allow them to spin.
THREADED SQUARE-TAPER SPINDLE
HOLLOW-AXLE SQUARE-TAPER SPINDLE
HOLLOWED AXLE END
On this square-taper spindle design,
the hollow axle ends are threaded to
take a bolt, which clamps on the cranks.
■ BOLT
On this older square-taper spindle
design, a nut threads over the ends of
the spindle to hold the cranks in place.
THREADED STUD
NUT
1 04
ILLUSTRATED BICYCLE MAINTENANCE
The Chainrina Ganc
CRANKSETS 105
AXLE? SPINDLE? WHICH IS IT?
Two terms exist for seemingly similar components - axles and
spindles. It's easy to confuse the two, but there is a difference
- and it has to do with how the part does or doesn't move.
Simply put, an axle remains stationary while something rotates
around it - like the axle of a wheel - and a spindle revolves
inside a stationary bracket - like the spindle of a crankset.
The main function of the bottom bracket is to spin. However. while the spindle spins, it must also carry the torsional
and lateral loads produced when the bicycle is pedalled. To
minimize power losses and wear, the bottom bracket bearing
adjustment must be properly maintained. A bottom bracket
spindle should spin smoothly, without binding or looseness,
on bearings that are properly protected. Grease is used not
only to lubricate the bearings but also to protect them from
both dirt contamination and moisture that can cause rust.
Sealed-bearing systems are the latest word in bottom
brackets. Shimano currently produces only this type of bottom
bracket, and most of Campagnolo's are also sealed. These units
require little or no service because the bearings are protected
with seals that prevent the grease and the bearings from
aiming contaminated with grit. If you have a good-quality
manufactured after 1992, it probably has a sealed bottom
7acket, which will require little service. In fact, most of these
bottom brackets are designed to be replaced if they wear out or
fail. Fortunately, they hold up nicely and aren't expensive when
it's time to replace them. The bearing is preadjusted and prelubricated at the factory, so it's impossible to damage by maladjustment, and because it's sealed, it's unnecessary to lubricate it.
Some sealed-bearing bottom brackets can be serviced, but
they may require special (and sometimes expensive) tools. Some
units, however, can be serviced with standard tools. Because each
a unique design, consult your owner's manual to find out
how to service the unit. As a general rule, if you can access the
bearings, it's usually possible to add grease, which in many cases
is all the service that is required to keep these sealed units operating smoothly.
More Is Better
Two major new developments made in recent years have all
but taken over the market of high-performance cranksets and
bottom brackets — spline interfaces and external bottom
brackets. Tried and true, square spindles have been around for
decades, and they are entirely adequate. They make contact
with each crankarm at four points and maintain their grip by
slightly stretching the aluminium crankarm over the tapered
spindle. The endless search for greater performance, more
strength and less weight, however, knows no bounds. Progression in the realm of freeride mountain biking, too, has strained
the capabilities of the trusty square spindle.
There are three spline interface designs that are common on
the market today. Shimano developed both the OctalinkV-1 and
OctalinkV-2; the third design, ISIS (International Spline Interface System) was born of a cooperative effort between Chris
King Components, RaceFace and Truvativ. The Octalink V-1,
OctalinkV-2 and ISIS are in no way cross-compatible, so be sure
of what you have before spending your money.
There are two key benefits to the design of these spline-fit
bottom brackets. First, by using several splines rather than a
square as the interface, the contact area between crankarm and
spindle is increased, reducing the risk of mashing the relatively
soft aluminium of the crankarm on the steel of the spindle under
heavy torque or impact (which ultimately results in a poor fit
between spindle and crankarm and requires replacement of the
PHIL WOOD SQUARE TAPER
BOTTOM BRACKET
SHIMANO OCTALINK
BOTTOM BRACKET
RACE FACE SRX ISIS
BOTTOM BRACKET
SHIMANO ULTEGRA
BOTTOM BRACKET
Cotterless crank bottom brackets now come in several different
configurations. When replacing crankarms or bottom brackets, be
sure of which system you're using.
1 06
ILLUSTRATED BICYCLE MAINTENANCE
arm). The second benefit is the larger diameter of the spindle.
This makes it possible to manufacture a hollow spindle with thin
walls, saving weight while maintaining the same level of strength.
Or, the spindle can be made thick, yielding more strength than a
traditional spindle ever could.
The Price
Since the diameter of the bottom bracket shell remained the
same and the spindle got larger, it became necessary to use
smaller ball bearings. Smaller ball bearings need to rotate
more times per revolution of the spindle and thus, they wear
out more quickly. Don't throw out your spline-fit cranksets
just yet, though. These bottom brackets still last many thousands of miles and the benefits to most riders in terms of
strength, rigidity and weight savings far outweigh the shortcoming of marginally reduced bearing life.
The Next Level
Not ones to rest, both Shimano and RaceFace have raised the
bar again with new cranksets that address the issue of how to
fit a large spindle and full X-inch ball bearings without
enlarging the frame's bottom bracket shell. In the sort of
move that is obvious only after someone else has thought of
it, they figured out that putting the bearing cups to the outside of the bottom bracket shell would give them all the space
they needed and even produced another benefit — a wider
bearing stance that makes the drivetrain even a little bit stiffer.
These new outboard bottom brackets require specific
cranksets, but what cranksets they are! The cranksets are built
with a spindle that is permanently or semi-permanently
attached to one of the two crankarms. With one arm and the
spindle making up one piece and the other arm as the second
piece, these cranksets have come to be known, logically, as
two-piece cranksets. On top of the leaps made in the categories of weight, strength and service life, installation has
become incredibly simple and straightforward, as well.
Both manufacturers have a slightly different approach to
installation. Shimano's spindle is permanently fixed to the
BOTTOM BRACKET THREADING
Bracket Type
Threading
English
1.37" x 24 tpi*
French
35 mm x 1.0 mm
Italian
36 mm x 24 tpi*
* threads per inch
Note: All left-side cups (nondrive side) are turned clockwise to
tighten/install. English right side cups are reverse-threaded (turned
anticlockwise to tighten/install). French and Italian right-side cups
are turned clockwise to tighten/install.
right crankarm, and the left arm attaches by means of a preload cap with a pair of pinch bolts to hold the arm firmly in
place. Conversely, RaceFace semi-permanently fits the spindle
to the left arm (meaning the spindle or left arm can still be
replaced individually if the need ever arises) and affixes the
right arm in the same manner that their ISIS splined spindles
and crankarms are mated. Oddly enough, though, these two
fiercely competitive manufacturers use a common spindle
diameter and bearing stance, making it possible to use a RaceFace crankset with a Shimano bottom bracket, and vice versa.
Identifying the Bottom Bracket Type
Cup-and-cone-style bottom brackets, unlike sealed models,
require regular maintenance. To determine if your frame has
this bottom bracket type, look for a notched and possibly
knurled lockring on the left side (the side without the chainrings). Also look at the cup faces. Modern sealed-cartridgestyle bottom brackets (see photo on page 105) employ cups
that are splined inside to accept the installation and removal
tool. Other sealed bottom brackets have notched rings on both
the right and left sides. If you see the notched ring only on the
left side and notice that the cup faces are flat, your frame probably has the older cup-and-cone-style bottom bracket.
To function properly, this type of bottom bracket requires
periodic maintenance. How often maintenance is performed
depends on the number of miles ridden, the environment and
the kind of bottom bracket. Road bicycles ridden only on
sunny weekends at distances of approximately 50 kilometres
(30 miles or less) may require a bottom bracket overhaul
every 2 or 3 years. Bicycles that are used every day, regardless
of the weather, should be overhauled at least once a year.
Mountain bikes ridden in the muck may require it twice a
year or more. Preventive maintenance could save you the cost
of a new bottom bracket.
Changing Cranks
To change the crankset, consider these factors.
What kind of bottom bracket do you have? If your frame
has an oversize bottom bracket shell used for one-piece
cranksets you can use only one-piece cranksets unless you
buy a conversion bottom bracket assembly. However, these
conversion kits are hard to find and are intended primarily for
BMX (bicycle motocross) bicycles, and you may have trouble
fitting a double- or triple-chainring crankset to them since
they were intended for single-chainring use.
Cottered and cotterless bottom brackets, on the other hand,
thread into the bottom bracket shell the same way. So if you
have a bike with a cottered crankset, you can change to a cotterless unit, as long as you change everything.That is to say, you
can't use a spindle from a cottered bottom bracket assembly
with a set of cotterless crankarms. The spindle and the
crankarms won't match.
CRANKSETS 107
The major consideration when changing bottom bracket
assemblies is the threading of the bottom bracket shell. Most
bottom brackets come in English, French or Italian threadings.
You must get the correct one for your frame; they are not interchangeable.To complicate matters, the frame's origin isn't always
a true indicator of its type of bottom bracket threads. But with
a set of calipers and a thread gauge, it's possible to measure the
cups. Check them against the table on page 106 to determine
the threading and type of bottom bracket needed. Otherwise,
take one of the cups or the entire bicycle to a bicycle shop to
find out what kind of threads it has.
Another factor to consider when replacing bottom
brackets is the width of the bottom bracket shell. The two
most common sizes are 68 mm and 70 mm. Some mountain
bikes have 73 nun bottom brackets. Most French- and English-thread bicycles have a bottom bracket width of 68 mm,
while 70 mm is standard for most bottom brackets equipped
with Italian threads. Sometimes the spindle is stamped with a
68 or 70 to tell you the bottom bracket width for which it
was designed, but the only way to be certain of the width of
your shell is to measure it. Use a small ruler to measure from
one side to the other. Don't include any part of the bottom
bracket — just measure the bottom bracket shell width.
Most cranksets have a bottom bracket that is designed
specifically for them. If you want to mix the crankset of one
manufacturer with the bottom bracket of another, check with
one of the manufacturers as to the compatibility of such a
match-up. Sometimes it works and sometimes it doesn't.
Most replacement cranksets are made of aluminium, which
makes them quiet, light, durable and trouble-free when
installed correctly. When purchasing a crankset, be sure to get
a model with interchangeable chainrings. Look for aluminium chainrings when possible. Some inexpensive
cranksets come with steel chainrings, but compared to aluminium, steel rings are heavy and very noisy when shifting.
The exceptions are on some mountain bike cranksets. On
these, you'll sometimes find steel used for the smallest chainring because an aluminium model could wear quickly.
Generally, the higher the price of the crankset, the higher
the quality. Inexpensive aluminium cranksets sometimes have
the right crankarm swaged on to the spider. A swaged fitting
is similar to a rivet; one piece of metal is bent in such a way
that it holds firmly to another piece of metal. A fitting of this
type can loosen with age. In better cranksets, the arm and the
spider are forged from a single piece of metal or bolted
together.
As you go up the price scale in cranksets, you find systems
made of lighter and stronger materials. The machining
processes get more precise, which translates into systems that
allow better and quieter shifts and chainrings that last longer.
Weigh the benefits against the costs to determine the level of
quality you are willing to pay for.
The most recent trend in performance cranksets is the two-piece design,
where one crankarm is permanently or semi-permanently attached to
a large-diameter, hollow spindle. The bottom bracket bearings for these
systems ride outside the bottom bracket shell, allowing for larger, more
durable bearings and increased drivetrain rigidity.
Also decide what chainring sizes to buy. Some cranksets
offer a wider range of possibilities than others. For more
information on an individual crankset's range, ask a shop that
sells the crankset or check the manufacturer's literature. For
advice on how to determine the chainring sizes that best suit
your riding ability and needs, consult Chapter 17.
One basic decision is whether you want a double- or a
triple-chainring set.The double is standard fare for road racers
and most road sport riders, but many people prefer the gearing
flexibility that is gained with a triple. Triples are standard on
mountain bikes, and they can add a low range of gears that are
well suited to loaded touring and steep climbs. If you don't
expect to do much of this type of riding, the third chainring
may be useless, so think carefully about your gearing requirements and decide accordingly. Just be sure that the crankset
you select accepts the chainring sizes you want.
There's also the matter of crankarm length. The standard
mountain bike length is 175 mm, and on road bikes it's 172.5
mm.While these are the most readily available and most commonly used, crankarms arc available in 2.5 mm increments,
from 165 nun to 185 nun. Crankarms are measured from the
centre of the pedal hole to the centre of the crankarm
dustcap, but the length is usually stamped on the back.
There are a few theories concerning crankarm length.
Most relate the length of the crankarm to the rider's leg
length. Longer arms aid uphill riding because they offer
greater leverage, but they're more difficult to spin, so they
li mit leg speed. For a long-legged rider this isn't a problem
because longer thigh muscles benefit from the added
crankarm length. For shorter riders, it can hinder effective
pedalling on the bike. Long crankarms may enhance the
climbing ability of such riders, but the rest of the time their
riding will suffer.
1 08
ILLUSTRATED BICYCLE MAINTENANCE
Ifyou're tall (over 180 cm [6 feet]), climb a lot and tend to push
big gears rather than spin, long crankarms are for you. Otherwise,
you should stick to 172.5 mm — or shorter, if you have short legs.
Interestingly, mountain bikes come stock with 175 mm
crankarms. This is because when riding off road, there's more
climbing and the speeds are slower. For most riders, this
length is perfect. Only riders under 150 cm/5 feet tall need
to consider swapping for shorter crankarms. Consider longer
arms only if you're 190 cm (6 feet 4 inches) or taller. Before
buying, make sure that you'll still have sufficient ground
clearance if you ride technical trails.
Overhauling a Crankset and Bottom Bracket
Special tools are needed for cotterless crankset and bottom
bracket overhauls, depending on the type of crankset and
bottom bracket. For all types, you'll need a crankbolt spanner
and crankarm extractor to remove the crankarms.
Most sealed-cartridge bottom brackets are removed and
installed with splined tools that fit inside the cups. Get the
model that matches your bottom bracket (usually Shimano or
Campagnolo). Cup-and-cone-style bottom brackets require a
lockring spanner, a pin tool for the adjustable cup and a
spanner for the fixed cup.
To overhaul cup-and-cone-style bottom brackets, use
medium-weight grease and purchase new ball bearings of the
appropriate number and size (usually 22 of the h-inch size).
The traditional method for removing cotters from a crankarm involves using
a hammer and punch. Support the crankarm with a wooden block or length
of pipe to transmit the force of the hammer blows directly to the cotter, or
the hammer blows may simply smash the cotter, essentially fusing it into the
crankarm and making it nearly impossible to remove.
Remove the pedals. If the crankset is grimy and you plan to
clean it with solvent, remove the pedals to prevent solvent
from getting inside the pedal bearings. First, shift the chain
onto the large chainring to minimize the chances of getting
cut by the teeth while removing the pedals.
Pedal removal usually requires a 15 mm pedal spanner.
Some newer clipless designs from Time, Crank Brothers, Shimano and others will need a long 6 mm or 8 mm hex key,
while older French pedals fitted into French-threaded
crankarms require a 16 mm open-end spanner. The right
pedal, the one on the side with the chain and sprockets, has a
right-hand thread and threads out anticlockwise. The left
pedal has a left-hand thread and threads out clockwise.
To remove either pedal, rotate the crankarm until the pedal
is at the front of the bike. Fit the spanner on the pedal so that
it runs back alongside the crankarm, then push down. Keep
the bike from moving and the wheels will provide the
resistance needed to keep the crankarms from turning while
loosening the pedals.
Once the pedals are off, remove the crankarms from the
bottom bracket spindle. Remove the left crankarm first.
Remove the cottered crankarms often found on old bikes.
If you have an old-fashioned cottered crank, remove the arms
by loosening the cotter nuts and forcing out the cotters. Use
a spanner to loosen the nuts, a hammer and punch to drive
out the cotters, and a block of wood to support the crankarms
while you're pounding on them. Commercial cotter-pin
presses are available, but they cost more than individual bike
owners generally want to pay. Some people have created
homemade presses with such things as locking pliers and
heavy-duty C-clamps, but the hammer approach is the one
most commonly used. Whatever method you use, plan on
buying new cotters because the removal process usually damages the originals.
Remove the cotterless crankarms. A specialized tool is
needed to remove cotterless crankarms, though the process is
much easier than driving out cotter pins. Don't try to remove
crankarms by any method other than using the tool made for
the job. There are universal crankarm removal tools on the
market that work, but the wisest choice is to use the tool
made by the manufacturer of the crankset because it will be
the one most certain to fit. Some crankset manufacturers
make a tool that has a bolt spanner at one end, a crankarm
extractor at the other and spanner flats in the middle for gripping and turning the tool.
There are three common ways that crankarms are attached.
Most new bikes have hex key bolts securing the crankarms.
Removal is simple: just turn the bolts anticlockwise with the
appropriate hex key. On other bikes, there may be dustcaps
covering the crankarm bolts. Remove them to get at the bolts.
1b4
There are also cranksets equipped with one-step removal systems.
In these systems, the dustcap is left in place during the
crankarm removal process.A hole in the dustcap allows you to
insert a hex key into the head of the bolt. As you unscrew the
bolt, it pushes against the back of the dustcap, forcing the arm
off the end of the spindle (so you don't need a crankarm
removal tool, just the hex key).
Dustcaps that cover crankbolts are simply protecting the
Ithreads inside the crankarms, into which the crankarm
(
extractor will fit. Such a dustcap has either a narrow slit in it or
a hole that is shaped to receive a hex key. If it's the latter,
remove the dustcap with the appropriate key. If it's the former,
'
use a wide, flat-blade screwdriver or a coin. If the slit is on the
dustcap edge, pry the dustcap off. If the slit is centred, unscrew
(the dustcap. Don't damage the dustcap.
I Once the dustcap is off, remove the fastener that's holding
the crankarm on the spindle. Square-taper bottom bracket
(spindles come in two types (see the illustration on page 103).
One type has a threaded hole in each end, and bolts, aided by
washers, hold the crankarms in place. The other type has a
threaded stud at each end and serrated nuts that need no
washers to hold the crankarms in place. Use a crankarm bolt
spanner or a thin-wall socket to remove the crankarm bolt or
nut. Be sure to remove the washers, too (if there are any).
Before you thread the crankarm extractor into the
crankarm, make sure that the centre section of the extractor
is backed all the way out. Also double-check that the washer
is not inside the crankarm, because it will prevent removal.
Thread the extractor in until the threads of the tool have
gone all the way into the threads of the crankarm.
Turn the centre section of the tool clockwise (use a spanner
if necessary) until it pushes against the spindle. Continue
turning to force the crankarm off the end of the spindle.
Check the bottom bracket and clean the chainrings.
Once the crankarms are removed, grab the end of the spindle
and turn and wiggle it to check the adjustment. Is there play?
Does it spin smoothly, or does it bind? Does it turn with a
hydraulic-like resistance? How much dirt is clinging to the
area around the spindle? These are indicators of problems that
may mean you should replace the cartridge (if it's a sealedcartridge bottom bracket), or that you should overhaul the
unit (if it's a cone-and-cup type).
With the crankarms off the bike, wipe the dirt from
around the bottom bracket area of the frame (be careful not
to push dirt into the bottom bracket bearings, unless you're
replacing or overhauling them). This is also a good time to
disassemble the right crankarm, remove the chainrings and
clean them. Do this with a 5 mm hex key. If a bolt turns but
won't loosen, hold the back of the bolt with a chainring nut
spanner, a special tool that fits in the groove on the back. (Try
a wide-blade screwdriver if you don't have the tool.) Grease
the bolts before reassembly and tighten them securely. Otherwise, your crankset may drive you bonkers with annoying
clicking sounds when you're out on the trail.
If the bottom bracket is a sealed-cartridge model, the
spindle should turn with a hydraulic resistance. A sealed
bottom bracket is shot when the spindle spins effortlessly and
feels and sounds dry Also, look for signs of rust near the
spindle, which indicate that water has penetrated the seals and
contaminated the bearings. Oddly enough, it's possible to ride
on a wasted sealed-cartridge bottom bracket, but expect some
crunching noises and don't count on it lasting too long. The
bearings may disintegrate and jam the spindle.
Sealed-bearing bottom brackets are available in a wide
price range, so it's always best to simply buy and install a new
one if yours is worn out. Installation is easy, just be sure to
purchase the correct replacement bottom bracket. The new
one must match the length of the old one. The folks at the
bike shop can select the right one if you take the old one in.
If you're checking a cup-and-cone-style bottom bracket,
feel the spindle for roughness and play. If it turns smoothly
with a slight hydraulic resistance and no play, it doesn't need
to be overhauled. Always check the tightness of the fixed cup
(on the left side) and lockring with tools.
The fixed cup is tricky It probably tightens by turning to
the left, but if that loosens it, turn it to the right. Get it as tight
as possible. (If the loosening repeats, back out the fixed cup so
that several threads show, apply thread adhesive and tighten.)
Then snug the lockring before reinstalling the crankarms.
Installing Cartridge-Style Bottom Brackets
Before installing a new cartridge-style bottom bracket, you'll
need to remove the old one. It might be as easy as turning the
cartridge out with the splined removal tool.Turn the left-side
cup first, anticlockwise, until it comes out of the frame. Then
turn the right side clockwise to remove the cartridge.
If the cups won't turn, don't force them initially, especially
if they're made of plastic. Instead, apply a penetrating solvent
to the cup edges and tap the bottom bracket shell with a
hammer to vibrate it, which works the solvent into the
threads. Wait a while and try to turn the cups again. Repeat
this procedure until the cups unscrew, or take the bike to a
shop for professional help.
Cartridge-sealed bottom brackets come packed with
grease and adjusted from the factory. Before installing the new
cartridge, turn the spindle by hand to feel how it turns — how
the factory adjustment feels. When it's installed, the spindle
should turn approximately as easily as this.
Cartridge bottom brackets usually have one cup pre-installed
on the drive side of the cartridge. If the bottom bracket is
being installed in a titanium frame, coat the threads with an
anti-seize compound. Finish Line Ti-Prep is a titaniumspecific anti-seize available at most bike shops, but if you can't
110
ILLUSTRATED BICYCLE MAINTENANCE
find it, a copper-based anti-seize from a hardware store is
close to the same thing. This will prevent chronic clicking
noises from the bottom bracket area and inhibit galvanic corrosion that could freeze the bottom bracket into the shell.
Another solution is to wrap plumber's Teflon tape around the
threads before installing the cartridge and cup. (Grease is usually adequate for steel and aluminium frames.)
Start threading the cartridge into the drive side of the
frame by hand-turning it anticlockwise. Be careful not to
cross-thread it. When it gets tough to turn, install the splined
tool and continue turning until the cup is snug and fully
screwed into the frame (it'll only go so far because of the
built-in lip on the cup's edge).
Install the other cup (be careful not to cross-thread it),
turning it clockwise with the splined tool. Check how things
are going by turning the spindle by hand. If it's a lot tighter
than it was before installation, it's likely the cup is going in
crooked. Remove it and start it again, making sure it's straight.
Turn the cup until it bottoms against the cartridge. When the
cup is secure, check the installation by putting the splined tool
on the drive side again and making sure it's tight, then
double-checking the tightness of the left-side cup. Finally,
grab the spindle and turn it. It should feel smooth, like it did
before installation. If not, try again.
There are many different sealed-bearing bottom bracket
designs today. The preceding directions apply to common
types. If yours seems different, follow the manufacturer's
installation instructions. If you don't have them, get them
from the dealer who sold you the bottom bracket, contact the
manufacturer, or check its Web site.
Overhauling Cup-and-Cone Models
To disassemble cup-and-cone-style bottom brackets, remove
the lockring (on the left side) with a lockring spanner. Some
spanners are unique to a particular brand of bottom bracket,
while others, such as hook spanners and plier-type spanners,
are more universal. Once again, tools made to match with a
particular brand of component are generally the surest fitting,
but not all manufacturers have such tools.You may have to use
the universal kind. If you don't have a lockring spanner, a
hammer and punch, used with care, can be used to drive the
lockring off. Some lockrings have peculiar notch spacings and
may require a hammer and punch since even the universal
tools won't grip the part adequately.
Remove the lockring by turning it anticlockwise. W rk
cautiously — the threads of the ring and the cup are pro e to
producing metal shards that can jab your fingers.
Turn the adjustable cup (what the lockring was holding in
place) anticlockwise to remove it. Usually a special spanner is
needed for this also. Many of the better bottom brackets
match a pin spanner with a series of six pinholes
in the adjustable cup. Some cups have notches, and a few have
a hex fitting. Here again, some companies make dedicated
spanners for their adjusting cups, and these will ensure the best
fit, but universal pin-and-notch spanners are also available.
When removing the adjustable cup, be careful in case the
bearings are not in a retainer. Place a rag or a piece of paper
under the bottom bracket to catch any bearings that may drop
out. Once the adjustable cup is out, remove the spindle, bearings and dust sleeve. Not all bottom brackets have the latter,
which is a plastic sleeve that prevents dirt and debris in the
frame tubes from contaminating the bearings.
For the time being, leave the fixed cup in the frame. Clean
and examine all the bottom bracket components that you
removed, as well as the bottom bracket shell and the fixed
cup. Use solvent and either a rag or a small brush to remove
any contaminants and as much grease as possible.
Look at the adjustable cup race for any pitting or excessive
wear on the scored line around the surface of the race. This is
the bearing path. Carefully check the spindle at the shoulders
for the wear line and examine it closely. Inspect the fixed cup
also, possibly with a flashlight. Look at the ball bearings.
Check to make sure that none have cracked or broken. See if
the retainer (the metal or plastic ring that holds the bearings)
is intact. If either a bearing or the retainer is damaged, make
sure that no broken parts remain inside the frame to contaminate the bottom bracket after reassembly.
If any of the components are heavily worn or damaged,
replace them.They'll ruin the bottom bracket adjustment and
cause additional wear to the other components.
Replace all the bearings, even if they don't appear worn.
Good bearings are inexpensive and will make adjusting the
bottom bracket easier.
If the fixed cup is worn and needs to be removed, it's best
to have the task performed at a bicycle shop that has a special
fixed cup tool. In sonic cases, it's possible to lock the fixed cup
in a vice and spin the frame off it. This method will work if
the flats of the fixed cup are large enough to grab. However,
proceed very carefully — you--could-damage the cup or your
frame.The fixed cup-may be locked down very tightly to keep
it from worjcing loose. Most home mechanics cannot get
enough leverage to remove this part. If the special fixed cup
tool isz needed to remove your fixed cup, you will also need it
p)--lc<ck the cup or its replacement back into your frame.
If you must remove the fixed cup, remember that Englishthread bicycles (found on most bicycles) use left-hand threads
on the fixed cup, meaning that the fixed cup spins out clockwise. All others, except for some rare Swiss threads, unscrew
anticlockwise. When installing a fixed cup in a steel frame,
apply thread adhesive to ensure that it stays tight.
Tapping and facing cup-and-cone bottom brackets. If you
have removed both cups from the cup-and-cone-style bottom
bracket, you may want to have the bottom bracket shell
Vt 11.1111 1 11
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tridge bottom brackets). Tapping cleans and cuts the threads
to theproper clmens;on_ rnaLng threading in die cups easier.
It also makes both sets of threads concentric, that is, cut on
the same axis, which allows a finer bearing adjustment than is
otherwise possible. The facing tool shaves the bottom bracket
shell's outer edges so the lockring and the fixed cup seat are
parallel to each other and perpendicular to the axis of the
spindle.
Custom framebuilders tap and face bottom brackets as a
matter of course, but many fine stock frames have never been
faced. If you have such a frame, you may want to have a
bicycle shop tap and face it for you. It is a one-time expense
that will provide you with years of easier and more precise
bottom bracket adjustments. It's usually needed for a cartridge-sealed bottom bracket only when the frame threads are
so poorly manufactured that the cartridge can't be threaded
in (this is a rare occurrence).
Installing Cup-and-Cone Bottom Brackets
Now that you have removed, cleaned and replaced any worn
parts of the bottom bracket, reinstall everything.
If you removed the fixed cup, grease both its threads and
those in the bottom bracket shell before threading the cup
back in. Be sure that the fixed cup is locked down very
tightly, preferably using a tool designed for fixed cups. If
you've had problems with this cup repeatedly loosening,
don't grease it or the frame. Instead, apply thread adhesive
before installing and tightening it.
Apply a liberal amount of medium-weight grease to the
fixed cup's bearing race. If medium-weight grease is unavailable, lightweight grease is preferable to heavy. To apply the
grease, reach through the bottom bracket. Be careful not to let
any dirt or metal from the bottom bracket contaminate the
grease. Once the race is greased, install the bearings. If the
bearings are in a retainer, pack the retainer with grease and
insert it into the cup. If the bearings are loose, stick each
bearing into the cup individually, relying on the grease to
hold the bearings in place until the spindle is installed.
Caged bearings versus loose bearings. Bearings come two
ways: loose, and in retainers. Both work fine. The retainer
conveniently holds the bearings while you work with them,
so if your bottom bracket has balls in retainers, use them.
Some folks argue that retainers add friction, but it's so little
that it's not worth worrying about. Fact is, when cup-andcone-style bottom brackets were the main type, most racing
team mechanics used the retainers because they sped up
bottom bracket overhauls.
One of the most difficult things to do is to explain which
way a retainer fits into a cup. Only one way works. Assembling
the bottom bracket with the retainer in backwards will prevent
will ruin something. Many a mechanic has been distracted
_41st long enough to Slide a kétNI. P18e011 13aelzwarcl q only ta
cover the error when he tries to eliminate the side-to-side
play later while adjusting.
Look at a retainer. There are two common types: one has
rounded edges and a fingertip-sized hole and the other has a
flat profile and a smaller hole. The rounded style is most
common. On both retainer styles, the metal frame that holds
the balls looks like a C in cross-section. On flat-style retainers,
the open side of this C should face in towards the shoulder of
the spindle. Thus, the open sides of the two retainers will face
each other when properly installed in the bottom bracket.
Round-style retainers are installed the opposite way.
After the bearings are installed, insert the dust sleeve. It
prevents contaminants from falling into the bottom bracket
shell from the frame tubes. If you don't have one, these sleeves
are available from bike shops.
Apply a liberal amount of grease to the whole surface of
the spindle, especially at both bearing shoulders. Grease
applied to the inner section of the spindle will serve to retard
corrosion. Take a close look at the spindle. Most likely one
tapered end is slightly longer than the other. If so, insert the
longer end into the bottom bracket first so that it emerges
through the fixed cup on the drive side of the bike.
Pack grease into the adjustable cup as you did the fixed
cup, and install its set of bearings.Then grease the threads and
screw it into the bottom bracket shell until you feel the bearings pressed snugly against the spindle shoulders. Thread the
lockring onto the adjustable cup and tighten it by hand.
Adjusting cup-and-cone-style bottom brackets. Now that
it's back in the frame, spin the bottom bracket spindle to make
sure the bearings are not binding. Also, try moving the spindle
up and down to check for looseness. If necessary, fine-tune
the adjustment by backing the lockring off a little and turning
the adjustable cup until the spindle spins smoothly but
without play. Once the adjustment is right, use the lockring
spanner to turn the lockring down very tight.
When tightening the lockring, watch the adjustable cup. It
may start to turn along with the lockring. If so, try holding it
still with a pin spanner. However, be aware the pin spanner
may not be able to resist the force of the lockring without
breaking a pin. If that looks like a possibility, loosen the lockring and adjustable cup together, then hold the lockring still
while you back the cup off a little further. Tighten them both
together and see if you end up with the correct adjustment.
Be patient. You may have to experiment to find the best
method to get the adjustment right. Just remember, when
fine-tuning the adjustment, don't try to move the adjustable
cup with your pin tool without first loosening the lockring.
If you try to do so, it's possible that you'll break the tool.
ILLUSTRATED BICYCLE
Put a crankarm on the spindle to check for any looseness
in the spindle adjustment. It'll give the extra leverage needed
to detect very small amounts of play. If the adjustment always
seems to be a little too tight or a little too loose, and you
simply cannot find the magic place in between, don't scream.
Just leave it a little on the tight side. Once the excess grease
works its way out of the bearings, it should be about right.
Installing the Crankarms
Reinstall the crankarms. Cottered crankarms should have the
cotters running opposite each other. If viewed while sitting
on the saddle with the crankarms at 6 and 12 o'clock, one
cotter nut should be facing forwards and the other should be
facing to the rear of the bike. If, after installing the cotters, the
arms are not exactly straight, try putting the cotters in the
other way. Or purchase new cotters (take an old one to the
shop to purchase ones that match).
Tighten the cotters with a cotter press (a special tool) or a
hammer. Trying to fully tighten them by means of the nut on
the cotter will strip the threads, ruining the cotter. If you're
using a hammer, give the back end of the cotter several sharp
blows, then tighten the nut until it's snug. Give the cotter a
couple more raps with the hammer and retighten the nut.
After your first ride, check to see if the nut is still tight. Check
again after a few hundred kilometres (or around 200 miles).
To reinstall a cotterless crankarm, put the arm on the
spindle, thread on the nut or bolt, and tighten fully. Expect to
use a good bit of force. Don't put all your weight behind it,
but snug the nut or bolt down firmly. If you have a torque
wrench to gauge your force, tighten it to between 25 and 30
foot-pounds.
One common practice you should avoid is greasing the
spindle tapers before installing the cotterless crankarms, unless
the crankarm manufacturer specifically prescribes it. Most
crankset manufacturers recommend that the spindle tapers be
free of lubricant. Exceptions to this rule include RaceFace
and a few late-model mountain bike crankarm sets manufactured by Shimano. If you're unsure, play it safe and keep
everything clean. Greasing a spindle taper for a crankarm set
not intended for greased tapers can result in the crankarms
working their way up the flats until the arms bottom out
against the ends of the spindle.
Another rare exception to this rule is crankarms that
develop a chronic creaking noise. It's usually caused by corrosion between the steel spindle and the aluminium crankarm,
and it usually occurs on cranksets with bottom brackets that
use a nut-style spindle. It's okay to apply a trace of grease to
this type of crankset to eliminate the creaking because the
tapers on the spindle are long enough to make bottoming the
crankarm unlikely.
Retighten the crankarm bolts after your first ride, and
check them periodically thereafter.
Remove chainrings. Most cranksets have removable chainrings. Get them off by loosening the bolts that hold them in
place (there are usually five). Sometimes, these bolts require a
10 mm or 11 mm spanner, but these days, most require a 5
mm hex key. Sometimes, you'll also need a chainring nut
spanner, to hold the nut on the back side of the chainring.
These are available through bicycle dealers, but if you can't
get one, a large flathead screwdriver will sometimes work in
its place.You also might find that the chainring bolts are very
tight and that you have to slide a small piece of pipe over the
hex key to get enough leverage.
Crankset Maintenance
There's very little maintenance that can be done on a
crankset, short of a complete overhaul, but there are a few
preventive measures worth taking. We've already suggested
checking the tightness of cotters and crankarm bolts at the
end of the first ride after their installation. It is also good to
recheck it at least monthly because riding on loose crankarms
will usually ruin them. It's good to check pedal tightness, too,
because loose pedals can also damage the crankarm if they're
ridden enough.
When you check the crankarms, tug on them to see if the
bottom bracket adjustment has loosened. If yours is a cupand-cone-style bottom bracket, remove the play by adjusting
the bottom bracket (it's not necessary to remove the crankarm
for this). If it's a sealed-cartridge model, don't be concerned if
there's a trace of play. Lots of play, however, indicates that
something is wrong, possibly a worn-out bottom bracket.
If the crankarms get bent (in an accident, for example),
only steel ones can be safely bent back. Bent aluminium
models should be replaced because they usually break when
straightened (sometimes well after being straightened). Bent
spiders can be straightened in many cases, even on aluminium
cranksets. The same is true for aluminium or steel chainrings.
Straightening a chainring is not too difficult. However,
straightening a bent crankarm is a job best left to a bicycle
shop. Without the proper tools and knowledge, you might
further damage the components. Inspect each crankarm thoroughly for cracks that may cause it to fracture under hard
pedalling pressure.
To straighten a chainring, it's best to leave it on the
crankset and bike. Straighten it by tapping on it with a
hammer in the direction in which it needs to go. Sight from
above as you turn the crankarm by hand. Use the front
derailleur cage as an indicator to determine where the ring is
out of true. Hit the ring lightly at first, then harder, until you
get the feel for what it takes to bend it. To get at a hard-toreach spot, place a screwdriver on the warp and hit the screwdriver's handle with the hammer. To pry out a bent tooth or
an extreme bend in a ring, use an adjustable spanner after
tightening the jaws enough so they just slip over the ring.
CRANKSETS 113
If you misuse the crankarm removal tool, the result is usually stripped cotterless crankarm threads, which means it'll be
impossible to remove the crankarm with the tool. It may
seem like there's no way to remove the crankarm, but there
is. Remove the bolt and ride around for a while. Eventually,
the crankarm will loosen and come right off.
Another possible glitch is stripped pedal threads in the
c-rankarm, usually the result of forcing the wrong pedal into
an aluminium crankarm. Sometimes it's possible to repair this
problem, though it's a job for a shop with the right tools.
SOLUTION: The
bearing retainer(s) are installed upside
down. Remove and reassemble correctly.
PROBLEM: You bent the bearing retainer when you
took the balls out to clean them.
SOLUTION: Try to straighten it, or replace it. If that's not
possible, toss the retainers and install loose ball bearings in
the bottom bracket.
PROBLEM:
TROUBLESHOOTING
PROBLEM: The
large chainring flexes, causing the chain
to rub against the front derailleur cage all the time.
SOLUTION: Learn to pedal faster (about 90 rpm is a good
goal), which will put less pressure on the chainring and flex
it less. Check for loose chainring bolts. Get the chainring
straightened if it's bent.
PROBLEM:
There's a knocking sound when you pedal.
SOLUTION: If you have a sealed cartridge bottom bracket,
moisture may have penetrated the threads between the
bottom bracket and the shell, causing light corrosion. This
is especially common with aluminium frames. Remove the
crank and bottom bracket, clean the threads of both with a
wire brush, wrap plumbers' Teflon tape over the threads and
reinstall the bottom bracket. For those with a nonsealed
bottom bracket, this sound usually comes from a loose fixed
cup (the right-side one). Tighten it securely by turning it
anticlockwise.
There's a trace of play in the sealed bottom
PROBLEM: The fixed cup on a nonsealed bottom
bracket continually loosens.
bracket.
SOLUTION: Tighten the retaining cup/ring; it may have
loosened slightly in the frame.
PROBLEM: There's
a creaking sound when you pedal.
SOLUTION: Tighten the crankarm bolts. If the arm still
creaks, remove it, apply a trace of grease to the spindle and
reinstall the arm.
SOLUTION:
Back it out (on modern bikes it's usually
turned clockwise), clean the threads, apply thread adhesive
and reinstall tightly.
PROBLEM: You stripped the crankarm threads and now
you can't remove the crankarm.
SOLUTION:
PROBLEM: You
removed the chainrings and now the
front derailleur won't shift correctly.
Ride the bike around the block a few times.
The crankarm will loosen and you'll be able to take it off.
PROBLEM: You
crashed and have bent a chainring.
SOLUTION:
You may have installed a chainring upside
down. Remove the rings and put them on correctly. Usually,
the crankarm bolts fit in indentations on the chainrings.
Sight from above, too, to make sure that there's even spacing
between the rings.
PROBLEM: You're trying to remove the chainring bolt
but it just spins.
SOLUTION: On the trail, try pounding it straight with
a rock. At home, use an adjustable spanner (make the
jaws just wide enough to grab the ring) to pry the ring
back into place. If it's really bent up, replace it.
PROBLEM: You
SOLUTION:
SOLUTION:
Hold the back half of the chainring bolt with a
wide flathead screwdriver or get a chainring bolt spanner.
PROBLEM: After
you overhaul the bottom bracket, the
adjustment is either tight or too loose.
broke a tooth off the chainring.
Don't worry about it. It should still work
okay. If it's causing the chain to run rough, file down any
protruding pieces.
114
ILLUSTRATED BICYCLE MAINTENANCE
Crankarm Adjustment
1
From time to time, grab the crankarms on your bike with your
hands and tug on them to check for looseness either in the crankarms
themselves or in the bearing adjustment inside the bottom bracket
(see photo). If you discover that the crankarms are loose, tighten them
immediately. Even if they never feel loose, at least once every 2 months
give them a preventive tightening.
Coffered crankarms are held in place by cotters that have nuts threaded
on one end. To tighten these crankarms, give the head of each cotter a sharp
rap with a hammer, then use a spanner to tighten the nut (don't overtighten
because the threads on cotters are delicate).
'' ,411111.
2
Tighten cotterless crankarms by turning the bolts clockwise. Modern
cranks have hex key bolts. On older models, you might have to
remove a dustcap. To remove a dustcap with a slit across its face, use a
wide-blade screwdriver or a large coin. Other types are can be removed with a
hex key. A dustcap with a slit near the edge can usually be pried out using a
screwdriver (see photo).
3
a101.
AMIN;
Once the dustcap is out, tighten the fixing bolt or nut that holds the
crankarm on the end of the spindle. Special crankarm bolt spanners
are made for turning these bolts. A thin-walled socket spanner of
the correct dimension will also work. Some crankarm removal tools are also
designed to double as crankarm bolt spanners (see photo). Such tools must be
turned with the aid of an ordinary open-end spanner. Use the appropriate tool
to snug up the crankarm fixing bolt, then, if necessary, replace the dustcap.
CRANKSETS 115
4.
When you tug on the crankarms, if there's play in the bearings and it's
a cup-and-cone-style bottom bracket, adjust it. You can do this without
removing the crankarm. However, it'll be easier if it's out of the way.
To remove the crankarm, follow the instructions on page 116.
To adjust cup-and-cone bottom bracket bearings, the lockring does not have to
be removed, only loosened. Use a lockring spanner to turn it anticlockwise (see
photo). Don't spin the lockring all the way off, just loosen it enough so that it
doesn't hinder the movement of the adjustable cup.
Some adjustable cups have pinholes, others have notches or spanner
flats. Use the appropriate tool to turn the cup clockwise to eliminate the
play in the bearings (see photo).
Work carefully. You may need to move the cup just one-eighth turn or less to
get the adjustment you need. Check frequently by grabbing a crankarm and
moving the spindle around. When there's no binding or play in the bearings,
retighten the lockring to hold the cup in that position.
As you tighten the lockring, watch the adjustable cup. It may try to move
along with the lockring, spoiling your careful adjustment.
(...‘ If the adjustable cup moves, hold it still while tightening the lockring
(see photo). If your cup tool is a pin spanner, it's possible to break the
) tool by putting too much pressure on the pins. Pay attention to how
much pressure it takes to prevent the cup from moving along with the lockring.
If a lot of force is involved, you should resort to a different technique. Calculate
how far out of adjustment the cup moves when you tighten the lockring, then
loosen both the lockring and cup. Hold the lockring still while backing off the cup
adjustment enough to compensate for its expected later movement. Then when
you retighten the lockring, the cup should end up in the right place. If you
removed a crankarm, replace it. Tighten the crankarm bolt, then reinstall the
dustcap (if there is one).
116
ILLUSTRATED BICYCLE MAINTENANCE
Bottom Bracket Overhaul
I
Get together the tools and supplies needed (see illustration on page
108). You'll also need, at the most, 22 of the 1/4-inch bearings. Decide
now if you will want to have the pedals off the crankarms anytime
during the overhaul. If so, remove them now, while the crankarms are still on
the bike. Modern crankarms are held in place by hex key bolts. Remove these
by turning anticlockwise. Be sure to remove any washers beneath the bolts.
Older crankarms may have dustcaps protecting the threads that are used in
the crankarm removal process. Dustcaps are easily damaged, so treat them
gently. Pry the dustcaps free with a screwdriver if they have slits near the
edges (see photo).
2
If there's a slot or hexagonal hole in the
centre, turn
the dustcap
anticlockwise to remove it, using a screwdriver, a coin or a hex
key. There's either a nut or a bolt holding the crankarm on the
spindle. If your crankarm extractor has an end made to fit this fixing bolt, use
that, along with a spanner, to turn the bolt anticlockwise. Otherwise, use a
crankarm bolt spanner or a thin-walled socket. Extract the fixing bolt all the
way out of the spindle and set it aside, along with its washer. If you have the
type of crankarm that's held on with a nut rather than a bolt, there is no separate washer because the nut has a serrated edge that acts as a built-in washer.
If a hex key bolt holds on the crankarm and it won't loosen, go to step 4.
3
Study the crankarm extractor. As you twist the movable part, a rod
that runs down the centre of the tool moves either in or out. Adjust the
tool so that the rod retreats as far back inside as it can. Thread the end
of the tool inside your crankarm.
As you begin to insert the tool, make certain that its threads mesh with
those inside the crankarm. Thread the tool in as far as you can, then place
a spanner on the spanner flats and advance the inner rod forward until it
butts against the end of the spindle (see photo). Continue turning in the same
direction, pushing the rod against the end of the spindle, which will pull the
crankarm off the spindle.
CRANKSETS 117
Cotterless crankarms with a built-in system for crankarm installation
and removal with a single hex key are now quite common. In this
design, the dustcap and crankarm fixing bolt are both used in the
crankarm removal process. A hex key is inserted through the dustcap into the
head of the crankarm fixing bolt. As the bolt backs out, it pushes against the
dustcap, forcing the crankarm off the spindle (no special tools required).
Remove both crankarms from the spindle. Use a lockring spanner and
loosen the lockring found on the left side of the bottom bracket by turning
it anticlockwise (see photo). Spin the lockring completely off the bike.
raw. Use your pin spanner to turn the adjustable cup anticlockwise until it is
threaded almost all the way out of the bottom bracket shell.
6
Unless you know that your bearings are held in a retainer, turn the
bike on its side and spread paper towels or rags under it to catch any
of the bearings because they're inclined to roll away. Though you'll be
replacing these bearings, keep track of them to inspect them for signs of wear
that indicate potential damage to other parts. Also, that way you can count
them to make sure you have the right number of replacements (usually there
are 22 of the 1/4-inch bearings).
Hold the spindle in place with one hand to trap the fixed cup bearings while
removing the adjustable cup with the other hand.
118
ILLUSTRATED BICYCLE MAINTENANCE
7
Once the adjustable cup bearings are out, remove the plastic dust
sleeve, if one is present, along with the spindle and the bearings
from the fixed cup side. Don't remove the fixed cup (on the drive side
of the bike) unless it has loosened (look for a gap between the cup's lip and
the frame). Remember: some cups turn clockwise for removal.
8
I
Clean the metal parts with a solvent and a rag or stiff brush.
Thoroughly clean inside the fixed cup and the bottom bracket shell.
After you've cleaned all the parts, inspect them closely for signs of damage
or excessive wear. Look at the adjustable cup. You'll see a score line running
in a circle where the bearings made contact with the race. Look for any
irregularities in the surface of the race along this line. Is one part of the line
worn more heavily than another? Are there any pits along the line that might
cause a bearing to snag?
9
._ _,......
Inspect the fixed cup. Since it's still in place on the bike, a torch
may help. Study the spindle. Look along each shoulder for the wear
line where the bearings make contact. Are there any pits or signs of
excessive wear? Clean and examine all of the old ball bearings. Are any of
them cracked or chipped? If the bearings are caged in a retainer, is the
retainer still intact and free of damage?
If there are any broken parts, check inside the bottom bracket shell again to
make sure no metal fragments are clinging to the frame. You don't want them
hanging around to do damage after you've reassembled the bottom bracket.
Replace any excessively worn or damaged parts.
CRANKSETS 119
If in doubt, take the part to a knowledgeable bike mechanic
for a second opinion. If your fixed cup needs replacing, have
1(
it done at a bike shop. It's very difficult to adequately tighten
a fixed cup without a tool too specialized and expensive to be worth your
purchasing (see photo). Try tightening it with a spanner after applying a
-
few drops of thread adhesive. If it loosens, however, have a shop mechanic
tighten it professionally.
If you haven't already purchased new bearings, collect and count the old
ones to know how many to buy. Take a sample to the bike shop to match the
size. If you have caged bearings, take one of the old retainers to the shop to
get two new ones to match. Or, gently pop out the old bearings and press in
new ones to reuse the retainers.
1 1 Begin reassembling the bottom bracket by packing plenty of
medium-weight grease into the fixed cup. Push the ball bearings
into the grease, which should hold them in place until the spindle
is in place. Caged bearings must be installed in the correct way. To determine
what that is, take a close look at a set. Note that individual balls are separated from one another by small metal fingers that form a sort of C shape.
There are two retainer types: one with a round profile, and another with a
flatter profile. The latter is correctly installed when the cup shape or open side
of the C formed by these fingers faces in towards the centre of the bottom
bracket. Or, to put it another way, the individual metal fingers of the retainer
curl towards the inside of the bottom bracket (see photo). The former type
goes the opposite way.
2 Onc e the bearings are in place inside the fixed cup, the spindle
can be replaced. This too has to be turned in the right direction
1 Almard since the ends of most spindles are asymmetrical. The difference
may not be obvious at first glance, but on most spindles the distance between
the tapered end and the adjacent bearing race is slightly greater on one side
than on the other (see photo). If the manufacturer's name is on the spindle,
install the spindle in such a way that if your bottom bracket were transparent
you could read the name while sitting on the bike. Otherwise, make sure the
longer end is on the drive side, where the extra length is needed to compensate for the space taken up by the chainrings.
1 20 ILLUSTRATED BICYCLE MAINTENANCE
13
If you have a plastic dust sleeve, clean off all the old grease
and grime. Hold the spindle in place on the fixed cup side
while sliding the sleeve in over it.
14
Pack the adjustable cup with grease and insert the bearings.
Once again, if using caged bearings, be sure to put them in the
correct way. Put a little grease on the threads, then carefully
screw the adjustable cup back into the bike frame by hand (see photo).
15
Thread the adjustable cup clockwise into the frame until you
contact the bearings. Back the cup off about one-eighth turn,
then grasp the spindle and twirl it back and forth to check the
adjustment. If you feel any binding in the bearings, the adjustment is too tight.
Use your pin spanner to back the cup out a tiny bit, then check the adjustment
again (see photo).
After you're sure the adjustment is not too tight, try moving the spindle up
and down. If there's any play in it, the adjustment is too loose. Twist the cup
clockwise a short distance and check again. When you feel neither looseness
nor binding in the bearings, screw the lockring back on.
CRANKSETS 121
Try tightening the lockring down without using a tool to hold
the cup still. If the cup insists on turning with the lockring, fry
holding it still with the pin spanner while turning the lockring
(see photo). If you feel a lot of force being put on the pin tool, stop using it or
it may break. Loosen the cup and lockring together, then hold the lockring still
while you back the cup out a bit more. Now tighten both together and see if
your adjustment is correct.
Even if you had no problem with the cup turning, check the adjustment again
after tightening the lockring, since that procedure may alter your cup adjustment. When you're satisfied with the adjustment, replace the two crankarms.
Be sure you do not put any grease on the end of the spindle.
17
Push a crankarm onto the end of the spindle, then tighten the
nut or fixing bolt to pull the crankarm into place (see photo).
When both crankarms are tight, tug on them laterally to check
again for looseness in the bottom bracket and twirl them to check for binding.
If you are not satisfied with your adjustment at this point, you may be able to
alter it without removing a crankarm again. Loosen the lockring, adjust the
cup as needed, then retighten the lockring. Once everything is okay, replace
the pedals (if you removed them earlier) and lift the chain onto the chainring.
Finally, don't forget to replace the dustcaps (if necessary). They protect the
threads inside your crankarms, which you'll need to use the next time you
overhaul your bottom bracket.
1 22
ILLUSTRATED BICYCLE MAINTENANCE
Removal and Installation of
a Shimano Octalink Crankset
1
Shimano's Octalink design was the first widely accepted, spline-fit crank
and bottom bracket standard. There are now two Octalink standards:
Octalink V-1 and Octalink V-2. In recent years, a consortium of smaller
manufacturers including Chris King, RaceFace and Truvativ developed a competing standard called ISIS (International Spline Interface Standard). None of
the three designs are cross-compatible, so it's important to know what you have
before replacing parts, even though all adhere to the same procedure for installation and removal.
If you're lucky enough to have self-extracting crankbolts, removal will be as
2
simple as loosening them with an 8 mm hex key.
IMILL-
If your crankarms are not equipped with self-extracting bolts,
remove the crankbolts and washers, then extract the crankarms using
a crankarm removal tool similar to, but not the same as, the one used
for tapered crankarms. Because Octalink and ISIS spindles are larger and have
a larger bolt hole in the spindle end than square-taper types, you will need
a crankarm extractor with a larger tip such as the Park Tools CCP-4. If you
already have an older cotterless crank puller, it's sometimes possible to find
a steel slug that will fit on the end of large spindles, which will enable you to
use your older tool.
3
If you have self-extractors, reinstallation begins with the removal of
the self-extracting hardware. Using a small pin spanner or a crank
dustcap remover (often integrated as the opposite end of a chainring
nut spanner) turn the dustcaps anticlockwise. Keep all the parts of the extracting
hardware in order.
CRANKSETS 123
4
Cover the splines on the spindle and inside the crankarm with grease,
and then carefully line up the splines. Tightening the arms in place
without the splines properly meshing can cause permanent damage,
uining an expensive crankarm.
.....
MI.
Install the crankarm fixing bolt and steel washer with your 8 mm
hex key. The recommended tightening torque for this bolt is generally
between 300 and 400 inch-pounds. Your crank manufacturer will have
specific numbers in mind, but in plain terms it translates to very tight. With
these new spline systems, you tighten the crankarm until it bottoms out, taking
a lot of the guesswork out for those who don't have a torque wrench available.
6
If you don't have self-extractors, you're finished. Those that do need
only replace the plastic washer and retaining ring that complete the
self-extracting system.
1 24
ILLUSTRATED BICYCLE MAINTENANCE
Chainring Maintenance
1
It's a good idea to keep chainrings clean. A lot of grease mixed with
road grime is passed on to the teeth of the chainrings by the chain.
The abrasives in this grime cause the chain and chainrings to wear
out at a faster rate than they otherwise would.
Therefore, at least once a month – preferably more often, especially if you do
a lot of riding on wet and dirty terrain – take a rag and wipe your chainrings
clean. Dampen the rag with a little solvent, if you need to, or use a stiff brush
to loosen the grime so it can be wiped away (see photo).
Of course, it does little good to clean chainrings if you never bother to clean
your chain. The two work together, get dirty together and wear out together,
though not necessarily at the same rate. Thus, whenever you clean your
chainrings, you should also give your chain a thorough going over. For details
on chain cleaning and lubrication, see page 149.
....,
...
Sometimes a chainring gets bent in a crash, or two chainrings are so
close together that when the chain is on the smaller one it rubs against
the larger one. The solution to the first problem is obvious: straighten
the bent area. To solve the second problem, you need to bend the larger chainring slightly away from the smaller all the way around its circumference.
Both these repairs can be accomplished with a hammer or with the help of
3
chainring bending tool (see photo). This is a simple tool, one that is less
expensive than most specialized bike tools. However, bending a chainring
Is a job you may prefer to leave to an experienced bike mechanic. If the
Droblem
is quite severe, you are better off just replacing the chainring.
f you see shiny cuts on the sides of the chainring teeth, you are riding in
year combinations that force the chain into extreme angles. One extreme
xcurs when you ride with the chain on the large chainring and the largest
-ear cog. Another results from the chain being shifted onto the smallest chaining and the smallest rear cog. Such gear combinations should be avoided.
CRANKSETS 125
3
When you start riding with a new chain and new chainrings, the teeth
of the rings should mesh perfectly with the links of the chain. Over a
period of time, the teeth on the rings will gradually become thinner as
they wear down. Meanwhile, the plates on the chain will gradually cut into the
sides of the pins or rivets, causing the chain to increase in length slightly. As
long as the chain and chainrings wear at the same rate, their performance
should be satisfactory. However, this is not likely to be the case. Eventually,
both will wear out and need to be replaced.
Replacing chainrings is usually an easy process. Normally, they're attached
with hex key bolts to a five-armed spider that radiates out from the base of
the right crankarm. Simply remove the five bolts (if they're stuck, hold their
backs with a flat-blade screwdriver) while holding the ring in place, then
slide it off the crankarm (see photo). Slide on a new ring and bolt it in place
(always grease the bolts first).
4
As a preventive measure, check periodically to make certain that all
the chainring bolts are tight.
1 26
ILLUSTRATED BICYCLE MAINTENANCE
Sealed-Bearing Cartridge-Sy
Bottom Bracket Installation
1
Remove the old bottom bracket with the splined removal tool. Turn the
left-side cup first, anticlockwise, until it comes out of the frame. Then
turn the right-side cup clockwise to remove the cartridge. If the cups
won't turn, don't force them. Apply a penetrating lubricant to the cup edges
and tap the bottom bracket shell with a hammer to work the solvent into the
threads. Wait and try to turn the cups again. Repeat this procedure until the
cups unscrew, or take the bike to a shop for help.
Cartridge-sealed bottom brackets come packed with grease and adjusted
from the factory. Before installing the new one, turn the spindle by hand to
feel how it turns – how the factory adjustment feels. Later, when it's installed,
the spindle should turn just as easily as it does now.
Cartridge bottom brackets usually have one cup preinstalled on the drive side
of the cartridge. If the bottom bracket is being installed in a titanium frame,
coat the threads with Finish Line Ti-Prep or some other anti-seize compound.
Wrapping plumber's Teflon tape around the cup threads is also acceptable
(see photo).
9
Treating the threads will prevent chronic clicking noises from the
AVORMW
bottom bracket area and will fight galvanic corrosion, which can
freeze the bottom bracket into the shell. (Grease is usually adequate
for steel and aluminium frames.) Start threading the cartridge into the drive
side of the frame by hand-turning it anticlockwise (see photo). Be careful not to
cross-thread it.
CRANKSETS 127
3
4
When it gets tough to turn, install the splined tool (see photo) and
continue turning until the cup is snug and fully screwed into the frame
(it'll only go so far because of the built-in lip on the cup edge).
Install the other cup (be careful not to cross-thread it), turning it clockwise with the splined tool until the cup bottoms against the cartridge
(see photo). Check how things are going by turning the spindle by
hand. If it's a lot tighter than it was before installation, it's likely that the cup is
going in crooked. Remove it and start again, making sure it's straight. When
the cup is secure, check the installation by putting the spline tool on the drive
side again and making sure it's tight, then double-checking the tightness of the
left-side cup. Finally, grab the spindle and turn it. It should feel smooth, like it
did before installation. If not, try again. When the bottom bracket is installed
correctly, attach the crankarms. Remember to snug the bolts after the first ride
and monthly thereafter.
There are many different cartridge-style bottom bracket designs today, with
more coming along almost daily. The preceding directions apply to the
common types. If yours seems different, follow the manufacturer's installation
instructions. If you don't have the directions, get them from the dealer who
sold you the bottom bracket, contact the manufacturer or check its Web site.
1 28
ILLUSTRATED BICYCLE MAINTENANCE
Removal and Installation of
Two-Piece Cranksets
1
Shimano and RaceFace two-piece cranksets are removed and installed
in very similar manners. Since Shimano's procedure is slightly more
involved, we will focus on that system here and point out where
RaceFace's procedure differs. The first step in removing a Shimano two-piece
crankset is to loosen the two pinch bolts on the left crankarm with a 5 mm
hex key. These bolts clamp the arm in place on the spindle.
2
Next, use Shimano's crank arm installation tool (TL-FC16) to remove
the preload cap by turning it anticlockwise. Park Tool also makes a
tool that can be used for this (BBT-9). You will find that the left
crankarm will slip easily off the spindle.
Notice that there is a broad spline on the spindle and inside the crankarm,
making it nearly impossible to misalign the left crankarm when you reinstall
it. There will also be a thin, black rubber 0-ring on the spindle between the
bearing and crankarm. Remove this from the spindle and set it into its seat
on the crankarm to keep track of it. RaceFace cranks forego the use of pinch
bolts and preload cap. Instead, the right-side arm is affixed to the end of
the spindle in a fashion typical of other spline-interface cranksets. Turn the
crankarm fixing bolt anticlockwise with an 8 mm hex key to pull the
right arm off the spindle on its own.
CRANKSETS 129
The spindle will now smoothly slide out of the bottom bracket. If
it's not cooperating, there may be some trace amounts of corrosion
on the spindle. Give the end of the spindle a few light taps with a
rubber mallet to loosen it.
Remove the bottom bracket cups from the shell using an appropriate spanner. Shimano's part number for this tool is TL-FC32; Park
Tool's BBT-9 will also work. Most road and mountain bikes today
will have an English-thread bottom bracket shell, so the left-side cup will
come out when turned anticlockwise, but the right-side cup must be turned
clockwise in order to remove it.
10.
Installation is as simple as reversing these steps. With Shimano
cranks, don't overtighten the preload cap that holds the left crankarm
in place. This cap is intended only to snug the crankarm in place and
should be only slightly more than finger-tight. Last, tighten the pinch bolts
incrementally to be sure they are both properly and evenly torqued.
CHAPTER 7
Freewheels and
Cassettes
In the mid- to late nineteenth century, people rode bikes
The ratcheting mechanism is made up of bearings, a gear
called velocipedes and high-wheelers. The former had equal- and pawls. The pawls are angled one way and rest on springs.
size wheels like most of today's bikes, except that the crankset When coasting, the gear spins past the pawls, which trip over
was rigidly attached to the front wheel. The high-wheeler,
the gear teeth, making the fast clicking sound you hear. When
which was invented after the velocipede,
you pedal, however, the pawls engage the
shared this trait; however, the front wheel
gear teeth, driving the bike.
was huge (up to 60 inches in diameter)
The cogs — or sprockets, as they are
because inventors realized that with an
sometimes called — are disks with teeth on
increased wheel size, riders could go faster.
them. The number of teeth on the cog
High-wheelers had a dangerous drawcombined with the number of teeth on the
back. Bringing the bike to a stop too
chainring determines the gear ratio of the
abruptly would result in the rider getting
bicycle's drive system at any given time.The
pitched over that tall front wheel. With legs
larger the cog, the easier it is to pedal; but
trapped behind the handlebar, the
the larger the chainring, the harder it is to
common result would be the rider landing
pedal. Cogs and chainrings are commonly
squarely on his head (almost all riders were
referred to by the number of teeth on them
men in these, the days before the women's
(they're usually stamped with the number,
suffrage movement). 'Taking a header' was
so you don't have to count to determine
all-too-often fatal, and so a safer design was Freewheels and cassettes are built up
size). The more cog and chainring combisought. In the 1880s, the idea of a chain- with a combination of different-sized
nations you have, the greater the number of
driven rear wheel was developed and the cogs and spacers that separate the
available gear ratios and the greater the
Safety bicycle was born. Safety bicycles cogs evenly.
variety of terrain on which you can ride. A
mostly resembled the bicycles of today,
cluster of different-sized cogs and the
except that they had a fixed drivetrain, which meant that spacers that divide them is known either as a freewheel or a
whenever the rear wheel was in motion, so were the crank cassette, depending on the type of ratcheting mechanism to
and pedals. Although this 'fixed gear' system allowed you to which it is connected.
contribute the strength in your legs to the braking process by
resisting the forward movement of the pedals, it never made The Difference between Freewheels
for very comfortable or very safe riding. Fixed gear drivetrains and Cassettes
still can be found today on track bikes (one-speed bikes raced When derailleur drivetrains were first invented, there had to
on an oval track called a velodrome) because of the added be a way to attach multiple cogs to the rear wheel of a bike
control that it offers track racers, whose machines do not to provide different gears. For the gearing, inventors came up
have brakes.
with the freewheel, which is an integral unit comprising the
With the exception of the track bike, modern bikes are cogs (usually five, six or seven) and spacers attached to a
equipped with a ratcheting mechanism and cogs that connect ratcheting mechanism in the centre that drives when you
the rear hub, via the chain, to the pedals but allow you to pedal but allows coasting (freewheeling) when you stop
coast when you stop pedalling. This makes bikes safer and pedalling. This centre section comprises the bearings, gear and
much more comfortable to ride, thanks to the various gearing pawls is called the freewheel body. There are threads in the
it provides. This device is called a freewheel because it frees centre of the freewheel so that it can be screwed onto the rear
wheels hub.
the rear wheel from the connection to the crankarms.
1 32
ILLUSTRATED BICYCLE MAINTENANCE
The Modern Cassette
■ HUB
FREEWHEELS AND CASSETTES 133
To remove the freewheel, a special tool is needed called
(naturally) a freewheel remover. Each brand of freewheel has
its own remover. Freewheels can be difficult to remove
because pedalling pressure tightens the freewheel on the hub.
If it's not adequately lubricated or if a strong, powerful rider
has been racing the bike, the freewheel can become very
tight. Another tricky thing with freewheels is cog removal.
This varies from brand to brand, but on most freewheels,
there are cogs that thread on and those that slide on. It's
important to know what you're dealing with before
attempting to replace a cog.
Another interesting thing about freewheels is how they
affect the design of the hub. Because of the spacing requirements of the freewheel, the hub bearings on either side of the
hub can be only a certain distance apart.
It's precisely these shortcomings that led to the development of the cassette system.You can still get freewheels today
on certain bikes, but the vast majority of new models are
equipped with cassettes — and have been since the late 1980s.
At a glance, cassettes look just like freewheels, but there are
significant differences. The basic one is that the ratcheting
mechanism on a cassette system is part of the hub (called a
freehub or cassette body). It's not screwed onto the hub, it's
built into the hub. (Remember that on a freewheel system,
the freewheel is threaded onto the hub, not built into it. This
provides one of the main advantages of cassette hubs: it allows
the bearings on either side of the hub to be placed further
apart, which increases support for the axle, strengthening it
and preventing it from breaking in most cases.
Another big advantage is simple cog removal. All that's
required is unscrewing a lock ring or the bottom cog or cogs
(depending on model), and the cogs can be lifted off the hub
as a unit or as a cassette. Then you can simply slide on a
replacement cassette (or one of a different size if, for example,
you're changing cogs to make the gearing easier).
It's important to understand the differences between cassettes and then determine which type is on the bike you're
working on. Cassettes are found on most modern bikes and
can be identified by looking for a flat lockring on top of the
smallest cog. The lockring is splined in its centre. Freewheels
are mostly on older bikes. Usually freewheels have two
notches built into the freewheel body or a splined pattern just
visible inside the freewheel body. There is no lockring. If
you're in doubt, a shop mechanic can quickly identify the
type if you bring in the wheel. Once you know what you
have, both are easy enough to work with.
Cleaning and Lubricating a Cassette
or Freewheel
Most of the time when you clean a cassette or freewheel, you
clean only the outside. This is because the outside gets the
dirtiest.You don't have to remove the cassette or freewheel to
clean it, so it's an easy job. Just wipe it down with a rag. When
the cogs are clean, give the cassette or freewheel a spin. If it
feels or sounds dry, drip some medium-weight oil into it
through the crack in the body.
There's little need to overhaul a cassette hub or freewheel
body because the moving components work only when
they're not under a load. If the body produces a grinding
sound, as if it has sand or dirt in it, all that's usually required
is to flush the body with oil to remove the dirt.
To clean the cogs, lift the chain off and remove the rear
wheel from the bike. Take a rag and wipe the dirt from the
surface of the cogs. Use the edge of the rag to clean between
the cogs, or use a small screwdriver to dig out dirt or debris
that may have got jammed in, then wrap the rag around one
finger to clean in the troughs of the teeth.
It's usually possible to lubricate the cassette hub or freewheel body by squirting some medium-weight oil into the
opening between the inner and outer bodies. To find this
opening, rotate the cogs anticlockwise with the wheel sitting
horizontally on a table or the floor.The outer body will rotate
while the inner body remains stationary. Usually, you can see
the separation between the two (although sometimes you'll
have to remove the cogs to see it). That's the opening to put
the oil in. Rotate the outer body while applying the oil so
that it works its way into the internal parts of the body.
After applying the oil, wrap the rag between the cassette or
freewheel and the spokes to catch any excess that drains out.
If, after you've done this, the cassette or freewheel still makes
grinding sounds while coasting, repeat the lubrication
process. This time, however, you may wish to first use a light
oil and solvent mixture like WD-40 to try and flush out the
dirt. Then lubricate the body with medium-weight oil, as
before. If you use a stronger solvent, like kerosene, you may
have to lubricate your cassette or freewheel several times
before all the parts get coated with oil again.
Removing the Freewheel
There are four reasons to remove a freewheel: to replace a
worn one, to change a worn cog, to overhaul the hub and to
replace a broken spoke (because the freewheel makes it difficult to push the spoke through the hub flange).
To remove a freewheel, you need a freewheel removal tool.
These tools fit into special notches or splines on the freewheel
and allow its removal. Almost every type of freewheel requires
a different tool, one made especially for it. You can damage
the freewheel by trying to take it off with the wrong tool, so
it's very important to get the correct one.You'll probably have
to order it from a tool supplier because freewheels are no
longer the norm.
In addition to the freewheel tool, you'll need a large
adjustable spanner or a bench-mounted vice to fit the freewheel tool's spanner flats.
1 34
ILLUSTRATED BICYCLE MAINTENANCE
a lot of force to break the freewheel free. If your freewheel
proves quite stubborn, you may have to get a bigger spanner
or slip a length of pipe over the handle of your spanner to
get extra leverage.
Once the freewheel begins to unscrew, loosen and remove
the axle nut or quick-release skewer before continuing to
turn the freewheel removal tool. At this point, you may be
able to unthread the freewheel by simply turning the removal
tool with your fingers. If that's the case, take the entire quickrelease assembly off the wheel and set it aside.
If you still need the leverage of a spanner or vice to
unthread the freewheel, it's best to keep the tool fastened in
place while you turn it so that it cannot slip out of its grooves.
In this case, you'll have to continually unthread the fastening
nut or quick-release as you spin the freewheel off the hub. Do
this by holding still the axle or quick-release skewer on the
left side of the hub while you spin the freewheel, the removal
tool and the fastening nut anticlockwise on the right side of
the hub.Whenever the nut becomes too tight against the tool,
loosen it a bit by twisting the axle or skewer from the other
side of the hub.
Use an axle nut or quick-release skewer to hold the cassette lockring tool or freewheel remover in place and prevent damage caused
by the tool slipping free. Remember to remove the nut or skewer;
otherwise the lockring or freewheel won't unthread all the way.
Before removing the freewheel, remove the rear wheel
from the bike. Once the wheel is off, completely remove the
axle nut or the quick-release skewer nut from the freewheel
side of the wheel. Fit the freewheel removal tool into the slots
or splines made for it in the freewheel body, then tighten the
axle nut or the quick-release skewer nut down over it to hold
the tool securely in place. You'll be using a lot of force to
remove the freewheel. If the freewheel tool slips, it could
break the freewheel removal notches or the tool itself, so
make sure it's properly seated and firmly fastened to the freewheel before you apply pressure to it.
Set the wheel upright on the floor, with the freewheel side
pointing away from you. Fit a large adjustable spanner on the
flats of the freewheel tool so that as you bend over the wheel
you can push down hard with your right hand to break the
freewheel loose from the hub. If you prefer to use a benchmounted vice, bring the wheel down horizontally over the
vice and lock the freewheel tool in its jaws.
If you use the spanner, you must hold the wheel stationary
while applying force to the freewheel tool. If you use the
vice, the tool will be held stationary, so you must turn the
wheel to apply leverage on the tool. In either case, you must
twist the spanner or the wheel in an anticlockwise direction
to unscrew the freewheel from the hub. Because of the constant tightening action that results from pedalling, it may take
Removing Cogs
One of the advantages of cassettes is that they're easy to work
with, so jobs requiring cassette removal, such as replacing a
spoke or installing a new cassette or cog, take less effort. Once
the cog or lockring that holds the cassette on the cassette hub
is removed, the cassette is easy to take off the hub because it's
not threaded on. It's attached via splines, which makes cassette
removal and installation easy.
There are two types of cassettes, those held on the hub by
the first cog(s) and those held on the hub by a lockring.
Determine which type you have by removing the rear wheel
and looking at the centre of the smallest rear cog (remove the
axle nut or quick-release skewer first). If there's a splined
shape inside the centre of the rear cog, the cassette is a
modern model requiring a splined tool (lockring remover)
that fits inside the lockring. If there's no spline, the cassette is
an older design requiring two chain whips to remove. A chain
whip consists of a steel handle with a piece of chain attached.
If you have the tools and new cogs are available, you can
remove your old cogs.There are two reasons to replace a cog.
One is to get a different gear ratio. To accomplish this, you
:flange the cog to one with more or fewer teeth. The other
reason is simply because the old cog is worn out.
Cogs wear due to the friction of the chain against their
teeth. If a cog is worn out, you'll know it when you ride on
Lt. When you put a lot of pressure on the pedals, such as when
accelerating or climbing, the chain will skip over the worn
teeth of that cog. You can easily feel and hear this when it
lappens. The smaller the cog size, the quicker the wear,
b ecause there are fewer teeth to share the load.
FREEWHEELS AND CASSETTES 135
Replacing a cog is not particularly difficult, but you do
need the appropriate equipment. For modern Shimano and
Campagnolo cassettes, you'll need a lockring remover, a large
adjustable spanner and a chain whip. For older cassettes and
for freewheels, you'll need two chain whips. If you remove
the freewheel from the wheel, you'll need two chain whips
and a freewheel vice.
The freewheel vice is a special tool that has prongs to
clamp onto the largest cog of your freewheel. It must then be
held immobile between the jaws of a bench-mounted vice
while you use the chain whips to apply force to the cogs.
If you don't plan to change your freewheel cogs very
often, it might be a good idea to let a bicycle shop remove the
cogs for you, since that will probably cost you less than the
price of the tools needed to do the work. Also, before you
attempt to replace a cog, check with your local bicycle shop
to see if spare cogs of the type you need are available.
For modern Shimano and Campagnolo cassettes, disassembly is simple. Hold the large cog with a chain whip to
keep it from turning, place the appropriate lockring remover
in the splines of the lockring and turn it anticlockwise with
a large adjustable spanner. Remove the lockring, and the cogs
can slide off the hub.
If you're working on a freewheel and have a freewheel
vice, lock the freewheel in it. Remove the smallest cog by
wrapping the chain whip around it and using the handle to
turn the cog anticlockwise.
If you're using two chain whips, use one to hold the
freewheel steady and the other to remove the cog. Set the
tools on the cogs in such a way that you are able to squeeze
their handles together. This will give you good leverage while
preventing skinned knuckles. Be careful when you're using
the chain whips: If you don't keep the exerted force in line
with the cog, you can warp the cog and ruin it.
Look closely at the chain whips. Each has two sections of
chain: a short section attached at both ends to the handle, and
a long section with one end free. When you fit the tool onto
a cog, keep the gap between the two pieces of chain as small
as possible. This will minimize your chances of twisting the
handle out of line and warping a cog.
The most reliable method of all is to immobilize the freewheel in a freewheel vice and use two chain whips.This gives
you maximum control and leverage for the job.
Depending on the brand and how many speeds your freewheel has, you will usually have to remove between one and
five threaded cogs (on cassettes without lockrings, one or two
cogs are threaded, and the rest slide on). The remaining cogs
are notched and slide onto the freewheel body. (There are a
few exceptions — such as Regina freewheels, on which all the
cogs are threaded on — but they're pretty rare today.)
As you remove each of the cogs, lay them out in the order
and orientation they came off. This will ensure getting the
Cogsets for Campagnolo (top) and Shimano (above) are not
interchangeable. Though both companies use splined interfaces to
fit cogsets to their freehub bodies, the spline patterns are different.
As a result, cogsets need to be designed specifically for each brand.
cogs back on properly. Before you put the cogs back on the
body, check the order against the manufacturer's chart, if it is
available. Make sure the threads are clean and lubricated with
a light oil.
As you install the cogs, make sure that you don't put any
of them on backwards. There's no risk of this with modern
cassette cogs, which fit on the hub only one way. It's easy to
make mistakes with older freewheel and cassette cogs,
though. Remember that the side of the tooth that is sloped
(chamfered) usually faces the spokes. Most likely, you will discover that some cogs have no threads; they are held in place
1 36
ILLUSTRATED BICYCLE MAINTENANCE
by adjacent cogs.When replacing a cog that is threaded, handtighten it first, then tighten threaded cogs with a chain whip
so that each threaded cog is snug against the cog below it.The
cogs will tighten fully when you ride.
The first time you use this cassette, start out riding on the
largest cog, pedal a few feet, shift to the next cog and then
pedal a few more feet. Do this until you've seated all the cogs.
Installing a Freewheel
No tools are required to install a freewheel. Be sure the
threading on your freewheel and hub match before
attempting to put the freewheel on, and thoroughly clean the
threads on both the freewheel and the hub, then lubricate
them with a medium-weight grease before trying to put
them together.
Be careful while threading on a freewheel — its threads are
steel, and the hub threads are usually aluminium. If you crossthread the freewheel, you may strip the hub threads, which
will ruin it.
Apply grease to the threads inside the freewheel, then
hold it in one hand and steady the wheel in the other. Put the
freewheel against the hub and turn it anticlockwise at first.
This unscrewing action will align the fine threads of the freewheel and hub to prevent cross-threading. Once you feel the
threads drop into alignment, reverse direction to begin
threading the freewheel clockwise onto the hub.
Spin the freewheel on carefully for the first few turns. If
you meet any resistance, you've probably cross-threaded it.
Stop, remove the freewheel and try again. Once the freewheel
has been threaded down three or four full turns, you can
safely assume that you have it right; continue until it's tightly
threaded all the way on.
Special Maintenance Situations
Cassette hubs combine the inner workings of the freewheel
and the hub into one unit. In this system, the freewheel
mechanism and hub can usually be separated with a 10 mm
hex key Replacement freewheel mechanisms are not always
easy to get and rarely fail, though, so this procedure is usually
best left to a shop mechanic.
Generally speaking, all types of freewheels and cassettes are
very dependable. Basic maintenance requires only that you
wipe away any surface dirt and drop a little oil into the bearings periodically. Developments over the last several years of
indexed shifting systems and increasing numbers of cogs —
nine or ten fit into about the same space that once held seven
or eight — have led to thinner cogs with short, radically
shaped teeth and slender chains to improve shifting. Add the
use of exotic materials and the practice of combining
multiple cogs of a set on alloy carriers to save weight, and
you will find that a cluster of cogs will wear much more quickly
than five- or six-speed cogs ever did. As a result, replacing
individual cogs has all but become a thing of the past.You can
maximize the life of your modern cassette by replacing your
chain periodically — every 1,200 to 1,600 km (750 to 1,000
miles) on the road, and more often when mountain biking or
riding through bad weather. Any but the lightest of us putting
more than 2,400 to 3,200 km (1,500 to 2,000 miles) on a
single chain and cogset will most likely need to replace the
entire cassette and chain at the same time.
TROUBLESHOOTING
When installing a cassette, it won't fit onto
the cassette hub.
PROBLEM:
Cassettes fit onto hubs only one way. Inspect
the cassette closely and match its spline to the hub's spline
and it'll slide on.
SOLUTION:
PROBLEM:
The cassette is getting rusty.
SOLUTION: A
little rust won't damage the cogs quickly, so
it's not a major concern. Usually, using a little more lube will
prevent rust, and riding will cause the chain to wear away
the rust while you're pedalling.
PROBLEM:
A tooth or teeth got bent or broken on
a cog.
Usually, it's possible to lever the tooth back into
alignment with a screwdriver. Place it between the damaged
cog and its neighbour, and apply a little bit of leverage to
straighten the tooth. A broken tooth usually won't prevent
the cog from working adequately. If it does, replace it.
SOLUTION:
PROBLEM: Shifting
is not as accurate as it once was.
When you shift, the drivetrain is noisy, as if the chain
isn't quite in gear.
SOLUTION: Check
that the cassette lockring is tight. It may
-lave loosened, allowing the cassette cogs to move slightly
and rattle around on the hub.
PROBLEM: When
you ride an older bike with a freewheel, the freewheel doesn't coast. Instead, it drives
:he pedals around. If you stop pedalling, the chain gets
lunched up, causing a racket.
SOLUTION:
The freewheel has probably rusted inside.
Free it by dripping some oil with penetrating qualities into
:he body
FREEWHEELS AND CASSETTES 137
PROBLEM: Once in a blue moon, you feel and hear
a loud metallic pop coming from the cassette hub or
freewheel body.
PROBLEM: The shifting isn't as precise as it was before
you disassembled and cleaned your freewheel or cassette.
SOLUTION: This is the pawls inside the mechanism slamming into place after getting hung up. If it happens only on
rare occasions, don't worry about it too much. Clean and
relubricate the freewheel or freehub internals. If it becomes
chronic, there may be permanent damage inside the mechanism. In this case, replace the freewheel or the freehub body.
SOLUTION:
PROBLEM:
PROBLEM: The derailleur refuses to shift onto one of
the larger freewheel cogs.
You hear a creaking sound coming from a
SOLUTION: At
rear wheel.
SOLUTION:
Remove the cassette cogs, grease the splines that
the cogs sit on, reinstall the cogs and tighten the lockring.
PROBLEM: When pedalling in certain gears, there's a
disconcerting skipping feeling and sound.
SOLUTION: This occurs when a cog is worn out. If you
have a five-, six- or seven-speed freewheel and individual
replacement cogs are readily available, figure out which is
worn and replace it. Users of seven-, eight-, nine- or tenspeed cassettes may in some cases be able to replace individual cogs or sets of three, but most often this skipping is a
sign that it's too late and the chain and complete cogset will
need to be replaced. Skipping can also be caused by debris
getting jammed between two cogs. For this, clean out the
gunk with a small screwdriver.
PROBLEM:
Check to see that the spacers are installed
correctly and that all of the spacers were reinstalled. There
should be same-size gaps between each pair of cogs. If not,
the shifting won't work correctly.
Pedalling feels crunchy and rough.
SOLUTION: Either the chain has got dirty, or dirt has got
inside the cassette or freewheel bearings. Flush it out with a
light lube such as WD-40, and then apply a medium-weight
oil. Repeat until it runs smoothly.
PROBLEM:
You were going to build a new wheel, so you
cut the spokes out of the wheel, but you forgot to take
the freewheel off first. Now you can't use the hub.
SOLUTION: This
can be tricky. Install the freewheel remover
and clamp the hub (by the remover) in a sturdy bench vice
so that the left flange is pointing up. Wrap a piece of inner
tube around the right-side hub flange (the one closest to the
freewheel) to protect it. Then grab the flange with large
water-pump pliers or a large monkey spanner and turn anticlockwise. If you're lucky, the freewheel will unscrew. Don't
worry about it if you slightly mar the flange.
some point, you may have reversed the
freewheel cog. Most cogs are directional. When installed
backwards, the ramps on the teeth can't pick up the chain
when you shift. Try disassembling the freewheel and
flipping over the cog.
PROBLEM:
When installing a cassette, it fits too tightly
on the hub.
SOLUTION:
Sometimes manufacturers build the cassette
body on the hub slightly oversize because they want the
most amount of purchase for the cogs, which can dig into
the body during pedalling. (This is often the case when the
hub has an aluminium cassette body) To install the cassette,
rubricate the body and gently press the cassette onto the
body. It'll go on if you rock it and work it on gently.
1 38
ILLUSTRATED BICYCLE MAINTENANCE
Basic Cassette and Freewheel
Maintenance
1
Cassette and freewheel maintenance consists basically of cleaning
and lubrication. We recommend that this be done at least monthly.
If you ride in a heavy rainstorm, clean and lubricate both your chain
and cassette or freewheel afterwards.
A thorough job of cleaning is best done with the wheel off the bike. Lift your
chain off the cogs, release the axle and remove the wheel. Lay the wheel
down on a workbench or other flat surface to free your hands for cleaning.
Use a rag to wipe the grease and road grime off the surface of the cogs. You
may want to moisten the rag with solvent, or spray some solvent directly on
the cogs, to help loosen grime. After cleaning the outer surface of the first
cog, hold the rag with both hands. Pull it taut and slide it between successive
cogs, cleaning both sides of each one with a shoe-shine motion.
2
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-
In addition to cleaning the sides of the cogs, make sure you clean the
troughs between adjacent teeth. If you have difficulty getting the cogs
clean with a rag alone, use an old toothbrush or other stiff brush to
loosen the foreign matter, then use the rag to wipe it away (see photo).
Make a special effort to clean the teeth of the cogs as well as you can. When
the chain pulls against those teeth, any gritty matter that is there serves as an
abrasive, causing both the chain and the cogs to wear at a faster rate than
would otherwise be the case. Cleaning the chain and cogs not only prolongs
their life, it improves shifting quality as well.
FREEWHEELS AND CASSETTES 139
3
After you have cleaned the cogs spin the cassette or freewheel around
a few times. If you hear only the familiar sound of the ratcheting mechanism, you can proceed with lubrication. However, if you hear
grinding sounds, you need to clean out this grit. It's usually possible to flush out
foreign matter by dripping oil or some type of solvent through the mechanism.
Don't try to disassemble a freewheel body or cassette body. They're not meant
to be serviced, and replacement parts aren't available. On cassettes, look for
a crack between the outer and inner cassette bodies by spinning the cassette
and watching for where they are separated. Usually, you can find this without
removing the cassette from the hub. Spin freewheels, too, to locate the line
between the outer and inner bodies.
Drip bicycle oil or medium-weight motor oil into the mechanism, spinning the
freewheel to help the oil work its way around (see photo). Put a rag underneath to catch any excess that drains through.
4
......
If your cassette or freewheel still feels or sounds gritty, try flushing
out the foreign matter with the help of a penetrating oil–and-solvent
mixture such as WD-40. Rotate the cassette while you spray the solvent
mixture into it (see photo). Wipe away any excess, then lubricate the cassette
or freewheel once again with oil.
Some people use more potent solvents, such as kerosene. However, after
using such a substance, you may have to oil your cassette several times
before the lubricant is adequately replaced. A penetrating oil should be
able to do the job satisfactorily.
1 40
ILLUSTRATED BICYCLE MAINTENANCE
Cassette Removal and Cassette
Cog Disassembly
1
ro
replace a broken spoke, lubricate the cassette body, change gear
-atios or replace worn cogs, it's necessary to remove the cassette
Tom the rear hub. This is easy to do with the correct tools. For modern
Shimano and Campagnolo cassettes, it requires one chain whip, the appropriate cassette lockring remover and a large adjustable spanner. For older
cassettes (ones without lockrings), two chain whips will do the trick.
Start disassembly by removing the rear wheel from the bike. If it's a modern
Shimano or Campagnolo cassette, you'll see a spline pattern at the centre of
the small cog; this accepts a special lockring remover (see photo).
Unscrew the quick-release mechanism, insert the cassette lockring
remover into the spline and reinstall the quick-release (remove the
lox.v4 springs first) to hold the remover in place. This step, though not crucial,
will prevent the tool from rocking and getting damaged when you apply force.
3
Stand the wheel up, hold it or lean it against something and wrap the
chain section of one chain whip around the largest cog, placing the
handle forwards (in the drive direction). Then place a large adjustable
spanner on the flats of the lockring remover with the handle facing the other
direction (see photo). Hold the chain whip handle and push down on the
adjustable spanner to loosen the lockring.
FREEWHEELS AND CASSETTES 141
4,
Once it's loose, remove the quick-release, and while holding the chain
whip, unscrew the lockring completely, turning the remover by hand.
Once the lockring is removed, the cogs will slide off the hub.
7
If you don't notice splines at the centre of the small cog, you probably
have an older style Shimano cassette system, which doesn't require a
lockring remover. To remove the cogs, stand the wheel up and place
one chain whip on the large cog with the handle facing forward (in the drive
direction) and another on the smallest cog with the handle facing backwards.
Push down on the chain whip on the small cog while holding the freewheel
with the other chain whip to remove the cog (see photo). Once the bottom cog
is off, the rest of the cogs will follow.
Some cassette gear clusters are assembled with bolts or screws (see
photo), or are attached to a carrier, which you'll see when you remove
the gear cluster. In order to separate the cogs on these, it's necessary to
remove the hardware. Just be sure to keep everything in order as you remove it
so that you can reassemble the cogs correctly.
1 42
ILLUSTRATED BICYCLE MAINTENANCE
Freewheel Removal
and Replacement
1
Before you attempt to remove your freewheel, make sure that you
have a removal tool made to fit your particular brand of freewheel.
Begin freewheel removal by taking the rear wheel off the bike.
Thread the axle nut or quick-release skewer nut completely off the freewheel
side of the axle. Slip the removal tool over the axle and into the body of the
freewheel (see photo). Make sure you have good contact between the prongs
or splines on the removal tool and the grooves of the freewheel body. Hold the
tool securely in place by threading the axle nut or inserting the quick-release
and screwing the quick-release skewer nut against it.
co.
Set the wheel upright on the floor with the freewheel facing away from
you. Lean over the wheel and fit a large adjustable spanner on the
spanner flats of the removal tool (see photo). You'll turn the freewheel
anticlockwise to remove it, so fit your spanner on the tool in whatever position
will give you the most leverage - it may take considerable force to break the
freewheel loose from the hub. If you wish to use your right hand, set the
spanner on the right side of the hub so you can push down on it. Flip the wheel
for left-hand work. Grasp the spanner in one hand and steady the wheel with
the other. Push down hard to break the freewheel loose.
3
An alternative to using a spanner for freewheel removal is to lock
the spanner flats of the removal tool in the jaws of a bench vice.
Grab the wheel and twist it in an anticlockwise direction to loosen
the freewheel (see photo).
Mounting a freewheel on a hub is easier than removing one. First, clean
and lubricate both sets of threads. Thread the freewheel carefully on the hub,
beginning in an anticlockwise direction to align the two sets of threads. Reverse
direction and screw the freewheel on as far as you can by hand. Riding the
bike will take care of any further tightening that might be necessary.
FREEWHEELS AND CASSETTES 143
Freewheel Cog Removal
and Replacement
1
With freewheels rapidly falling out of fashion, before buying any tools
or doing any work, check the cogs you want or need to replace are
available. Having the right tools is the key to successful cog removal:
a freewheel vice and at least one, but preferably two, chain whips. To remove
the small, outside cog, immobilize the freewheel in the vice. Fit the chain whip
on the right side of the cog, wrapping the loose length of chain underneath
the cog in a clockwise direction. Push on the handle of the tool to twist the
cog in an anticlockwise direction to loosen it. It is possible to use a second
chain whip in place of a freewheel vice to immobilize the freewheel. In this
case, place the second chain whip on the opposite side of the freewheel from
the firstand wrap it in the opposite direction.
2
...
Try to set up the chain whips in such a way that their handles are
crisscrossed. Then, by squeezing the ends of the two tools together,
you can get the leverage needed to break one cog free (see photo).
When you attempt to remove a cog with a pair of chain whips allow no
more than one cog to separate the two cogs against which pressure is being
applied. The further apart the tools are, the harder it is to channel their force
in the right directions and you risk damaging some cog teeth.
For maximum control and leverage, immobilize the freewheel in a freewheel
vice and use two chain whips.
3
As you begin removing cogs, pay attention to how they come off.
You may find separate spacers between some cogs. Other cogs may
have a built-in spacer protruding from one side. Attention to how the
freewheel comes apart will aid later reassembly. When in doubt, look closely at
the cog teeth. The chamfered (or sloped) side usually faces the spokes. Before
removing the cogs, check the chamfer orientation so you will know the proper
way to put the new ones on. Most likely, you will discover that some cogs have
no threads but are held in place by adjacent cogs. When replacing a cog that
is threaded, hand-tighten it first. Snug it up further with a chain whip, but
expect the cog to tighten fully when you ride on it.
CHAPTER 8
Chains
Chains are all too often mistreated and poorly maintained,
largely due to the common misconception that all you need
to do to take care of your chain is keep it covered in oil. This
practice only furthers the bad reputation chains have for
being dirty, grimy, nasty things that no one would ever want
to touch. Well, it's time to turn this all around.
Caring for your chain is easy — and it gets easier the more
frequently you do it. Better still, a chain that is kept clean and
properly lubricated benefits you and your bike in several
ways. It will shift more smoothly and last longer; it will inflict
less wear on other parts like derailleurs, chainrings and cogs;
and best of all, a clean, properly lubricated chain will work
more efficiently. That means for every pedal stroke, you waste
less energy fighting the chain, so more of it goes into moving
you forwards!
If you like the sound of all this, it's time to start paying
attention to your chain. Before you begin, you should know
what kind of chain you're dealing with.
Chain Identification
There are two common sizes of bicycle chain: X-inch width,
which is used on most BMX bikes and all 1-speed and 3speed bikes; and h2-inch width (also known as derailleur
chain), which is used on all 5-, 6-, 7-, 8-, 9-, 10-, 12-, 15-, 16-,
18-, 21-, 24-, 27- and now 30-speed (!) derailleur bikes. The
width referred to is the thickness of a compatible gear tooth.
The span between the two inner plates of a chain link must,
by necessity, be slightly wider than the teeth that will fit into
the space.
If you can't identify the chain size of your bike from its
type of drivetrain, measure the thickness of one of your bike's
gear teeth. It should be either 342 inch or X inch. If your bike
has a ;<-inch chain, you're all set. If your bike is equipped with
3
/42 (a derailleur chain), you must determine what type.
Chains come in different widths to correspond with different drivetrains and their different numbers of cassette cogs.
If you're replacing a derailleur chain, it's important to correctly identify its type.The easiest way to do so is to count the
number of cogs on the rear cassette. The more cogs, the narrower the chain. Shops will be able to select the appropriate
chain if you can tell them how many cogs are on the cassette
and what type of derailleurs and shifters you have (or just take
your bike in and show them). Pay attention because a rnistake
here will, at the very least, diminish your bike's ability to shift
smoothly. At the worst, it may no longer shift at all.
Standard width. Standard-width chains are no longer standard. They're usually found on older bikes with five or sit)
cogs and they won't work properly on modern 7-, 8-, 9- anc
10-speed drivetrains.
Narrow width. Narrow-width chains are appropriate foi
seven- and eight-speed drivetrains. Complicating matters, the
new 9- and 10-speed drivetrains each take a different ultranarrow chain.The designs are similar, though.The inner links
of most narrow-width chains have slight bulges on their
edges. This is to help counteract the slightly smaller openin g
in the narrow chain that the gear teeth must fit into.
When to Service Chains
There are three common reasons to service a chain: dirt
buildup, poor shifting and component changes.
Dirt can have several harmful effects. Mixed with the oil
often found on chains, it can permanently stain clothing (now
you know why so much bicycle clothing is black). The same
mixture also greatly accelerates chain, cog, chainring and
derailleur-pulley wear. Finally, dirt trapped between chain
links and pins can degrade your bike's shifting ability by
reducing the chain's flexibility.
Worn chain. Do you ever find yourself overshifting your reat
derailleur almost to the next cog to complete rear shifts, and
reducing pedal pressure to finish front shifts? A chain that has
too much lateral, or sideways, flexibility can cause these problems. Although it's often called chain 'stretch', the problem is
not caused by actual lengthening of the chain's steel links but
by wear on the chain pins and bushings. As the chain wears,
or 'stretches', the distance between its chain pins increases.
This condition won't cause problems as long as the sprockets
on which the chain works wear at the same rate.
However, if you're a sensitive rider, you may notice the
changes in performance. Besides slow and imprecise shifting,
a worn chain may make more drivetrain noise when you're
pedalling.You may hear a metallic rattle caused by the parts of
the chain, which have worn and now are loose, vibrating
against each other (although if the chain is heavily lubricated,
it may still run quietly).Also, because the links and rollers have
changed shape due to wear, they do not seat properly on the
cassette cog and chainring teeth. This can cause a rough pedalling feeling. Where once pedalling felt silky-smooth, it now
feels like there's gravel in the drivetrain, and no amount of
ME
1 46
ILLUSTRATED BICYCLE MAINTENANCE
No Missinc Link
CHAINS 147
chain cleaning will restore the smooth pedalling feeling (in
fact, cleaning usually worsens things because it removes the
lube and allows metal-to-metal contact).
When you hear or feel these things, it's time to inspect the
chain closely and replace it if it has become worn.
Usually, chains and cogs wear at the same rate. By the time a
chain is worn out, the most-used cogs have also worn out and
will need to be replaced at the same time as the chain. The
teeth actually take on a slight hook shape, but it's difficult to see
even if you could compare a worn cog side by side with a
brand-new one. Unfortunately, the best test for worn cogs is
test-riding the bike in the cog you think is worn out and pedalling hard to see if the chain skips in that gear.
As a stopgap if you're on a tight budget or can't get to a
shop right away, it's often possible to install a new cassette cog
or chainring and continue using the old chain. It might not
even skip. We don't recommend this, however, because the
worn chain will rapidly wear the chainrings and cogs. (Plus
there's always the danger of a worn chain breaking.) In fact,
one way to get the cogs and chainrings to last as long as possible is to replace the chain regularly, say at the first signs of
wear or every 1,200 to 1,600 km (750 to 1,000 miles). Doing
this prevents the chain from ever having a chance to wear the
cogs past a certain point. Just when the chain is starting to
wear and cut into the cogs and cassettes, you'll install a new
chain, which eliminates the wear because the new rollers and
links are in perfect condition.
Stiff links and skipping. If your bike begins to skip in a gear,
check first to see if the chain is excessively dirty (mud or
sticks stuck between cogs can cause skipping) or has a tight
link. That's a joint in the chain that doesn't bend easily and,
consequently, doesn't run through the rear derailleur or settle
onto the cogs easily. To find a tight link, watch your rear
derailleur's jockey cage closely while you turn the crankset
slowly backwards. A tight link won't lie snugly on the pulleys
and you'll be able to spot it passing through them.
If the drivetrain is clean, there's no tight link and your bike
skips in only one gear, replace the offending cassette cog (it's
worn out). If it skips in more than one gear, weigh the cost of
replacing the individual cogs against the cost of a new cassette.
The cassette as a unit is frequently cheaper than a set of
replacement cogs. If your bike skips in all gears and your drivetrain is old, you need both a new chain and a new cassette.
Even if your bike isn't skipping in any gear, it's worth
checking the chain periodically to make sure that it's still in
good shape. To check a chain, lean the bike against a wall or
some other object that will hold it upright and immobile.
Tension the chain by pressing lightly on the right pedal while
you hold a 300-mm (12-inch) ruler against the top half of the
chain. On any new chain, 12 full links (measuring from pin
to pin) measure exactly 300 mm (12 inches) long. When the
same number of links measures 303 mm (12i inches) or
more, replace the chain.
Chainsuck. This chain glitch occurs on heavily used mountain bikes. It's the annoying tendency of the chain to get sucked
up and jammed between the small chainring and the chainstay. It usually happens when you're trying to shift onto the
small chainring. When it happens, it jams the pedals, forcing
you to stop. Once you experience chainsuck, you won't want
it to happen again.
To prevent this problem from occurring, always use a chain
that's in good condition and keep it clean and lightly lubed.
Replace the small chainring if it's damaged from chainsuck or
if it's worn excessively. Perhaps most importantly, remember
to ease off a bit on pedal pressure when shifting to lower
gears. And if you ever hear or feel a crunching sensation while
shifting, stop pedalling immediately or you'll jam the chain
badly and damage the components, causing a worse chainsuck
problem.
A common cause of chainsuck is mud. As it builds up on
the chain and chainrings, the shifting gets sluggish and eventually chainsuck develops. If you have a water bottle, spray
water at the crank while you're riding. That's sometimes
enough to blast off the mud sufficiently to end the chainsuck.
If you're out of water, find a puddle or creek you can use to
wash the mud out of the drivetrain.
It can be tricky to extract a chain that's got sucked
between the chainring and frame. First try pulling it out, but
don't jerk or twist the links too much.You don't want to bend
the chain or chainring. Sometimes a combination of pulling
the chain and turning the crank will work the chain out. If
these steps don't work, you'll need to either separate the chain
and rejoin it, or remove the crankarm. Both are easy enough
if you have the tools handy.
Don't panic when you see how the chain has scratched the
frame. Usually, it's just nasty looking. If the chain gouged the
metal, remove the right crankarm so you can get at the chainstay. Then lightly sand the damaged area smooth with emery
cloth before repainting the area. The only cause for concern
is if the chain got jammed on a carbon or aluminium frame
and cut into the chainstay. Carbon and aluminium can break
when notched, so this damage could lead to a broken chainstay (worst-case scenario). If you have a carbon or aluminium
frame and the chainstay gets deeply scratched, have the
damage checked by a professional mechanic.
Correct chain length. The final reason for working on a
chain is to achieve correct chain length after component
changes.The changes that may affect chain length include the
replacement of your cassette with one that has a different
range of cogs, the installation of a wider-range or triplechainring crankset and a change in rear derailleurs.
148 ILLUSTRATED BICYCLE MAINTENANCE
A general rule for chain length is that there should be
enough chain to permit shifting onto the largest cassette cog
while also on the largest chainring. This will prevent damage
to the derailleurs if you unintentionally shift into this normally unused combination. With a triple crankset that has a
`granny', or small inner chainring, the derailleur may double
over onto itself when your chain is on the smallest chainring
and any of the outer, or smaller, freewheel cogs. However, it's
considered acceptable practice to use the granny chainring
only with the three to five largest inner freewheel cogs. In
those positions, the rear derailleur shouldn't double over.
Modifying chain length provides you with the opportunity
to use those seemingly useless scraps of chain that were left
over from your last chain installation. Don't throw away any
short lengths of new or usable chain until you have a substantial collection. You never know when you're going to
need to lengthen a chain or replace a tight, damaged or
broken link. Smart mountain bikers and touring cyclists carry
a few links and a chain tool along on rides — if you have a
chain mishap far from help, you usually have to repair only
one or two links, not an entire chain.
Separating a 1/8-Inch Chain to Remove it
If your bike has a Y-inch chain, that chain can be disconnected, or 'broken', at its special master link.This link is fatter
than the others and you can usually find it by watching
closely for it while pedalling. There are two types. One has a
spring clip (it looks like an elongated horseshoe) holding the
link together. On the other, the link is held together by the
pins, which have notches in them.
If the master link is the clip type, use a small screwdriver
or a pair of needle-nose pliers to pry off the spring clip, then
pull off the outer link on that side of the chain. Slide either
end of the chain off one of the exposed pins of the master
link. Reverse the procedure to put the link together.
Coaster brake and three-speed bikes have chains that are connected at a
master link, a special link that can be disassembled for removing the chain.
There are two types. One is opened by flexing the chain and lifting off the
sideplate; the other (see photo) is removed after prying off a spring clip.
Chains are separated and put together with chain rivet or chain pin
extractors (commonly known as chain tools).
If the master link is the pin type, simply bend the chain
sideways at this link to close the pins slightly. In this position,
the inner plate of the link will slip off the ends of the pins,
allowing the chain to be separated.You may have to loosen
the rear wheel of the bike to get the slack you need to give
the chain lateral flex. Otherwise, it's a simple and quick procedure. Replace the plate in the same manner you took it off.
Separating a %2-Inch Chain to Remove it
The fatter master link found on single- and 3-speed bikes
would create problems if found on a 3/32-inch, or derailleur,
chain. It would lead to chain snags on the front derailleur cage
and the rear derailleur pulley. That's why master links have
traditionally not been used on these chains.
In order to separate and reassemble a 3A2-inch chain, you'll
probably need what is commonly referred to as a chain tool.
Buy an inexpensive, screw-type chain tool for at-home maintenance — and consider carrying one on rides. Certain chain
types are easier to service with particular tools. Make sure that
the chain tool you purchase is compatible with the type of
chain on your bike. A bike shop or tool supplier should be
able to advise you if you tell him what type of chain you're
working on.
All current Shimano chains and Campagnolo 9- and 10speed chains require a special replacement pin for reassembly.
To remove these chains, press a pin completely out. When it's
reassembled, insert the new Shimano pin until it clicks, and
break off the end that protrudes by bending it sideways with
a pair of pliers.
For other derailleur chains, it's important not to push the
pin all the way out of the link, because doing so will make
CHAINS 149
Certain derailleur chains have special connecting links (such as the SRAM
Power Connector chain shown here) that make chain installation and
removal easier because you can do it by hand.
reassembly difficult. When pressing the pin with the chain
tool, the object is to have the inside end (the end nearest the
bike) of the pin protrude a little on the inside of the outer
plate of the link (the plate nearest you when you face the
chain). If you're using a screw-type chain tool (there are also
plier-type tools), take the time to unscrew the tool and periodically check progress before you've gone too far and
pressed the pin all the way out. If you do it right, you will
have to grab the chain on either side of the link you're separating and bend it a little to wedge the link apart. The little
bit of pin that is still in the link will help hold the two ends
of the chain together while you get the chain tool aligned to
press the pin back in.
If you do extract the pin all the way, a trick to help reconnect the links more easily is to get a Shimano special replacement pin, put that in to hold the chain ends together and then
push the original pin back in. Otherwise, if you can't get the
pin in, remove that link and the one next to it and replace
them with another pair. Press the new pin out the way you
wanted to do on the first one, and replace the damaged link
from your supply of extra links.
Quick Connectors
Chain tools do their job well enough if they are used carefully. Still, the job of separating a derailleur chain is a lot easier
if it has a master link. SRAM's Power Connector chains
include just such a link. These special links are easy to spot
because they look different than the other links on the chain.
The SRAM Power Connector comes apart by pinching the
side plates inward, and then sliding the pins towards each
other. The force of pull on the chain makes it impossible for
these quick connectors to separate unintentionally. _
Cleaning and Lubrication
Sometimes it seems that every mechanic has a different idea
of what is the best way to clean and lubricate a chain. But all
would agree, I think, that the key words are 'lightly and frequently'.This simply means that it's better to wipe your chain
down and apply a little lubricant every few rides than it is to
soak the chain in oil a couple times a year.
Unless your chain is equipped with a quick connector,
think twice about removing it to clean it. If it's not too grimy,
it's easy to clean the chain while it's still on the hike by wiping
it with a rag moistened with solvent. Spray a few links at a
time with solvent to loosen the grime. Put on gloves to protect your hands, then wipe off the gunk on the sideplates and
rollers and repeat until all the links are clean.
This is the best way to clean mountain bike chains and Sand 10-speed road chains because removing and reinstalling
them can lead to weakening the links and worse — possible
chain breakage when you're riding. If you wipe the chain regularly, it'll also reduce the amount of grime buildup on the
cassette and chainrings.
The other thing to consider is how worn the chain is. It's
always best to measure a chain before cleaning it, as there's no
sense in cleaning a worn-out chain. Replace it instead.
If the chain is in good condition but is so filthy that you
feel you must remove it for cleaning, take it off and immerse
it in a solvent, such as a commercial degreasing/cleaning fluid
or kerosene (put rubber gloves and goggles on first for protection). Pour enough solvent into a container (a 2-litre
plastic bottle is handy because it'll keep the fumes down and
you can shake it to clean the chain) to cover the chain.
If the chain is particularly dirty, let it soak for a while to
allow the worst of the dirt to float off.Then carefully pour off
the upper, cleaner layers of solvent into another container and
leave the grit from your chain behind. Transfer your chain
into the container with the clean solvent and brush it clean.
When you're done cleaning with the solvent and brush, dry
the chain thoroughly with an old rag and hang it somewhere
to dry. Don't try to lubricate the chain until all of the cleaning
solvent has evaporated.
There are varied opinions of what is the best lubricant.
Some prefer dry lubes that consist of a light lubricant in a
volatile carrier, which are usually applied from an aerosol can.
Because they end up dry to the touch, these lubricants attract
a lot less road dirt than lubricants such as motor oil, which
remain moist. After cleaning the chain and allowing it to dry,
apply one of these specialized lubricants to reduce dirt pickup
• usricating • • - - .
on the chain while maintaining
e type of spray lubricants to help
You can also use • minimize t number of times you have to remove your
cha fes cleaning. Every few rides (depending on the condi-dons), spray a wet coat of lubricant on the chain and wipe
away the excess and whatever dirt you can. From time to
time, you will still need to thoroughly clean and relubricate
your chain or replace it, but this type of treatment can help
you stretch out the time between major cleanings.
Also popular today are wax-based lubes that are applied
and left to dry. These need more frequent application but are
1 50
ILLUSTRATED BICYCLE MAINTENANCE
Loosen stiff links by holding the chain in your hands and flexing it back and
forth and sideways. This should work on a newly installed chain. If the tight
link is on an older chain, especially one that's rusty, you may have to replace
the bad section with a new section.
among the cleanest lubes available. They're not the best for
wet riding, but they work well in dry climates.
Of course, there are also those who prefer using oil on
chains. It's only natural. Oils do a better job of fighting corrosion and don't wash away when wet, making them a good
choice for early spring or for rainy climates.
Because there are so many types of lubricants designed for
different uses (new ones come along almost monthly), you
may want to experiment to find the best one for the type of
riding you do and the climate you ride in. For advice, ask
local shop mechanics or friends you ride with.
Sometimes, after a thorough cleaning with a potent
solvent, a chain will squeak even after a light lube has been
applied.To stop the squeak, apply a light coat of bicycle oil or
an oil-based chain lubricant to the chain. Wipe it as clean
as possible and then maintain the chain with your spray,
nonaerosol drip or wax lubricant.
Whatever you do, don't use three-in-one oil: it's vegetablebased, which means it will gum up your chain, and it doesn't
protect against wear nearly as well as a lubricant that is
mineral-oil based.
Reassembling a Chain
When installing a chain, don't place it on the chainring, but
be sure it passes through the front derailleur and rear
derailleur cages correctly. Leaving it off the chainring during
installation will provide slack in the chain, which makes
aligning the ends easier.
If you're putting together any modern Shimano chain or a
Campagnolo 9- or 10-speed chain, you must have the special
replacement pin. Both work in a similar way. Align the ends
of the chain, start the pointed guide end of the pin in by hand
(for Shimano, the guide is integrated; for Campagnolo, the
guide is a separate piece), put the chain tool in place and turn
the handle until the pin is seated. You should hear or feel a
slight click when the pin is fully inserted. Remove the tool
and remove the guide.You will need to break the guide off of
a Shimano pin with a pair of pliers, or you can just insert it
in the end of the chain tool and twist.
To install other types of chains, run the end of the chain
that does not have the pin sticking out (remember, the pin
should protrude towards your side of the bike) through the
rear derailleur cage, over the freewheel, through the front
derailleur cage (but not over the chainring teeth), around the
bottom bracket and back to the other end of the chain. If you
do place the chain over the chainring at this point, there will
be tension in the chain and you may find it difficult to keep
the two ends of the chain together while you attempt to
rejoin them.
Wedge the inner-link end of the chain into the outer link.
The little bit of pin protruding inside the outer link should
hold the two ends together. Use your chain tool to press the
pin back through the links until the pin protrudes equally
from each side of the outer link.
Usually, a chain will be tight at the newly rejoined link.
There are two ways to free it. First, if your chain tool has an
alternate position for holding the chain, unscrew the tool
enough to move the chain into the other position so the
chain will be held in place by its inner link instead of by its
outer one. That means that if you press on the pin just a little
more, the outer link will be free to move away from the inner
link, freeing the chain.
The second, cruder method involves grabbing the chain
firmly on either side of the tight link and bending it sideways,
back and forth, a few times. If the link doesn't free up, bend
the chain again a little harder. Don't overdo it or you may
permanently bend the chain.
Once your chain is back on your bike, take the time to
wipe it off occasionally and lubricate it when it starts to look
`dry'. Regular preventive maintenance will reduce the
number of times you have to go to the trouble of a major
cleanup. It will also help you maintain good shifting and minimize the number of chain stripes you end up wearing. Once
you discover how pleasant it is to ride with clean, smoothrunning chain, you'll never take this valuable part of your bike
for granted again.
CHAINS 151
TROUBLESHOOTING
PROBLEM:
The chain is always a black, grimy mess.
SOLUTION:
PROBLEM:
The chain runs noisily.
If the chain is lubed and not worn, it's probably
a derailleur adjustment problem.
SOLUTION:
Clean it, using less lube or a lighter lube.
PROBLEM:
The chain breaks on a trail and you don't
have a tool to fix it.
The chain falls off all the time.
PROBLEM:
SOLUTION: Find a piece of wire (from a fence maybe) or
string (use a shoelace if you have one) and tie the chain ends
together. Then pedal gently (walk up hills) and you ought to
be able to 'limp' home.
The chain squeaks when you pedal, even
though you've lubed it.
PROBLEM:
SOLUTION: Try
a lube with better penetrating qualities.
After applying it, let it sit a bit. Be sure to wipe off excess
lube because it will attract dirt.
PROBLEM:
When you pedal hard, the chain skips.
If it skips on only one cog, it's probably a
worn-out cog. Replace it. If the chain skips on all or most
of the cogs, it's a tight link. Find it by pedalling backwards
and watching for it to bind as it passes through the derailleur
pulleys. Then flex the chain sideways to free the link. If the
link is rusted tight, replace it. Replace the chain if there are
several stiff links in different locations.
SOLUTION:
PROBLEM:
The chain runs roughly when you pedal.
Replace it if it's worn out, or try a different
model of chain if yours is relatively new but it runs roughly.
Some chains run more smoothly than others. It may also be
a worn chainring (if the teeth are smallish and hook-shaped,
it's worn).
SOLUTION:
PROBLEM: While you're shifting your mountain bike,
the chain gets sucked up and jams between the chainring and frame.
SOLUTION: This
is called chainsuck. Keeping the chain
clean and lubed helps prevent this. It's also crucial to shift
with light pedal pressure. When chainsuck is chronic, it's
often necessary to replace the chainring.
If you get the chain stuck, try pulling it out.You may
need to turn the crank while pulling on the chain. If this
doesn't work, either remove the crankarm or separate the
chain to get the chain out.
SOLUTION:
This is usually a derailleur adj ustment problem.
PROBLEM: When you shift, the chain gets jammed
between the chainrings.
Make sure that the chain is the right width for
the drivetrain. If it is, check the chainring bolts for tightness.
Make sure that the chainrings are straight. Check the
spacing of the chainrings. Replace any worn chainrings.
SOLUTION:
1 52
ILLUSTRATED BICYCLE MAINTENANCE
Chain Maintenance
and Repair
Frequently clean and lube a chain to keep it operating well. Especially
after it has been subjected to muddy water. Modern mountain bike
chains and ultra-narrow 9- and 10-speed road chains are best cleaned
on the bike; moisten a rag with solvent and wipe the chain clean weekly.
Since many chains found on derailleur bikes are not equipped with master
links (there are exceptions; see page 149), the customary method of removal
involves the use of a special tool to separate a link. To separate a chain, slip it
off the front chainring to remove tension from the chain. Wind the centre rod
of the chain tool back far enough for a link of chain to slip into the slot provided for it, then screw the rod forwards against the pin (see photo).
Make sure that the rod and pin are properly aligned, then continue to
wind the rod forwards to push out the pin. When the pin appears to
hew– be most of the way out of the link, remove the tool and see if the link
can be separated. If not, replace the tool and drive the pin further out. Be
careful: stop when the pin end against which you are pushing is still visible on
the inside of the outer plate (see photo). A pin that is pushed all the way out of
a chain link can be put back in, but the process is so difficult that it's simpler
to move the tool to the next pin and work on it, completely removing and
discarding the first link. The exception is Shimano's modern chain. On this,
the pin must be pushed all the way out, and after cleaning is finished, the
chain is rejoined with a special hardened steel pin made for the purpose.
3
After separating the chain, pull it off the front and rear sprockets and
soak it in a can of solvent (or put it in a plastic soda bottle with some
solvent and shake it up). Once the grease and grime have begun to
loosen, use a brush to clean inside the bearing areas (see photo). Wipe off the
chain with a clean rag and hang it up until all the solvent has evaporated, then
reassemble it on the bike, making sure to run it through the front and rear
derailleur cages (but don't put it on the chainring yet). Align the ends and use
the chain tool to force the pin back in. If it's the Shimano or Campagnolo special pin, it will make a slight clicking sound when it's seated, and you'll need to
remove the guide end of the pin (break it off with pliers if it is a Shimano version). If the rejoined link is stiff, flex it back and forth sideways to loosen it.
CHAINS 153
4
Using a drip bottle of your favourite lube, or an oil can or aerosol
spray can with a thin nozzle, direct some lubricant into the bearing
areas of each link (see photo). When the entire chain has been lubri-
:ated, wipe off the excess with a clean rag. Oil left on the surface of the chain
will only attract more dirt. If you favour a wax-based or dry lubricant like
)edro's Ice Wax or Finish Line Krytech, don't wipe it off. Allow it to dry fully
)efore you ride.
....
Chains on children's bikes and three-speed bikes have master links
that make removal fairly simple. One type of master link has a clip
that must be pried loose with a screwdriver. The other type has a plate
field between two special grooved pins. To remove it, you simply bend the
hain sideways to move the tips of those two pins closer together.
6
MOP
'11M1k4
MIMI
Once the plate is out of the grooves, it can be slipped off by hand. The
link then comes apart easily, and fastens back together just as easily.
CHAPTER 9 All
Shift Levers
The shift levers are the means by which you connect with the
Ile levers are simply tight enough that they can resist the
variable gearing of your bicycle. On a road bike, the shift
ension of the springs and hold the derailleurs in whatever
;ear you have selected. This tension resistance is sometimes
levers are most often mounted on one of three different locations: the down tube on the frame, the stem or the handlebar.
lone by means of a special ratcheting system.
In the last decade or so, the handlebar has become the most
common location for the shifters, emphasizing convenience
ihift Lever Locations
['he most desirable road bike shifter among enthusiasts is the
and control.
Shimano, Campagnolo and Modolo all offer road shift
ombination brake-and-shift lever (commonly referred to as
brake-shifter) because it allows shifting while climbing and
levers built into the brake levers. For mountain bikes, shift
levers are always mounted on the handlebars — near enough
printing. In fact, any time the hands are near the brake levers,
to the hand grips that gears
is possible to shift by pushing sideways on the brake levers or
can be shifted with
mall built-in toggles. This ingenious design makes it so easy
the thumbs and/or
o shift that you actually shift more often, which helps keep
forefingers
while
your legs fresh on long rides. Manufactured by Shimano,
your hands remain on
Campagnolo and Modolo, the dual-purpose levers are
the bars. This is certainly
complicated, expensive and heavier than down-tube levers
but provide too much of a shifting advantage
most appreciated when the going is
rough and removing a hand from
for many serious riders to pass
them up. They now come as
the grip might result in an 'off-thestandard with most compobike' experience. Also in common
nent groups, though you can
use on mountain bikes are twist-grip
sometimes request that the
shifters, such as those made by
company substitute down-tube or barSRAM. Twist shifters replace a short
end levers. (But why would you want to?)
section of the grip so your hands are
For a long time, the down tube was the
always in place on the shifter, ready to
standard position for the lever on dropped
make a shift. Three-speed bicycles use a
type of shifter that has three distinct
handlebar bikes. To shift, you reach down
Twist shifters like SRAM Grip Shift are light and
to the lever. To some degree, this would
positions — the first indexed shifter.
Despite differences in size, shape and simple. With a turn of the wrist, a rider can shift lower your centre of gravity, maintaining
location, all shift levers have much in through several gears at a time, as compared to stability while you have a hand off the
bar. Also, the cable runs are short and
common. On a three-speed bike, the lever-type shifters that sometimes only allow a
gear or two to change with each press of a lever.
direct, resulting in very fast shifts. Moresingle shift lever is connected by cable
over, many down-tube shift levers are
to a gear system housed inside the rear
hub. Bikes of five speeds or more have one or two shift levers, designed to mount on braze-on bosses. These fittings are
each connected by cable to a derailleur. Moving these shift actually part of the frame and can't slip or break like ordinary
levers back and forth tensions or relaxes the cables, moving band clamps. The bosses give the frame a clean look.
Handlebar-end (also called bar-end) shifters are a favourite
the derailleurs so that they can shift the chain from one
cog or chainring to another to produce the various gears of of long-distance tourists. Their positioning at the ends of a
drop handlebar is nearly as convenient as integrated brakethe bike.
Because derailleurs are spring-loaded, they will always shifters. Their real draw, though, is that they retain the ability
move quickly to the most relaxed position unless restrained to switch between indexed mode and friction. In the case of
by the shift levers. Thus, shift levers on modern derailleur a topple or other situation affecting the rear derailleur's ability
bikes have a set position and the lever is 'clicked' into each to accurately index from cog to cog, a simple twist of a
gear. Older bikes with down-tube shifters may be equipped D-ring puts the shifter into friction mode so the rider can
with levers that do not click but are held in place by friction. make fine adjustments until a permanent repair can be made.
SHIFT LEVERS 1 57
111■1
There are several types of mountain bike shifters.
Thumb-operated shift levers are available, which attach to
the top of the handlebar (old style) or under it (modern
style). There are also popular shifters made by SRAM that
are twisted-throttle style. The top-mounted shifters are
simple, having only one lever on each side that moves forward and back to shift gears. Under-the-bar shifters use dual
levers: one for upshifts, and another for downshifts. Some
designs take two-finger operation: you push one lever with
your thumb to shift to a larger cog or chainring and the
other lever with your forefinger to move the chain to a
smaller cog or ring. Although below-bar levers are a little
more complicated to repair and are heavier than above-bar
levers, they're pretty much standard now because they shift
more quickly than above-bar models and allow you to keep
a better grip on the bar during shifts.
The latest innovation from Shimano is integrated brakeshift levers for mountain bikes. The lever moves in three
directions: pulling towards the handlebar pulls the brake
cable, pushing the lever downwards with the fingertips pulls
the gear cable and flipping the lever upwards with the backs
of your fingers releases cable.
Twist shifters are light and simple, containing fewer parts
than modern lever-type shifters. Lots of mountain bikers and
casual cyclists like them because they allow shifting with a
full-fingered grip on the handlebar. Twisters can also be
shifted through several gears with a single twist of the wrist,
rather than several clicks of a lever or trigger.
As with all things, deciding which type of lever is right for
you is a matter of personal taste.Try out all the different styles
you can wrap your fingers around, and don't dismiss anything
based solely on someone else's opinion. You may not know
what you're missing.
Factors That Affect Lever Performance
Most shift levers are designed to work as a set manufactured
by the same company; the set includes the front derailleur, the
rear derailleur and the two shift levers. You should try to
maintain these sets. If you change to a different type of lever,
it may negatively affect the way your derailleurs shift.
Shift levers do not ordinarily require much maintenance.
The most common problem people have with them is
allowing them to loosen and then losing parts. Sometimes the
`clicks' of levers become less distinct.This is usually because the
parts inside are dirty or worn.A good cleaning and lubrication
may help. If the clicks still aren't crisp, small internal parts may
be worn. One indication of this is when an otherwise welladjusted system lands between gears frequently. In severe cases,
the lever may be incapable of moving the chain to certain
gears. Generally speaking, worn levers should be replaced,
although on some models you can purchase replacement parts
directly from the manufacturer.
Integrated brake-shift levers like these from Shimano (right) and Campagnolo
(left) keep all braking and shifting duties close at hand. Because systems like
these have made shifting so convenient, you end up shifting more often, conserving energy on long rides.
Expect your levers to shift poorly if they are mismatched
to the derailleurs or if they are of poor quality. No amount of
servicing will remedy these problems. Replacement is the
best solution.
Removing Shift Levers
Most shift levers are held on either the stem, down tube or
handlebar of the bike by removable or built-in clamps, or they
are fastened to braze-on bosses on the down tube. The
removal method is similar for all these levers.
First, cut the cable end caps off if there are any, and release
the shift cables from the front and rear derailleurs by loosening the cable anchor bolts on both.
Road bike clamp-on stem or down-tube levers. If the levers
are clamped on the bike, loosen and remove the clamp nut and
bolt. Gently bend the clamp wide enough to clear the down
tube or the stem, and remove the lever unit.
For clamp-on and braze-on levers, use a screwdriver — or
your fingers, if the tensioning bolt has a D-ring to grip — and
loosen the tensioning bolt.The tensioning bolt is the part that
holds the lever in place on the clamp. Gently wiggle the shift
lever and pull outward, until it and the washers on both sides
of the lever come off the fitting or the braze-on boss,
depending on the way it is mounted. Make either mental or
written notes on the order of the parts so you will be able to
put the lever back together later.
Road bike handlebar-end shifters (Shimano/Campagnolo/
SunTour). Release the shift cables from the front and rear
derailleurs by loosening the cable anchor bolts on both.
On one side of the friction shift-lever body (the part
sticking out from the end of the bar), there is a wide screwdriver slot in a cap-locknut. Insert a screwdriver and unscrew
the cap. You'll see a recessed nut beneath the cap. Once the
;
1 58
ILLUSTRATED BICYCLE MAINTENANCE
cap is removed, unscrew the screw on the other side of the
lever, then pull the shift lever away from the body. Remove
the lever by pulling the cable all the way out of the housing.
Index bar-end shift levers are attached with screws. On the
right Shimano index levers, there's a D-ring that changes the
lever from index to friction mode. Unscrew the centre screw
(the D-ring is attached to a ring outside it) with a screwdriver
to remove the lever. For the left, the screw may have a D-ring
directly attached — remove it either with a screwdriver or by
hand, as appropriate.
Once the shift lever has been removed, you can remove the
body. Inside the body, you will see a 6 mm hex bolt. Insert a
hex key and turn it clockwise. After one or two turns, the
expander should be loose enough for you to pull the lever
body out of the handlebars.
Mountain bikers have a choice in ways to change gears. Grip Shift are the
ultimate in simplicity and reliability. Triggers guide your chain with the push
Road bike brake-lever shift levers (Shimano STI/Campagnolo Ergopower). The inner workings of brake-shift levers
can be incredibly complex. Shimano does not offer replacement parts for their shift mechanisms, so their brake shifters
must be replaced when they fail. Campagnolo and SRAM
both offer service parts, but performing a rebuild of a brakeshifter is tricky business, so it may be best left to a pro. It's
fairly easy, however, to remove them from the handlebar
should you need to replace a damaged lever or bar, and it's
pretty easy to replace cables.
To remove the levers, unwrap the handlebar tape and loosen
the 5 mm hex clamping bolts located on the sides of the lever
bodies (look beneath the rubber hoods to find the bolts). This
will loosen the clamps and allow you to slide the levers off the
bar (it's unnecessary to remove the cables to do this).
To remove the shift cables, cut off the aluminium end caps
(if there are any), click the shifter to its 'normal' position
(cable fully released) and loosen the anchor bolts on the front
and rear derailleurs. The cables wrap around the shifting
mechanism inside the lever. To find the ends, push the cables
towards the lever. You may need to squeeze the brake levers
to open them slightly and operate the shift lever to move the
shifter into a position where the ends of the cable will come
free, allowing you to extract the cables.
Internal gear hub three-speed thumb shifters (Sturmey
Archer/Shimano).Three-speed thumb shifters are very simple
to work with. If they don't work, replace them; there are no
user-serviceable parts inside. Replace the cable by releasing it
at the hub, freeing its upper end from the catch in the lever
and pulling it out.You may have to use a small screwdriver to
lift a catch plate on the lever in order to do this. To reinstall
the component, follow the removal steps in reverse order.
Mountain bike shifters (Shimano/SRAM/ SunTour). There
are many kinds of mountain bike shifters, and the exact
of a thumb or the tap of a forefinger. Shimano's STI shifters combine shifting
and braking duties in a single, multidirectional lever blade.
construction varies from manufacturer to manufacturer. Most
types, including above- and under-bar thumb levers and twist
shifts, are held on with a clamp that is loosened by turning a
nut and bolt or a single hex bolt. Of course, to remove the
lever from the bars, you must first remove the grips (and
sometimes the brake levers).
One notable exception you might run into is an older
above-bar thumb shifter model made by SunTour. For this
model, you must remove the lever to get at the nut.The lever
is removed by unscrewing the tension bolt on top. Once the
lever is off, the clamp can be removed or repositioned.
To reinstall mountain bike levers, follow the removal steps
in reverse order.
Servicing Shift Levers
As we discussed, Shimano Rapidfire shifters and STI brakeshift levers, whether for road or mountain bikes, cannot be
serviced. They're designed to be replaced when they fail.
Campagnolo Ergopower and SRAM Trigger shifters can be
rebuilt and repaired by a qualified mechanic, but it's not a task
to enter into lightly. All other lever types can be serviced by
the home mechanic to one degree or another.
Road bike down-tube levers. Start by taking the lever apart
and cleaning all its parts with a safe solvent. When working
with index levers, do not completely dismantle the small parts
inside unless they separate on their own. Most have factoryassembled inserts that are not designed for user servicing, and
they won't work properly if this piece is misassembled. Make
a note of the order of the parts as you remove them. Use
alcohol on any parts made of plastic. Alcohol may be adequate
for the metal parts as well. Allow all parts to dry before
reassembling the lever.
SHIFT LEVERS 159
If index levers still don't function after cleaning and
reassembly, something inside is probably worn out or damaged. In that case, it's best to replace them. Usually, shift levers
are sold in pairs.
When you reassemble the shift lever, only the metal-tometal surfaces need lubrication. The nylon washers used in
shift levers are normally self-lubricating, and grease or oil will
make them too slippery. Remember, the main purpose of
these washers is to generate friction, so you don't want them
to be too slick.
If you're working on an older friction lever that slips all the
time, you may need to replace its washers. Check with your
local bike shop to see if washers for your particular lever
are available.
If you can't find new washers, there are a few things you
can do to make the old ones work better. To start with, turn
the washer upside down and see if it works better that way.
You can also rough up the surface of the washer with sandpaper to eliminate some of its slickness. Finally, you can fit an
ordinary flat washer over the old washer.
Mountain bike twist-grip shifters. Usually, the cause of slow
shifting is contamination in the cable and housing due to dirt
that's got inside or corrosion caused by water running down
the cable and entering the housing. Check the cable and
housing first. Try lubricating it, or replace the cable and
housing if necessary. If the shifter is still difficult to turn or
doesn't work properly, it probably needs cleaning and lubrication.
When working with twist shifters, it's important to use
only Tubes and cleaners that will not damage plastic and
rubber. Specifically, avoid petroleum- or citrus-based solvents.
Products like Pedro's Bio Cleaner are safe for plastics. In the
absence of a plastic-safe specialized cleaner, alcohol or a solution of dishwashing detergent and warm water work well.
There are only a few lubricants that are factory-approved for
use in plastic shifters like SRAM's Grip Shift shifters. SRAM
Jonnisnot or Finish Line's Grip Shift approved grease are the
most widely available. Do not clean the shifters with highpressure spray systems, such as those found at a car wash,
because these can damage the parts and may worsen shifting
by forcing dirt into shifters.
To clean twist shifters, disassemble them. Open older
models by pulling outwards to separate the twist grip from
the shifter body, allowing access to the inside parts (move the
grips or slide over the brake lever first). If the shifter doesn't
open, try rotating it away from you fully first, or remove the
triangular plastic cap by the cable adjuster and try again.
SRAM's newest models are a little more complex inside
and require a few more steps to disassemble and clean than
older versions. The necessary techniques are detailed, with
photos, on page 168.
When the shifter is open, wipe the interior clean with a
rag or a cotton swab. If the insides are really dirty, clean them
first with warm water and dishwashing detergent. Then let
the parts air-dry, apply approved grease and reassemble the
shifter, being careful to locate the parts correctly.
Installing Shift Levers
How you install your shift levers is largely dependent on what
type of shift levers you've chosen to suit your bike and your
needs. This is especially so on road bikes.
Road bike braze-on levers. Gently slide the shift lever and
the associated washers back on the bosses in the same order
in which they were removed and retighten the tensioning
bolt. Reroute the shift cables to the front and rear derailleurs
and tighten the cable anchor bolt on each. If you are installing
new cables, shift the levers several times, then recheck the
cable tension. If the cables stretch, loosen the anchor bolts,
take up the slack and retighten them.
Road bike clamp-on stem or down-tube levers. If you are
replacing an old lever, reassemble the lever parts on the clamp
in the same order in which they were removed. Gently bend
the clamp wide enough to slide it around the down tube or
the stem.Insert and tighten the clamp nut and bolt on the
stem or the down tube. Position a stem-mounted shifter so
that the tops of the levers are just a bit higher than the top of
the stem. Position down-tube shifters so that they sit at the
point your hand naturally falls when you are sitting on the
bicycle. Some frames have a stop to prevent the shifter from
slipping down the frame. If you have one of these, use it.
Reattach the shift cables to the front and rear derailleurs by
pulling each cable taut and tightening the cable anchor bolt
on each. If you are installing new derailleur cables, shift the
levers several times, then recheck the cable tension. If the
cables have stretched, take up the slack and retighten them.
Handlebar-end shifters. If you are installing handlebar-end
shifters for the first time, you will also have to install the cable
housing. There are two ways to route the cable housing: with
a loop and without. In the first case the cable housings run
from the bar-end shifter along the bottom of the bar until the
bar turns up towards the brake lever. Here, the cable stops following the bar and loops out and around to the cable stop on
the down tube. In the second, the cable housings follow the
shape of the bar, staying under the tape until an inch or two
before the stem, and then loop down to the clamp on the
down tube.
Both gear cable routes require that you wrap the handlebar
tape after the cable has been run. Hold the cable housing in
place with a piece or two of electrical tape to make it easy to
wrap the handlebars.
1 60
ILLUSTRATED BICYCLE MAINTENANCE
When you are ready to install the shifter, insert the shifter
body into the handlebar end and tighten the expander with a
6 mm hex key. Make sure that the body is oriented so that the
lever moves vertically rather than off at some odd angle.
If the cable housing has not already been installed, install it
now so that the opening of the housing lines up with the hole
in the housing stop on the body of the shifter.
When both the shifter body and the cable housing are
attached to the bar, run the cable through the shift lever, then
through the hole in the body and through the cable housing.
Fit the lever in place on the shifter body and bolt it in place.
Friction levers are held on the body with a bolt and nut. The
bolt passes through the body and lever and threads into a nut
on the other side. On most models, the nut fits in a recess on
the side of the body. There is a round, slotted locknut that
should be tightened over the recessed nut to hold it in place.
Shimano index levers are held on by screws. Tighten the
right lever into place by turning the screw in the centre of the
D-ring. The left lever is held in place by a screw that may
either take a screwdriver to tighten or have a D-ring attached,
allowing it to be tightened by hand.
Route the cables to the front and rear derailleurs. Run the
cable ends through the anchor bolts, pull them taut and
tighten the nuts to hold them secure. If you are installing new
cables, shift the levers several times to stretch them, then
check the cable tension. If the cables stretch, loosen the
anchor nuts, pull them taut again and reanchor them.
Road bike brake-shift levers. Like handlebar-end shifters,
brake-shift levers use long cables and housings. These attach
in two different ways, depending on which brand you have.
Shimano STI models use housing sections that run directly
from the brake lever bodies to the down-tube stops. The
housing sections are not wrapped under the bar tape, which
simplifies housing replacement and lever installation.
Campagnolo Ergopower levers use housing sections that
are wrapped under the handlebar tape. This gives the bike a
cleaner look and shields the housing from wear.
Since brake-lever shift levers also operate the brakes, the
brake cables should be hooked up before installing the levers
on the handlebar (for advice on this procedure, see page 236).
Once this is done, hook up the shift cables and housings.
Start by shifting the right return button at least ten times, and
the left three times. For Campagnolo levers, push down on
the buttons located on the inside faces of the brake lever
bodies. For Shimano models, push the smaller levers (located
behind the main levers) to the inside. Also, shift the chain into
the small freewheel cog/small chainring combination.
Now you can install the cables. Once they're in place, pull
them taut and tighten the derailleur anchor bolts. If you have
installed new derailleur cables, shift the levers several times
and then tighten the cables if you've created slack.
TROUBLESHOOTING
PROBLEM: The bike suddenly shifts on its own into
a harder gear.
SOLUTION: This
happens on older-style shift levers that
don't click into gear. Look for a D-ring or screw to tighten
(turn clockwise) on the side or top of the lever. That will
increase friction and after a shift the lever will stay where
you put it.
After installing a new cable, the shift lever
doesn't click the derailleur into gear as it should.
PROBLEM:
Loosen the cable anchor bolt on the derailleur.
Pedal by hand to shift the derailleur to the smallest cog or
chainring, and make sure the shift lever is in its starting
position. Then reattach the cable.
SOLUTION:
PROBLEM: A
shift cable breaks while riding.
SOLUTION: Try
to tie a knot in the remaining cable so that
it holds the bike in an easy gear so you can ride home. Or,
if you have down-tube shift levers and a few inches of cable
protruding past the derailleur anchor bolt, try this: release
the cable at the derailleur anchor bolt, push the cable
through the lever a little bit, tie a knot at the lever and
tighten the anchor.Voila.You can shift again.
PROBLEM:
It's very difficult to shift your twist shifters.
Clean and lubricate the cables. Still hard to
shift? Clean and lubricate the shifter.
SOLUTION:
PROBLEM: The shift housings are rubbing against the
frame and wearing out the paint.
Put tape beneath the housings where they rub.
Or, if possible, run the housings to the opposite stops and
cross the cables beneath the frame tube.
SOLUTION:
PROBLEM: The
derailleur doesn't shift like it used to.
Usually you can fix this by turning the adjuster
barrel on the lever or on the frame anticlockwise, adding
tension to the cable, making the derailleur move a bit further.
SOLUTION:
PROBLEM: You
can't find the head of the cable in your
Shimano STI or Campagnolo Ergopower levers.
SOLUTION: Shift
the lever to its starting position by clicking
the return lever ten times. The head will now be exposed.
Braze-On Shifter Installation
A gear shift lever is an assembly of several separable parts. It is very
important to pay close attention to the arrangement of parts while you
disassemble a shifter so you will be able to put them back together
correctly later. Fortunately, when you buy a new set of shifters, they will
already be assembled. If you buy braze-on-type road bike levers, they may
come attached either to braze-on bosses or to plastic facsimiles. You will have
to unbolt the lever assembly from the substitute boss in order to attach it to the
boss brazed to the bicycle frame, but you can hold the internal parts of the
lever together during this process to simplify the installation. Fit the lever unit
on its braze-on boss, making certain that all parts go on in the correct order.
Thread the tensioning bolt into the boss to hold the unit in place (see photo).
? The head of the tensioning bolt will either be slotted to accept a screwdriver, recessed to receive a hex key or fitted with a D-ring for hand
,- 0.11 tightening. The proper tightness of this bolt can be set only after the
gear cables are in place. If you're reusing the old cable housing, flush it out by
spraying a light solvent like WD-40 through with a thin nozzle. Similarly, clean
an old cable by spraying it down with WD-40, then wipe it down with a rag
– or better yet, with a piece of steel wool or other abrasive cleaning pad.
Nylon-lined cable housings and die-extruded cables available today work best
when kept perfectly clean. To install the cable, push the lever as far forwards
as it will go and thread the cable down through it from above. Pull the cable
all the way through until the fitting on its end is seated in the lever (see photo).
Then run the cable down towards the bottom bracket.
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ILLUSTRATED BICYCLE MAINTENANCE
3
Some bicycles are equipped with cable guides that are either brazed
or clamped on the down tube just above the bottom bracket area.
These guides direct bare cables over the top of the bottom bracket on
their way to the two derailleurs. On other bicycles, the cable guides are located
on the underside of the bottom bracket (see photo).
-
4
-MI
Install the cables. If you're using a section of housing, set it in place
and run the cable through it (see photo). Pull the end of each cable
through the anchor bolt at the derailleur that it will operate.
SHIFT LEVERS 163
5
Hold the end of the cable with a pair of pliers to keep it taut while you
tighten the anchor bolt with a hex key (see photo). When new cables
have been installed, move each shift lever back and forth a few times
to prestretch the cables, then recheck the adjustment. If a lever must travel
some distance before activating the derailleur to which it is attached, loosen
the anchor bolt and make the cable more taut, then retighten the bolt. Leave
about 4 cm (1% inches) of cable beyond the anchor bolt, and trim away the
rest with cable cutters.
6
VAIMINIUMIIIP
With the cables in place, the final step is to check the tension on
the lever. Check the front and rear derailleur in turn, running through
all the gears. This can be done on a repair stand, but can more adequately be done while riding. If the lever is hard to pull down, there is too
much tension on it. If it is easy to pull down but wants to upshift on its own,
it needs more tension. Adjust the tension by loosening or tightening the tensioning bolt as needed. If the bolt is fitted with a D-ring, you can make the
needed adjustment while riding the bike.
164 ILLUSTRATED BICYCLE MAINTENANCE
Bar-End Shifter Installation
1
When installing bar-end shifters, the brake levers must be installed first
because the brake lever's clamp won't fit over the shifter body. Begin
by fitting the shifter body into the end of the handlebar. Position them
so that the cable housing stop is at the bottom of the handlebar and the flange
the body is to the outside. Use a 6 mm hex key to turn the expander anticlockwise (the expander is located inside the shifter body).
Install the post and positioning washer onto the shifter body. The key
of the positioning washer should point down (see photo).
2
3
Mount the shift lever onto the post, matching the keyway on the lever
to the key on the positioning washer. The levers attach to the posts
with screws. For Shimano, the screw used on the left (front) shifter has
a broad head and the one used on the right (rear) shifter has a smaller head to
fit into a recess in the shifter. Select the correct one and tighten it in place using
a flat-blade screwdriver.
Trim the housing covers to match the length of the flat portion of the bottom
of the handlebar, and tape them in place.
SHIFT LEVERS 165
4
Fit a ferrule onto the end of a section of shift cable housing, and slide
it into the housing cover until it seats into the stop in the lever body.
Determine the proper length of the housing. Ideally, it will make a
gentle arc from the point it exits the housing cover on the handlebar to the
:able guide on the downtube of the frame.
5
Shift the lever up slightly. This will make a straight shot for you to insert
the cable into the shifter and feed it through the shifter body and the
housing. Run the cable to the derailleur and anchor the end. Give the
:able a few light tugs to seat the housing ends into the ferrules, and then take
,p any slack. Trim the cable about an inch from the cable anchor bolt and
:ri mp it with a cable end crimp (or use some other manner of making sure
he cable can't fray). Repeat these steps for the other lever.
6
_
Wrap the handlebar from bottom to top, allowing the housing to
emerge from the tape where the flat portion of the drop ends. Check
your shifting adjustment on the stand or by taking the bike out for a
slow ride in an open flat area, where you can safely concentrate on watching
the chain move across the sprockets.
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ILLUSTRATED BICYCLE MAINTENANCE
Brake-Lever Shift Lever Installation
1
Almost everyone loves these dual-purpose levers because they provide
several advantages: they can be reached from most hand positions,
allowing more frequent shifts, which saves energy; it's possible to shift
while out of the saddle; and you can brake and shift simultaneously.
Because brake-lever shift levers also operate the brakes, the brake cables
should be hooked up before installing the levers on the handlebar. To do this,
follow the steps on page 236. For Campagnolo Ergopower levers, however,
don't wrap the bar tape after you get the brake levers and cables connected
and installed on the bar.
IiIMINIIIIMPIE-
■111100
2
With the brakes set up and the levers attached to the handlebar, you
can hook up the shift cables and housings. Start by shifting the right
return button at least ten times and the left one three times. For
Campagnolo levers, push down on the buttons located on the inside faces
of the brake lever bodies.
3
For Shimano, push the smaller levers (located behind the main levers)
to the inside (see photo). Pick up the rear wheel and turn the pedals by
hand to allow the derailleurs to shift the chain into the small freewheel
cog/small chainring combination. Shimano STI models use housing sections
that run from stops built into the side of the brake lever bodies to the downtube stops. The housing sections are not wrapped under the handlebar tape.
Campagnolo Ergopower levers use similarly run housing sections, but they are
wrapped under the bar tape.
SHIFT LEVERS 167
4
Thread each cable through the hole (see photo) in the lever's shift
mechanism (you may have to open the lever to spot it). Pull the cable
to seat the barrel end in its holder.
5
Run the cables through the housing sections and back to the front and
rear derailleur anchor bolts. Be sure the housing sections are seated
in the lever and frame stops. Pull the ends of the cables with pliers to
remove slack and tighten the derailleur anchor bolts. Trim the cables from 2 to 4
cm (1 to 11/2 inches) past the anchors, then install aluminium end caps and crimp
them in place with pliers or diagonal cutters fo prevent fraying (see photo!. If
(ou
have installed new derailleur cables, shift the derailleurs several times to
stretch them and seat the housing sections. Pluck the cables by the down tube.
f you've created slack, loosen the anchor bolts, pull the cables taut and
.etighten the anchors.
On Campagnolo levers, you'll need to wrap the handlebar. Hold
the brake and shift housings in place on the bar with a few pieces of
electrical tape. The bar is most comfortable to grip if you run the brake
housings along the front of the bar and the shift housings along the back (see
photo). When the housings are in place, rewrap the bar tape.
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ILLUSTRATED BICYCLE MAINTENANCE
Twist-Grip Mountain Bike Shifter
Removal, Installation and Service
/1 SRAM's Grip Shift shifters have gone through many evolutions over the
years, making it difficult to cover all possibilities in this text. We'll cover
...
their most recent incarnation – if you have an older model, service
instructions are readily available at SRAM's Web site.
lb remove your twisters, shift onto your smallest chainring or cog. Remove the
:able-end crimp and release the cable anchor bolt on the derailleur. Open the
:able hatch. On front shifters, the cable head will be secured by a hex screw;
,n rears, by a plastic clip. Remove the screw or push the clip aside and slide
he cable out. If you're only replacing the cable, you're halfway done: just
'everse these steps to finish. If your shifter needs a bit more care read on.
2
Slide the stationary grip off the handlebar and loosen the clamp bolt
that locks the shifter body to the bar. The shifter will slide right off the
bar. Separate the twist-grip from the shifter body by pinching the
•etaining clips inside the sleeve and sliding the twist-grip off.
3
When you have your shifter apart, you'll see how simple its inner
workings really are. To clean the parts, use a plastic-friendly degreaser
li ke Pedro's Bio Cleaner. Never use citrus- or petroleum-based
degreasers; they'll melt the plastic and ruin the shifters permanently.
SHIFT LEVERS 169
4
Apply a bead of Grip Shift-approved grease like Jonnisnot or Finish
Line Grip Shift Grease to all contact points within the shifter. The most
critical points are where the twist-grip rides on the sleeve, the detente
notches and the grooves where the cable rides.
Slide the twist-grip about halfway onto the sleeve. Set the spring in
place on the two pins, and twist the grip and body to slightly compress
the spring as you mate the two parts. Before reinstalling the retaining
clip, shift back and forth through the gears to be sure everything is seated correctly. With this established, snap the retaining clip into the end of the sleeve.
6
-
411111.
'low
Reattach the shifter to the handlebar. The best location for the shifter's
cable adjuster is just below and behind the brake lever so it's protected
in a crash but easily reached with your thumb and forefinger if you
should need to make a quick cable adjustment while riding. Slide the stationary
grip back on. It's easiest to do this after spraying a little alcohol into the grip.
The alcohol lubricates the grip well enough to ease installation but evaporates
quickly, leaving the grip tight on the bar. Replace the cable (along with the
screw on the front shifter) and readjust the shifting.
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ILLUSTRATED BICYCLE MAINTENANCE
Mountain Bike Thumb Shifter
Removal and Installation
1
Thumb shifters found on mountain bikes are mounted on handlebars in
a location where they can quickly be reached by the rider's thumb. Like
down-tube shifters, mountain bike thumb shifters come in pairs, one
for each derailleur. They are available as index (most common today), friction
or ratcheting types. Also, like their down-tube cousins, older thumb shifters use
friction washers and tensioning bolts to regulate the level of friction.
Most thumb shifters can be moved after loosening the lever's clamp bolt.
These are usually in plain view on top of or under the handlebar (see photo).
2
To remove the lever from the handlebar, slide off the grip and brake
lever. Remove the grip by cutting it off if you're going to put on new
grips. If not, lift up the edge with a screwdriver and squirt some
alcohol under it to make it slippery enough to pull off the bar (see photo). Once
the grip is off, loosen the brake lever clamp bolt enough to slide off the brake
lever, then loosen the shift lever clamp and remove the shifter. Usually it's not
necessary to detach the cables.
3
Some mountain bikes have shift levers that are built into or attached to
the brake levers. On these, when the hex bolt securing the brake lever
to the handlebar is loosened, the shift lever will come off with the
brake lever (see photo). Older SunTour levers have yet another design. If your
SunTour shifter has a D-ring on top, unscrew the D-ring completely to loosen or
remove it. When it's free, lift the lever, bolt and washers off the shifter base.
Underneath you'll find a nut, which, when turned anticlockwise, loosens the
clamping band and allows you to move the lever base.
SHIFT LEVERS 171
Three-Speed-Type Shifter
Removal and Installation
1
The thumb shifter on a three-speed bicycle is generally fastened by
a removable clamp to the right side of the handlebar. The shifter is
connected by cable to a set of gears located inside the rear hub of the
bicycle. When a thumb shifter of this type goes bad, it must be replaced. It
cannot be dismantled for repair or replacement of parts.
Begin the removal of a three-speed shifter by loosening the cable at the hub.
This is done by unscrewing the fitting on the end of the cable from the fitting
connected to the short length of chain that emerges from the rear hub.
2
RM.
Use a screwdriver to loosen and remove the nut and bolt in the clamp
that holds the shifter on the handlebar (see photo). Take out the bolt,
gently spread the clamp apart just enough so it fits over the handlebar,
and remove it and the shifter from the handlebar.
3
Free the fitting found on the upper end of the cable from the lever, and
slip the cable out of the shifter. There may be a catch plate in the way
that must be lifted before you can disconnect the cable. Or, the entire
body of the shifter may be enclosed in a plastic cover that must be slipped off
before the cable can be freed (see photo).
Fit the end of the cable inside the new shifter and fasten it to the handlebar,
reversing the steps of the removal procedure. Lubricate the shifter with a few
drops of oil.
CHAPTER 10
Front Derailleurs
The front derailleur's simple appearance belies the complexity involved in its proper alignment and adjustment. The
task of moving the chain from one chainring to another is
handled by applying pressure to the side of the chain. While
pedalling, the left shifter tenses or relaxes the cable, which in
turn moves the front derailleur cage or allows a spring to
return it to its normal position. Either of these actions forces
the chain to climb off the teeth of one ring and onto the
next. To do this is one thing; to perform the job consistently
well is quite another.
Adding difficulty, the front derailleur must accomplish its task of moving the chain from one chainring
to another while the chain is under tension, because
it operates on the top or loaded part of the chain
rather than on the slack lower run as the rear derailleur
does.
In many cases, the derailleur moves back and forth
between two chainrings, or what is known as a double
chainring. The popularity of mountain bikes and their more
casual offshoots, however, has made triple chainring sets
commonplace. Triple chainrings require a front derailleur
that can move over a wider range than is necessary for a
double chainring. For this reason, derailleurs that are perfectly acceptable for doubles may not work well on triples.
ROAD DOUBLE
TRADITIONAL
'TRAPEZE' STYLE
(OR BOTTOM SWING;
How Front Derailleurs Work
Front derailleurs are designed only to push the chain from
side to side, rather than to both push and lift it. The speed at
which they do this, or the speed of the shift, is determined
by several design factors: the height of the cage plates (the
two horizontal plates that push the chain back and forth), the
width or distance between the cage plates, and the rigidity of
the entire derailleur body. The distance between the
derailleur and the chainring teeth and the type of chain used
also affect the speed of the shift.
The width of the cage plate is important because this
determines how much of the chain is pushed. The wider the
cage plate, the more area there is to push against the chain.
However, there are limits to how wide the inner cage plate
can be. The outer cage plate must be positioned to clear the
outer chainring by only 1 to 3 mm, so if the inner cage plate
is too wide, its bottom edge may strike the top of the middle
chainring as you try to shift to the outer ring.
It was noted earlier that a wide cage plate has more area
to push against the chain.You can also turn this around and
ROAD TRIPLE
TOP SWING
Front derailleurs designed for wide-range gearing have tall inner cage
plates. They can hang up on the middle chainring teeth if that chainring
is too close in size to the large chainring.
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ILLUSTRATED BICYCLE MAINTENANCE
The Chainring Changer
■ CABLE ANCHOR
CLAMP BAND
CLAMP BOLT
■ INNER ARM
OUTER CAGE PLATE
INNER CAGE PLATE
FRONT DERAILLEURS 1 75
say that the wider the plate, the greater the area the chain has
to push against. This means that as the derailleur cage gets
wider, its body must get stiffer to resist twisting because of
the chain's extra leverage. The body of the derailleur and the
arms that attach it to the cage must resist flexing or twisting
during the shift. The stiffer the body of the derailleur, the
faster the unit will shift.
The distance between the cage plates also plays a role
in the speed of the shift. The closer the cage plates straddle
the chain, the more control you will have over the chain and
the speed of the shifts. The one drawback to this is that the
narrower the cage, the more you will have to adjust it as you
shift the rear derailleur — as you shift in the rear, the angle of
the chain changes, which can cause it to rub on the tail of
the front derailleur.
The Wave
Because indexed shifters don't have as much capacity for
trim as their older friction cousins, front derailleur cage
shapes have been continually refined. They now incorporate
ramps and twists that, along with small hooks and rivets on
the sides of the chainrings, give the chain a little extra lift to
make shifts from a smaller chainring to a larger one.
Precision like this comes with a price. Most front
derailleurs today are designed to work as one part of a larger
system that includes the rear derailleur, the shift levers and a
specific arrangement of chainrings. Generally, for best performance, you should stick to a set of levers, derailleurs and
chainring sizes that were made to be used together.
Selecting a Front Derailleur
When selecting a front derailleur, first consider the capacity
you need. Most derailleurs specify the range in teeth (10
teeth, 14 teeth) that they can handle. This number refers to
the difference in size between the small and large chainring.
To find the range of your chainrings, subtract the number of
teeth on the small ring from the number of teeth on the
large ring.
Racing derailleurs usually have ranges from 10 to 16 teeth.
Sport derailleurs can often handle differences of 20 teeth,
whereas wide-range touring units can go as high as 26 teeth.
The numbers provided by derailleur manufacturers are
usually conservative, and if you make a small compromise,
you can often exceed them. The specified range is based on
the calculation that if the chain length is correct and the correct rear derailleur is used, the chain will not drag on the
front derailleur cage when you shift to the small-cog/smallchainring combination. When a chain drags, it does so across
the lowest point of the derailleur, which is the spacer that
connects the tail ends of the two cage plates.
Actually, you should not ride in the small/small combination even if your chain does not drag, since the extreme
angle that this gear creates accelerates chain wear. By not
shifting into this combination, you can use a slightly smaller
inner chainring than would otherwise be possible without
experiencing chain drag. In order to avoid chain drag with
triple-chainring sets, it's often advisable to use the tiny inner
chainring only with the three to five innermost cogs on the
freewheel.
Front derailleurs designed for road racing usually have
narrower cage plates than the mountain units. Road racing
derailleurs will shift faster because of their narrow cages, but
they need more correction as you shift in the rear.That is to
say, to avoid rubbing the chain on the cage plates, the front
derailleur will have to be moved slightly in or out as the
chain moves in and out on the rear.
Be sure to find a derailleur that matches the requirements
of your frame, as well. Look carefully at how it's mounted, or
take your bike or old derailleur to the shop for advice. This
is important because there are front derailleurs that mount in
unusual ways, such as to a plate between the bottom bracket
and shell.
When selecting a new front derailleur, look also at the
routing required for its shift cable. Most derailleurs require an
open cable that is routed through cable guides. Some older
ones are designed to work with cable enclosed in one or
more sections of cable housing that fit between housing
stops, including a stop built into the derailleur. If your bike is
equipped for a closed cable but you have chosen a front
derailleur that requires an open one, you may have to put a
cable guide beneath the bottom bracket to make everything
work.You may also have to replace the shift cable because the
new routing may be longer than the old one. If you are concerned about this, check with the dealer before buying the
derailleur.
On mountain bikes, there are front derailleurs known as
top pull or bottom pull, based on which direction the cable
comes from. It's important to select the appropriate style of
replacement derailleur for it to work correctly.
Some road frames — usually chrome-moly models from
small custom builders or carbon fibre frames with unusually
large or oddly shaped tubes — have braze-on front derailleurs.
This means that there is no band around the seat tube to
hold the derailleur. Instead, a special fitting is permanently
attached to the seat tube and the derailleur is bolted to that.
If you have a braze-on fitting, be sure that the derailleur you
want is available in a braze-on model.
Maintaining the Front Derailleur
A front derailleur has few working parts, but it is important
to keep the unit clean. The grit that builds up on the
derailleur body eventually works its way into the bearing
surfaces. Once inside, the grit acts like sandpaper and cuts
into the bearing surfaces, causing premature wear. This wear
1 76
ILLUSTRATED BICYCLE MAINTENANCE
translates into play or slop in the mechanism, which causes
the derailleur to shift poorly. Remember, stiffness is important for crisp shifting performance.
Clean the grit off the outside and out of the inner workings of the derailleur with the help of a solvent. Wipe the
derailleur clean and allow all the solvent to evaporate, then
lubricate the pivot points with a light lubricant. Spray a little
of the lubricant in the openings at the ends of the lifting
arms, shift the derailleur and spray a little more. Wipe away
any excess or it will quickly attract new dirt.
derailleur.
Adjustments for Special Problems
SOLUTION: The
If your derailleur is sluggish or shifts too far and the situation
cannot be corrected with the adjusting screws, it often helps
to custom-tailor the shape of the cage.
If the chain tends to overshoot the outer chainring, or if
the derailleur shifts sluggishly from the large chainring to the
small chainring, bend the nose of the outer cage slightly in
towards the chain. However, do not bend it so far that the
cage rubs the chain.
On the other hand, if the chain won't shift to the large
chainring, look at the inner cage from above.The nose of the
cage plate should bend slightly in towards the chain. If it does
not, then bend it, but not so far that the cage rubs the chain.
Check the cage plates from the front if you are still having
problems. If the inner cage plate is not parallel to or slightly
toed-in towards the outer chainring, bend it in until it is.
Make sure that your shifting problem is not caused by a
poorly adjusted gear cable. If your shift lever moves some distance before tensioning the cable, there is too much slack in
the cable. Push the lever all the way forwards and take up the
slack at the cable anchor bolt. On some setups, you can take
the slack out without tools by turning the adjustment barrel
on the lever or frame stop anticlockwise.
If you find you have to adjust your front derailleur after
every one or two shifts of the rear derailleur, you can modify
it to make the cage a bit wider. Loosen and remove the bolt
holding the spacer in the tail of the derailleur, and slip a small
washer between the spacer and the inner cage plate.
Spreading the cage plates further apart in this way allows the
chain to move through a wider angle without rubbing.
TROUBLESHOOTING
PROBLEM: When you climb out of the saddle, the chain
rubs the derailleur.
SOLUTION: Adj ust the low-gear adjusting screw so there's
more clearance between the cage and the chain when in
low gear.
PROBLEM: When
you stand to sprint, the chain rubs the
chainring may be slightly bent. Sight it to
see, and have it trued if it's bent. Or, adjust the high-gear
adjusting screw to provide more clearance between the
cage and the chain when in high gear.
PROBLEM: The
derailleur won't shift to the smaller
chainring.
SOLUTION: Make
sure that the cable is moving smoothly.
Check that the angle of the cage is parallel to the chainrings, that the low-gear adjusting screw allows the derailleur
to move far enough to the inside and that the nose of the
derailleur is slightly bent towards the chain.
PROBLEM: The
derailleur won't shift to the large
chainring.
Check that the angle of the cage is parallel to
the chainrings, that the high-gear adjusting screw allows the
derailleur to move far enough to the outside and that the
cage's nose is slightly bent towards the chain.
SOLUTION:
PROBLEM: The derailleur won't shift to the middle ring
on a triple chainring.
SOLUTION: Make sure that the chainring is correctly
installed. If it's upside down or the spacers are incorrect,
the chain won't be able to find the chainring.
PROBLEM: The anchor bolt got stripped when you
tightened it.
SOLUTION: Try
tapping it to a larger bolt diameter and
installing a larger bolt.
PROBLEM:
During a ride, the chain falls off while you
are shifting to the small chainring.
Usually, it's possible to just keep riding. Pedal
very gently and shift the derailleur. With luck, the chain
will shift back onto the chainring. If the problem is
chronic, check the adjustment of the inner limit screw.
SOLUTION:
PROBLEM: The
SOLUTION: If
chain rubbed a hole in the cage.
possible, install a new cage. Or, replace the
derailleur. When riding, be sure to not allow the chain to
rub and wear out the new derailleur.
FRONT DERAILLEURS 177
Front Derailleur
Basic Maintenance
A front derailleur that moves sluggishly and is difficult to shift probably
has grit and grime in its few moving parts. Most likely, a thorough
cleaning and lubrication will dramatically improve its performance.
Lubrication of a front derailleur is most easily done with the derailleur on the
bike. Leaving the derailleur in place allows you to shift it back and forth while
the lubricant is being applied to its pivot areas. However, cleaning is another
story. The best way to thoroughly clean a front derailleur is to remove it from
the bike and soak it in solvent. Fortunately, removing a front derailleur is a
simple process, one that takes only a small amount of time. First, shift the
lever forwards to take tension off the gear cable, then loosen the cable
anchor bolt and disconnect the cable from the derailleur.
The main thing that now prevents you from removing the derailleur
from the bike is the chain that is trapped inside its cage. The chain
can be broken with a chain tool, but a simpler solution to the problem
is to remove the pin that serves as a spacer between the tail ends of the two
derailleur cage plates. Unscrew the bolt that holds the pin in place, remove the
pin and the chain will slip out of the cage.
If you have a front derailleur with a nonopening cage (found on some late1990s bikes), we recommend removing it only for replacement. For cleaning,
brush it while it's on the bike. To remove the derailleur, you must break the
chain. If you're replacing the derailleur because it's worn out, cut the cage
with a hacksaw to extract it from the chain. Another option is to simply slide
the derailleur down the chain to where you can clean the derailleur almost as
easily as if it were free from the chain.
1 78
ILLUSTRATED BICYCLE MAINTENANCE
3
When both the cable and chain are out of the way, the derailleur can
be removed from the bike. Locate the bolt that fastens the derailleur's
clamp to the seat tube or the derailleur to a braze-on mount. Loosen
and remove that bolt. Be sure to put it back in place in the derailleur (after the
derailleur is removed) so that you won't lose the bolt.
4
If the derailleur is attached to the seat tube by means of a clamp,
spread the jaws of the clamp and remove it from the tube (see photo).
Soak the derailleur in a small container of solvent to loosen the grit in
its bearing areas. While it soaks, give the lower part of your seat tube a
cleaning and polishing, especially the area normally covered by the clamp.
Use an old toothbrush or other stiff brush to loosen any grit or grease that is
clinging to the derailleur. Rinse the derailleur in the solvent once more, then
wipe it clean with a rag. Let the clean derailleur sit for a little while to allow
ti me for the solvent to evaporate from its working parts.
Try to fasten the front derailleur back on the bicycle exactly where it was before.
Then use the instructions on page 180 to adjust it. When the derailleur is properly
located, reattach the gear cable to it. Squirt a little light oil or an appropriate spray
lubricant into each of the derailleur's pivot points. Shift the derailleur a little bit and
apply more lubricant. Shift it back and forth a few times to spread the lubricant
around its working parts, then use a clean rag to wipe away any excess. Oil that
is left on outer surfaces will only attract fresh contaminants.
FRONT DERAILLEURS
179
Front Derailleur Installation
1
When installing a front derailleur, it is not necessary to break the chain
if it is already on the bike. (A few late-model front derailleurs have
cages that can't be opened. These require you to break the chain to
install the derailleur.) Simply remove the spacer from the tail of the derailleur
cage, drop the cage down around the chain and replace the spacer. However, if
the chain is already broken, there is no need to remove the spacer pin. Just
install the derailleur, run one end of the chain through it and rejoin the ends of
the chain. If the derailleur is equipped with a clamp, take out the clamp bolt and
spread the jaws of the clamp band. Fit the clamp band around the seat tube of
the bike at approximately the correct height, and replace the bolt.
Tighten the clamp bolt to prevent slipping, but not so tight that it cannot be
moved by hand (see photo).
2
If the derailleur is a braze-on model, fasten it securely to the braze-on
mount, then partially loosen the height-adjusting bolt. Before you
reattach the gear cable, set the derailleur to the right height and
angle. Keep the chain out of the way during these adjustments by slipping it
off the chainring to the inside and letting it rest on the bottom bracket shell.
Pull the derailleur cage out over the large chainring, watching the outer plate
of the cage as it passes over the chainring teeth. Adjust the derailleur height
so that the cage clears the tallest chainring teeth by 1 to 3 mm.
1 80
ILLUSTRATED BICYCLE MAINTENANCE
3
Let go of the derailleur cage and sight down from above. Make sure
that the cage's outer plate is aligned parallel with the chainring (see
photo). Once both the height and horizontal alignment are set, tighten
the clamp bolt to hold the derailleur in that position.
4
Push the chain inside the derailleur cage and wrap it around the
small chainring. Fit the spacer back into the tail and bolt it into place
or rejoin the chain (see photo). Flush each section of derailleur housing
with WD-40, then thread a new gear cable through the shift lever and cable
housing and route it to the front derailleur.
Be aware that some bikes are set up so that the cable runs above the bottom
bracket on the way to the front derailleur, others run the cable below the
bottom bracket and still others route the cable from the top down. Also, note
that some front derailleurs are designed to receive open cable; others have a
cable housing stop and are designed to be used with a section of housed
cable. If your new derailleur is not compatible with your bike, return to the
shop and get the correct one.
FRONT DERAILLEURS 181
5
Run the cable through the anchor bolt on the derailleur and pull it
taut. Hold the end of the cable with a pair of pliers while you tighten
the anchor bolt (see photo). Push the shift lever a few times to pre-
stretch the cable, then loosen the bolt, take up any slack and retighten.
A new gear cable will almost certainly be longer than necessary. So
after installing a new cable, leave approximately 2 to 4 cm (1 to 11/2
inches) of wire extending beyond the anchor bolt, and use a sharp
pair of cable cutters to trim away the rest (see photo). Crimp a cap on the cable
end to prevent fraying.
After installing a front derailleur, follow the steps on pages 182 and 183 to
make sure that it is properly adjusted before riding the bicycle.
1 82
ILLUSTRATED BICYCLE MAINTENANCE
Front Derailleur Adjustment
1
After installing a new derailleur, set its range of motion. This
adjustment may need to be made periodically to an old derailleur
as well. If you have trouble shifting onto any chainring or if a full
shift in either direction tends to throw the chain past the intended chainring,
it is definitely time for an adjustment.
Begin by shifting the chain to the inside onto the small chainring and largest
freewheel cog. Locate the adjusting screw for setting the inner stop on the
derailleur. Derailleurs with limit screws arranged horizontally come in two
basic types: traditional and top swing. If the derailleur is a braze-on type or if
the frame clamp is above the cage, this is a traditional derailleur and the
inner limit screw is the one closest to the frame. If the frame clamp is below
the top of the cage, this is a top-swing derailleur and the screws are reversed.
Fortunately, top-swing derailleurs usually have the screws labelled 'high' and
'low' to reduce confusion (see photo). If they are positioned vertically, it will
probably be the one on top. Set the stop so that the inner plate of the
derailleur cage is held 2 mm from the inside of the chain.
2
Shift the chain to the outside, onto the large chainring and the smallest
rear cog. Set the other adjusting screw so that the outer plate of the
cage is held about 2 mm outside the chain (see photo). These settings
should allow you to shift between chainrings and not be left with the chain
rubbing the derailleur cage after the shift. Be sure to test the bike to check the
adjustments. If the chain tends at all to rub on the inside with the first setting
or the outside with the second, these limits will have to be slightly expanded.
But don't set them so wide that the chain will come off the chainring during a
rapid shift, and in no instance should the derailleur move so far out that it
strikes the crankarm.
FRONT DERAILLEURS 183
3
If you're getting sloppy shifting performance with your front derailleur,
look closely at its shape. Most manufacturers bend the front ends of
the cage plates slightly in towards one another to create a narrow
nose for more authoritative shifting. If your derailleur needs its nose narrowed,
use a pair of pliers to gently toe-in the plates.
4
Often, when a shift is made with the rear derailleur, the change of
chain angle causes the chain to rub the tail end of one of the front
derailleur cage plates (see photo). This is especially common on a bike
with a narrow derailleur cage and eight, nine or ten cogs. The rubbing will
eventually wear out the derailleur. Usually, all it takes to cure this is a slight
adjustment of the shift lever, which is called trimming the derailleur.
5
To eliminate or reduce chain rub after rear shifts, you can try to widen
the back of your derailleur cage a bit. (This is not possible if you have
a derailleur with a cage that cannot be opened.) Partially remove the
bolt holding the spacer pin in the tail of the cage. Slip a small washer between
the spacer and the inner cage plate of the cage, then retighten the bolt.
One final problem that you may encounter with a front derailleur is chain
drag on the tail pin in certain gear combinations. For example, shifting the
chain onto both a small chainring and small rear cog drops it low in the cage,
which may cause it to drag. The solution is simple: don't use the chain in this
gear combination. Even if no chain drag occurs, such a gear combination puts
the chain at an extreme angle and should be avoided.
Chain drag may also result from a mismatch between the front derailleur and
the chainrings. The solution here is obvious: if you intend to use extra-small
chainrings, equip your bike with a derailleur that is designed for them.
CHAPTER 11
Rear Derailleurs
In the early days of friction downtube shifters — short,
The broad range of gear selection made available through the
advent and refinement of the rear derailleur has made cycling direct cable routes — and five-speed freewheels; keeping a rear
accessible and enjoyable to many millions throughout its his- derailleur functioning properly was a relatively simple task.
tory. In addition, the wide range of ratios availed by the rear Close was close enough in many cases. The latest technology
derailleur is what made mountain biking — as we know it involving closely spaced cogsets in the double-digit realm and
today — possible. Try as some might, there has yet to be a integrated brake/shift levers with precise, clockworklike
system of gear changing as light, effective and efficient as that internal mechanisms has added all-new levels of complexity
to the proper care and maintenance of rear derailleurs.
found on the now typical chain-driven, derailleured bicycle.
Unless you ride your bicycle only on flat land or along the
Types of Rear Derailleur
beach on breezeless summer days, you know when your
There are two fundamental types of rear
rear derailleur isn't working. It can be sluggish
derailleur: short cage and long cage.
moving from one gear to another. It can
Cage refers to the two side plates that
misalign with a cog and cause your
hold the derailleur pulleys apart. A
chain to jump back and forth
short-cage derailleur is used
between two gears — usually at
primarily in conjunction
the most inopportune time, of
with two-chainring drivecourse. Or, worst of all, it can
trains like those common
push itself and the chain
on road racing bikes.
into the spokes of your
derailleurs
Long-cage
rear wheel, ending your
allow for a greater differride in a hasty fashion.
ence in cogset and
Hanging out in space
SHIMANO DEORE LX
chainring
combinations
on the right side of your
(A REAR DERAILLEUR FOR
MOUNTAIN
BIKES)
and
so
are
most
common
the
is
rear
bike
on any bike with a triple
derailleur's primary vulchainring or a very widenerability. Contact with a
CAMPAGNOLO RECORD
range
cogset at the rear.
rock on the trail, another
(A REAR DERAILLEUR FOR
There
are
also mid-cage or
rider on the road or an
ROAD BIKES)
medium-cage rear derailleurs
unfortunate tumble on the
Rear derailleurs made for double-chainring road bikes
that are sometimes favoured by
pavement outside your favourite
have short chain cages, whi le those made for widecross-country mountain bike
coffee shop can render your rear
range, triple-chainring bikes , such as mountain bikes,
racers who use close-ratio triple
derailleur useless. But there are other
have longer cages for great er amounts of chain wrap.
drivetrains, but these are relatively
enemies that lurk and they aren't
uncommon and almost never seen as
always so obvious.
Dirt, grit, corrosion and wear all play major roles in hin- original equipment on any bicycle these days.
dering the performance of even the most robust derailleurs. A
bit of careful cleaning and maintenance, though, can extend Making the Upgrade
Replacing a rear derailleur requires that you keep several comthe life of a well-made rear derailleur almost indefinitely.
Derailleurs work — as the name implies — by 'derailing' the patibility issues in mind.
First and foremost, will the shiny, new derailleur in the
chain from one sprocket to another. A cable, drawn by your
shift lever, opposes a spring inside the derailleur. When you glass case that has caught your eye work with the shifters and
move the shifter to pull the cable, it overcomes the spring and cogset that you have on your bike? Where indexed shifting is
moves the chain in one direction. When you move the lever concerned, you can usually get away with using an eightto release the cable, the spring recoils and pulls the chain in speed derailleur on seven cogs, a nine-speed on eight cogs or
a ten-speed on nine cogs, but not the other way around.You
the other direction.
1 86
ILLUSTRATED BICYCLE MAINTENANCE
Quick-Change Artist
INNER CAGE PLATE
IDLER (TENSION)
PULLEY
B-KNUCKLE
JOCKEY (GUIDE)
PULLEY
CABLE ANCHOR
P-KNUCKLE
PIVOT BOLT
LI MIT SCREWS
REAR DERAILLEURS 187
also need to know that Campagnolo doesn't work with Shimano; old SunTour doesn't work with anything else, but new
SunTour works with Shimano; and some SRAM models
work with Shimano and some don't. Start throwing around
names like Sachs or Proshift, and it gets even harder to follow.
It's a complex problem that could make you think you'd
rather take up programming VCRs in your spare time.
Luckily for you, there are knowledgeable people at your local
bike shop who actually enjoy discussing and debating these
subtle issues of compatibility. Let them help you determine
what will work and what won't.
How Rear Derailleurs Work: The Rest of the Story
We discussed in fairly simple terms how derailleurs move the
chain from one cog to another. The rear derailleur's second
function, though no less important, is to maintain tension on
the chain throughout your bike's entire range of gearing.
The cage of every rear derailleur is spring-loaded. The
spring tension works to rotate the cage towards the back of the
bike. When the chain is riding on the small-chainring/smallcog combination, the derailleur cage rotates back, taking up
slack in the chain. Shift to a larger ring or a larger cog, and the
cage is drawn forwards, maintaining tension on the chain but
allowing it to wrap around the larger gears.
Tremendous improvements in rear derailleur systems have
occurred over the past several decades, so many moderately
priced bikes sold today come with derailleurs that perform
better than some systems used by racers in the 1970s and
1980s. Overall, differences in performance in the current
models are not as dramatic as in the earlier period. Before,
the range in quality was excellent to awful; these days it is
excellent to acceptable.
Derailleur Anatomy
The body of the derailleur has a parallelogram form and is
equipped with a spring to move it in one direction and a
cable to pull it in the opposite direction. The spring is constantly pushing against the derailleur so that when tension is
completely off the cables, the derailleur moves the chain out
to the smallest cassette cog.The gear cable and shift lever must
be able to overcome the resistance of the spring.
Attached to the derailleur body is a structure called the
derailleur cage. The derailleur cage is the part that encloses
the chain and actually moves it from cog to cog. The cage
consists of two vertical plates (cage plates) and two small
rollers. The chain follows a backwards S-path around the
rollers, which position it.The upper roller is called the jockey
pulley; it guides the chain from one cog to the next. The
lower roller is called the idler pulley; it keeps the chain tension constant.When the chain moves from one cog to a larger
or smaller one, the derailleur cage pivots and moves the idler
pulley forwards or backwards to take up slack or feed out
extra chain as necessary.
There are two basic derailleur body designs: the single
pivot and the double pivot. SRAM ESP rear derailleurs are an
example of a single pivot. In this design, the derailleur body
sits at a fixed angle in relation to the cassette. The body of the
derailleur stays at this predetermined angle throughout all the
SHIMANO DEORE LX
REAR DERAILLEUR
SHIMANO DEORE XT
REAR DERAILLEUR
Most rear derailleurs are sprung so that the derailleur naturally returns to
the small-cog position (left). Low-normal derailleurs, on the other hand, are
sprung to return the derailleur to the large-cog position (right).
1 88
ILLUSTRATED BICYCLE MAINTENANCE
A less-expensive bike may feature a rear derailleur that is attached to the
frame via a bolt-on hanger. It's a good idea to regularly check the nut that
holds this hanger on the frame so it remains tight. Otherwise, the rear
derailleur may come off when you remove the rear wheel, complicating
reinstallation of the wheel.
shifts. Only the cage changes its angle as it pivots forward and
back to feed out chain or take up slack.
A double-pivot derailleur has a pivoting chain cage like the
other type. It also has a spring in the upper end of the
derailleur body that causes the derailleur body to move forward as the derailleur is shifted to the smallest cogs. This forward rotation allows more of the chain to wrap around the
cassette cog for a more positive engagement between chain
and cog teeth. This swinging action also allows the derailleur
to move back and lower down when shifting the chain onto
larger cogs.
The cage of the derailleur also affects the performance of
the derailleur. The length of the cage contributes to the
derailleur's ability to wrap up extra chain. The longer the
cage, the greater the capacity of the derailleur.
Longer cages aren't necessarily the best solution for all bikes,
though. A longer cage has difficulty maintaining as high a level
ofchain tension as a shorter one.This can result in slower shifting.
So, in cases where top performance is the primary concern, it's
best to use a derailleur with the shortest cage that is compatible
with your desired cog- and chainring sets.
Selecting a New Rear Derailleur
When selecting a rear derailleur, you must first consider the
capacity you need. Most derailleurs specify the range in teeth
– 20 teeth, 30 teeth, whatever – that they are designed to
handle. This number refers to the difference between the
small and large chainring plus the difference between the
largest and smallest cassette cog. To find the range of your
chainrings, subtract the number of teeth on the small ring
from the number of teeth on the large ring. For the cassette,
subtract the number of teeth on the smallest cog from the
number of teeth on the largest cog. Add the two numbers
together to find the number you need to know to select the
proper rear derailleur.
Racing double derailleurs usually have ranges from 20 to
26 teeth. Wide-range mountain bike triple units can go as
wide as 40 teeth.
The specified number is usually a conservative estimate on
the manufacturer's part. It is based on the possibility that you
might try to use all possible gear combinations. But it is never
advisable to ride with your chain simultaneously on the
smallest chainring and the smallest cassette cog. If you avoid
this gear combination, as you should, you can probably
exceed the stated range a little bit. On a triple-chainring set,
the tiny third chainring is often usable only with the three to
five innermost cogs on the cassette.
Derailleur Mounting
Rear derailleurs mount on the bike frame in one of two ways:
a bolt-on hanger or an integral hanger.The bolt-on hanger is
the least expensive and is found most often on bikes sold
through department stores and toy shops, or on only the most
inexpensive bikes sold through independent bicycle dealers.
The bolt-on hanger is held in place with a small alignment
bolt and the axle of the bicycle.
The integral dropout hanger is found on most bicycles
today. In this case, the derailleur hanger is actually an extension of the dropout. An integral hanger is usually stiffer than
a bolt-on hanger, which makes for better shifting. With bolton hangers, use the hanger supplied by the manufacturer.
Because aluminium can be bent and rebent only a few
times before it fatigues and cracks, integral hangers on aluminium dropouts are designed to be easily replaced. To the
untrained eye, replaceable hangers could be confused with
bolt-on ones.To tell them apart, bear in mind that bikes with
replaceable hangers will generally have vertical dropouts,
while bolt-on hangers work only with horizontal dropouts.
The shape of the derailleur hanger is especially important
when working with index derailleurs, all the modern types
that are shifted via levers that click with each shift.
The distance from the centre of the rear axle to the centre of
the derailleur mounting hole should be 3 cm or less. If
the derailleur is too far below the cogs, the indexing may
function poorly.
It's also critical that the hanger isn't bent. If you suspect
hanger or dropout damage, take your frame to a shop and
have it checked.
REAR DERAILLEURS 189
Once properly adjusted, a rear derailleur that is correctly
matched to a cassette should shift well and be quite dependable. Derailleurs made these days rarely stop working because
they have gone out of adjustment. The problems they develop
usually arise from crashes, dirt and misalignment. To work
properly, a rear derailleur must be kept clean, well lubricated,
correctly aligned and adjusted.
Maintenance
If your rear derailleur fails to perform as well as you think it
should, check the cable and housing first — corrosion, fraying
and dirt contamination are common problems. Try lubing
the cable or replacing it if it's bad. If the derailleur still has
problems, check it closely. Bend down behind the bike and
take a close look at the derailleur to see if perhaps it may
have been bent. The pulley cage ought to be parallel to the
centreline of the bike. If it's straight when sighted from
behind, an imaginary line drawn through the cassette cog
will bisect the pulley wheels. If the cage tilts in towards the
wheel, either the cage, the derailleur body or the hanger
(possibly even the dropout tab to which the hanger is
attached) may be bent. Check all three.
Precise hanger alignment is not necessary with frictionstyle rear derailleurs (those relying on shifters that don't click
into position with each shift), so you can try to align a bent
hanger with an adjustable spanner or a hex key. Unbolt the
derailleur and remove it from the hanger. Leaving the wheel
in place, use the jaws of the adjustable spanner to straighten
the hanger. If the derailleur uses a hex-key mounting bolt,
you can leave the derailleur mounted on the hanger. Simply
insert the hex key into the head of the bolt and use it while
also pulling out on the derailleur itself as a lever for bending
the hanger back into line.
These measures won't suffice for index systems because the
hanger must be exactly parallel to the cassette cogs. You can
try aligning it with an adjustable spanner, but it takes a good
eye to get it right. Also, while using a hex key to align hangers
may work fine on friction derailleurs, many index derailleurs
have 5 mm mounting bolts, and a 5 mm hex key may not
provide enough leverage. In general, it's worthwhile to take
your bike to a shop and have the straightening done with professional alignment tools.
Bent cages on friction derailleurs can sometimes be
straightened by hand well enough to work. Bent index
derailleurs should be replaced because they rarely work well
once they've been damaged. If you try to straighten your
derailleur, support the body so that it does not get twisted out
of shape while the cage is being bent into shape. Work
carefully; you don't want to overbend the cage. Bent
derailleur bodies are troublesome. They're very difficult to
straighten. If it can be done, it's a job best left to a shop
mechanic. Otherwise, its best to replace it.
Cleaning
A rear derailleur has few working parts but it is important to
keep the unit clean.The grit that builds up on the outside of
the derailleur body also works its way into the bearing surfaces. Once inside, the grit acts like sandpaper and cuts into
the bearing surfaces, causing premature wear. This wear can
be seen as play, or slop, in the mechanism, which means poor
shifting. Remember, with derailleurs, stiffness is important for
good performance.
A dirty rear derailleur should be cleaned before lubricating. When a bike is being ridden often, it's a good idea to
occasionally give the chain and both derailleurs a thorough
cleaning and lubrication. On mountain bikes, it might be
necessary every month. Road hikes are ridden in a cleaner
environment, so they don't pick up grime as quickly, and for
them cleaning every 6 months is probably sufficient. Let
appearance be your guide. If the drivetrain is covered with
grease, grime and dirt, it needs cleaning.
You can either clean the drivetrain parts on the bike or
remove them for cleaning. To clean them on the bike, remove
the rear wheel and insert a long screwdriver through the rear
dropouts so that it supports the chain. Use a stiff bristle brush
and diesel fuel to clean the chain, derailleurs and crankset.
If you want to disassemble the drivetrain to clean it, begin
by loosening the rear derailleur's cable anchor bolt and
pulling the cable free. Then remove the chain using a chain
tool (see page 152). Unbolt the rear derailleur from its hanger
and remove it from the bike. Put the rear derailleur and the
'Alain in the solvent and let them soak briefly. Use a brush to
:lean the grit out of the chain and the working parts of the
derailleur, then wipe them clean with a rag. Allow the solvent
to dry completely before proceeding.
Lubrication
[f you removed the derailleur and chain, reinstall them in that
Drder. Flush dirt out of the last segment of the derailleur cable
housing with a light aerosol solvent like WD-40 and then
apply a lubricant, such as Pedro's Extra Dry, to the derailleur
p
ivots, cage pivot(s), pulley centres and chain. Pedal backwards
is you lube the chain to allow the lubricant to work its way
into the chain. It's not important to apply lubricant directly to
:he pulley teeth, chainrings or cogs.They will receive all the oil
:hey need from contact with the chain. Shift through the gears
:o work the lube into the derailleur's moving parts. Once you
are satisfied that the derailleur and chain are thoroughly lubri:ated, wipe off any excess oil with a clean rag before it has a
:hance to attract dirt.
Cable and Chain Adjustments
When installing a new derailleur, you must make sure that the
:hain is the right size for your particular combination of
lerailleur, chainring and cassette. Operate the shifter to put
1 90 ILLUSTRATED BICYCLE MAINTENANCE
the derailleur in the small cog position. Place the chain on the
smallest cassette cog. Loosen the cable clamp bolt at the
derailleur, and thread the end of the cable through. Pull the
cable to remove slack; pull it taut, but not tight. While holding
the cable taut with a pair of pliers, tighten the clamp bolt to
secure it.
Shift onto the largest rear cog and the large front chainring. The derailleur cage should be pulled forward almost as
far as it is capable of travelling. Once you have done this, shift
to the small-cog/small-chainring combination to see if there
is any slack in the chain. If the derailleur is not near its limit
in the first combination but the chain is loose in the second,
shorten the chain by removing links. Judge how many to
remove by how much slack you find in the chain.
Conversely, if the chain binds because it is not long
enough to fit in the large/large combination, add chain links.
You may find that you have to make a compromise between
having enough chain for the large/large combination and
avoiding excess slack in the small/small position (or the small
cog/middle chainring on a triple-chainring crankset).
If you have insufficient chain for the first combination and
accidentally try to shift into it, you risk pulling the rear wheel
right out of the dropout. On the other hand, if you have too
much slack in the second combination and happen to shift
into it, you risk having your derailleur bend back over on
itself in an attempt to take up the slack. This could cause the
chain to rub against itself and be damaged. The best way to
avoid these problems is to provide enough chain for the
large/large combination and use a rear derailleur capable of
handling the slack when you shift into the small/small combination. Switching to a rear derailleur with a wider range
will also give you the freedom to switch back and forth
between wheels with different cassette cog combinations,
should you desire to do so.
Installation
Most of what is involved in the installation of a new rear
derailleur is identical to what must be done when installing
and adjusting an old one after removing it for cleaning. However, some of the adjustments discussed are even more critical
with a new derailleur than with an old one.
From the factory, the limit screws will almost certainly be
incorrectly set for your frame and cogset, even if you've purchased the same model you had before. And since the body of
the new derailleur may be different than that of the old one,
the shift cable and cable housing may have to be lengthened
or shortened to get a smooth bend where the cable goes from
the stay stop to the rear derailleur.
Adjustments
Because the location of the wheel can affect the derailleur's
performance, the place to begin your derailleur adjustment is
by considering the position of your wheel in the frame. Most
modern bikes have vertical dropout on which the axle simply
sits in the bottom of the dropouts.
You might have a bike with dropouts with horizontal slots
on which the axle can be positioned in various spots. Index
derailleurs work best if the axle is positioned towards the front
of the dropout. This is also true of Simplex-type derailleurs
(older type) with spring-loaded upper derailleur pivots. Friction rear derailleurs work well with the wheel centred in the
dropout slots.
Range of Motion
Once the wheel is properly positioned, set the range of
motion for the derailleur. Start by adjusting how far the
derailleur can move to the inside (towards the spokes). Shift
into low gear (large rear cog, small front chainring). Adjust the
low-gear adjusting screw, also known as the inner limit
adjusting screw (usually the upper or furthest to the rear of
the two adjusting screws) so that the pulleys are centred
beneath the largest cog.The adjustment is correct when chain
noise is at a minimum and the chain shifts onto the cog
without hesitating and without going over into the spokes.
Now set the outer throw. Shift into high gear (small
cog/large chainring). Adjust the high-gear adjusting screw,
also known as the outer limit adjusting screw, so that the pulleys are centred beneath the smallest cog and the chain shifts
quickly onto the cog. If the chain doesn't shift onto the small
cog easily, loosen the adjusting screw to let the derailleur
move a little further out.
Finally, if you have a single-pivot derailleur with an angle
adjustment screw, set the derailleur so there is about 5 mm of
clearance between the teeth of the jockey pulley and the
teeth of the largest cog when in that gear.
Index Barrel Adjustment
With index (click) derailleurs you must fine-tune the
derailleur so that it moves the chain to a new cog with each
click of the lever. Otherwise, the chain will not land perfectly
in gear and will run noisily.
Because index shifting is so dependent on precise cable
adjustment, index derailleurs have an adjustment barrel that
makes adding or releasing cable tension very simple. The
barrel is located where the cable enters the rear derailleur and
has a knurled ring (usually made of plastic) to make turning
by hand easy. Some shifters have adjusting barrels on the
levers too, which makes adjustment easy even while riding.
The same is true for brake-lever shift levers, which have
adjusters on the downtube housing stops that can be used to
adjust cable tension if needed.
Use your right hand to shift to the smallest cog while
turning the crankarm with your left. Then shift one click to
the second-smallest cog. The chain should instantly move to
REAR DERAILLEURS 191
it and stay there. If it does not advance, turn the barrel adjuster
anticlockwise a quarter-turn at a time until the system shifts
quickly and precisely. If the chain moves too far, you'll hear
noise as it brushes against the third-smallest cog. In that case,
turn the adjustment barrel clockwise a quarter-turn at a time
until the chain runs quietly.You can check the adjustment by
shifting through all the gears.
If gear changes become less precise with time, the remedy
is usually as simple as turning the barrel adjuster anticlockwise
a quarter-turn or so to increase cable tension.
TROUBLESHOOTING
P
ROBLEM: You shifted into the rear wheel and trashed
he rear derailleur. How do you ride home?
Separate the chain with your chain tool
you did bring one along, didn't you?), extract it from the
lerailleur and rejoin the chain on the middle chainring and
:assette cog. Pull the derailleur out of the spokes, straighten
he wheel and ride home on your one-speed.
i OLUTION:
Modifications and Accessories
P
There are very few modifications that can be made on rear
derailleurs. Some companies make special lightweight aluminium or titanium pivot bolts that replace the steel ones
found in some of the more popular racing derailleurs. This
does lower the weight slightly, but it also makes the derailleur
a little more flexible.
Several manufacturers offer sealed-bearing derailleur pulleys. These pulleys offer low rolling resistance and are sealed
so you don't have to service them.
Most rear derailleurs don't require spoke protectors. However, there is always the danger that if your bicycle falls on its
right side, your derailleur could get caught in the spokes. Also,
if the derailleur hanger gets bent inwards, your derailleur
could shift past the large cog. If the derailleur passes the large
cog and gets caught in the spokes, it will probably ruin the
derailleur and could damage the wheel and the frame.You can
minimize this danger with a spoke protector.
Because of the conditions to which they are subjected,
touring bicycles and mountain bikes are more likely than
other types of bikes to suffer a bent derailleur. Spoke protectors are therefore recommended for these bikes.A plastic protector will not rust and makes less noise than a metal one. To
install a spoke protector, remove the cassette or freewheel,
slide the protector over the cassette body or hub threads and
up against the spokes, then replace the cassette or freewheel.
The rear derailleur is a marvellous invention, one that has
helped make the bicycle into an incredibly efficient and
enjoyable vehicle to operate. Install a derailleur model that is
designed to fit your bike and its other components, keep it
clean, well adjusted and properly lubricated, and you will be
rewarded by many miles of smooth shifting performance.
l uite
shift the lever, but the derailleur doesn't
shift into gear and there are a lot of clicking
Raises as you pedal.
ROBLEM: You
iOLUTION: The derailleur may be bent. Have it checked.
f it's not bent, the cable tension has probably changed.
f the shifting hesitates when moving to larger cogs, turn
he adjusting barrel in quarter-turn increments towards the
arge cogs. If shifting to smaller cogs is the problem, turn the
)arrel towards them.
P
ROBLEM: You broke the shift cable and cannot shift
nto an easy gear to get home.
i OLUTION: Pedal
so that the derailleur shifts onto the
mallest cog. Pull on what's left of the shift cable to remove
lack, and attach the upper end beneath a bottle-cage screw.
\low you can shift by pulling on the cable (but you'll have
o hold it to keep the bike in gear). Or, you can pull the
:able to shift into an easy gear and tighten the bolt to hold
t in place.
P
ROBLEM: The rear derailleur makes a constant
queaking noise.
i OLUTION: The
pulleys are dry and need lubrication.
Fry dripping some lube on the sides. If that doesn't work,
lisassemble the pulleys (one at a time), grease the bearing
urfaces and then reassemble.
P
ROBLEM:
Shifting is difficult.
i OLUTION: Dirt may have penetrated the cable and
lousing. Shift onto the large cog, then move the shift lever
)ack to create cable slack. Lift the housings out of the stops,
lide them down to expose the cable, oil or grease the cable
and then reassemble the housings.
1 92
ILLUSTRATED BICYCLE MAINTENANCE
Rear Derailleur Removal and
Installation
1
The rear derailleur is positioned beneath the cassette and is fastened
by a bolt to a hanger, which is suspended beneath the right rear
dropout (see photo). The dropouts are the slotted metal pieces located
at the junction of the seatstays and chainstays. Their function is to hold the
axle of the rear wheel.
The derailleur hanger on an inexpensive bicycle is usually a separate
piece held on the right rear dropout by means of the wheel axle and
the axle nuts. A small bolt aligns this type of bolt-on hanger with the
bicycle Frame (see photo on page 188). The hanger on a higher-quality bike
is usually integrated into the right rear dropout itself (see photo). An integral
hanger contributes to better shifting by being stiffer than a bolt-on hanger.
Some integral hangers, such as the one shown here, feature replaceable
sections that prevent major frame damage if you bend the derailleur badly.
3
Before removing a rear derailleur for cleaning or replacement, you
must free it from both the shift cable and the chain. Removing the shift
cable is simple: Just loosen the bolt that fastens it to the body of the
derailleur and slip it out.
Freeing the chain from the derailleur can be done in one of two ways. One
way is to use a chain tool to break a link in the chain, then pull one end of
the chain free from the derailleur cage (see photo). Do not try to pull through
the derailleur the end of the chain with the rivet protruding from the broken
link. The rivet will catch on the cage. Pull the other end through. Removing
the chain makes sense if it needs cleaning or replacement.
REAR DERAILLEURS 193
/I The other method of freeing the chain is to use a hex key to loosen the
i-bolt that holds the idler pulley on the derailleur (see photo). Remove the
idler pulley so the chain can be lifted off the jockey pulley and clear.
You may need to move the derailleur cage plates apart to free the chain. The
derailleur can then be unbolted from the hanger and cleaned or replaced.
When installing a rear derailleur, follow the same procedure in
reverse. Bolt it back onto the hanger, then replace the chain and shift
--._ cable. Before tightening the cable, however, put the wheel back on the
bike and make sure that the chain is positioned on the smallest cassette cog so
the derailleur is free to move to its outer limit.
Operate the shift lever to make sure it's in its starting position, which will give
the cable all the available slack. Then thread the cable through the anchor on
the derailleur body. Hold the cable taut with a pair of pliers while tightening
the anchor bolt with a hex key.
_
6
.......
.......
-........
After installing a new rear derailleur, check its range of motion and
adjust it properly. Even if you are only remounting your old derailleur
after a cleaning, it is a good idea to check the adjustment. Before finetuning the derailleur, make sure that the wheel is properly positioned on the
frame. If the dropout allows, place the axle towards the front of the dropout,
or just seat it fully in vertical dropouts. Some bicycles come with adjustable
screws to stop the axle when it is in the proper position.
1 94
ILLUSTRATED BICYCLE MAINTENANCE
Rear Derailleur Cleaning and
Lubrication
1
The various components of a bicycle's gearing system are subjected to
a lot of stresses and strains, which are made worse by the accumulation of road or trail grime. The lubricants used to help keep moving
parts working smoothly can also have the opposite effect by collecting dirt that
clogs up and accelerates wear in those parts. This is why the chain, chainrings,
cassette cogs and both derailleurs need frequent cleaning and lubrication.
One way that you can tell when a rear derailleur is in need of a cleaning
is by pushing it in with your hand (see photo). If it's difficult to move and
sluggish about springing back out, assume that it has grit in its pivots and
needs to be cleaned.
2
To give a rear derailleur a truly thorough cleaning, take it off the
bike. While you're at it, remove the wheel and clean the cassette
cogs. Also thoroughly clean the chain and the chainring teeth. All
these components interact in such a way that grit accumulated on one is
quickly passed on to the others.
To remove the chain from the derailleur without breaking a link, remove the
idler pulley from the rear derailleur chain cage (see photo). One advantage
of this is that it enables you to more easily clean the pulley and chain cage.
In fact, you may want to remove the jockey pulley as well. This will make the
cleaning and lubrication process easier and more thorough.
.
3
_.
.
Loosen the shift cable and unbolt the derailleur from the bike. Soak
the metal parts in a safe solvent to loosen the grime. Use soap and
water or a mild solvent on the plastic surfaces of the pulleys. Take the
derailleur out of the solvent and scrub it with a small brush, such as an old
toothbrush (see photo). Rinse off the residue with the solvent and wipe the
derailleur clean with a rag. Let it air-dry so the solvent can evaporate.
REAR DERAILLEURS 195
4
Fasten the derailleur back on the dropout hanger. Before replacing
the pulleys, coat their bushings with a light coat of grease (see photo).
Replace the chain before putting the idler pulley back on. Before
hooking the shift cable back to the derailleur, wipe down the section of
cable that runs through housing, and flush the dirt out of the housing with
an aerosol solvent like WD-40. Thread the cable through the anchor on the
derailleur and hold it taut while tightening the bolt.
5
Drip a small amount of general-purpose lubricant, like Pedro's Extra
Dry, into each point where the derailleur pivots (see photo). Use the
shift lever to move the derailleur back and forth. This will help spread
the lubricant over all bearing surfaces and will help you tell when enough
lubricant has been used (it doesn't take much).
...
6
„....
.„,.._
After you have applied the lubricant and worked it into the inner
surfaces of the derailleur, wipe away any excess clinging to the
outer surfaces — it will only serve as an unneeded trap for fresh grit
(see photo). Once the cleaning and lubrication is complete, replace the rear
wheel and adjust the derailleur following the instructions on page 196.
1 96
ILLUSTRATED BICYCLE MAINTENANCE
Rear Derailleur Adjustment
1
Place the bike in a repair stand. Check derailleur adjustment by pedalling with your right hand while pushing on the derailleur with your
left. Adjust the inner throw of your rear derailleur first. Shift the chain
onto the largest cog. It should seat quickly on the cog. If it hesitates or goes
over the cog and into the spokes, adjust the derailleur with the low-gear
adjusting screw. Anticlockwise turns allow the derailleur to move further
towards the spokes. Clockwise turns limit travel.
2
Shift the chain to the smallest cassette cog. Turn the high-gear
adjusting screw until the pulleys line up beneath the small cog
(see photo). With your bike still mounted on the repair stand, spin the
crankarms around and run through the gears. Pay special attention to how
well the chain shifts onto the largest and smallest cogs (that you used to set
the derailleur adjustments).
If there's any hesitation in these shifts or a lot of clatter in the rear after the
shifts – or any sign that the chain may jump off the cogs – fine-tune the
adjustments until the shifts become quiet and accurate. If you don't have a
repair stand, take the bike out for a spin to check the adjustment.
3
Some derailleurs have a third screw called the B-tension screw or
the B-angle screw (see photo). This adjusts the clearance between
the jockey pulley and the cogs. On single-pivot derailleurs like those
manufactured by SRAM, the B-angle screw is used to directly adjust the distance between the jockey pulley and the largest cog. This distance should be
about 5 mm – close enough for quick shifting, but clear enough that the chain
can pass freely from the second-largest cog to the largest.
Double-pivot derailleurs rely on a spring inside the B-knuckle to actively
adjust the cog/jockey clearance for each gear. The ideal setting can be a bit
elusive. Adjust the B-tension screw so the pulley rides as close to the cogs as
is practical without making noise in any gear.
REAR DERAILLEURS 197
4
After installing a new rear derailleur or changing chainrings or
cassette cogs, you may need to alter the chain length in order for the
derailleur to shift properly. The chain should be long enough so that
it will easily go onto the largest chainring and the largest rear cog. (This is
not a recommended gear because of the extreme chain angle it creates, but
it is useful for checking chain length.) Conversely, when the chain is on the
smallest chainring and the smallest cog (another gear that is not recommended), there should not be excessive slack in the chain.
• 31!Id.^,
5
Fine-tune the derailleur so that it moves the chain to a new cog with
each click of the shift lever (unless you have an older bike with friction
levers). Do this with the adjustment barrel. Use your right hand to shift
to the smallest cog while turning the crankarm with your left. Shift one click.
The chain should instantly move to the second-smallest cog and stay there. If it
doesn't, turn the barrel adjuster anticlockwise a quarter-turn and try again.
Continue to turn the barrel until shifts are quick and precise. If you go too far,
the system will run noisily. In that case, turn the barrel clockwise a quarter-turn
at a time as you pedal until the noise stops. As a final check, shift through all
the gear combinations, making sure that the system works quickly and quietly.
6
When a bike falls over or gets hit on its right side, the rear derailleur
can be damaged. Fortunately, the most likely damage, a bent
hanger, is not expensive to repair. You might even be able to fix it
yourself. If your derailleur-fastening bolt has a hex head, insert a hex key into
it and use it and the derailleur body to lever the hanger back into line (see
photo). Relying on the hex key alone may cause damage to the derailleur pivot
bolt or the key itself, so be sure to to put a hand behind the derailleur and pull
with it as you pull up on the bolt with your other hand. Have a pro mechanic
perfect the 'adjustment'.
CHAPTER 12
Headsets
Headsets are often overlooked when the time comes for
regular maintenance. Maybe this is because headsets are so
inconspicuous, but the fact is that a headset's function is so
subtle that it often goes unnoticed only until something is
drastically wrong. Unfortunately, when something does go
wrong with your headset, precise steering can become difficult or even impossible.
A well-maintained, properly adjusted headset, on the other
hand, will yield years of trouble-free service. Properly cared
for, your headset will gladly let you sit back and enjoy the
scenery while it sits quietly outside the spotlight, just getting
its job done.
What exactly is a headset? Basically, it's the component that
connects the fork to the frame and allows the fork to turn for
steering. It's also forced to withstand the massive pressures
encountered when the fork transmits shocks into the frame,
such as on a rocky descent.
The headset must do all this without adversely affecting
the handling of the bicycle. Certainly, the headset is not
the only component that influences bike handling, but it's
no less critical than the rest. A poorly installed, adjusted or
maintained headset can make even the finest bicycle difficult
or awkward to handle.
Some symptoms of a neglected headset are a loose feeling
in the handlebar or rattles and clunks coming from the fork
when riding over bumps. Another problem is the inability to
travel in a straight line when your hands aren't
steering. Still another is when the handlebar
turns but you feel it catch as if there were notches stopping
the turning at various points through the fork's rotation inside
the head tube. These problems indicate the necessity for
headset maintenance or overhaul.
Types and Basic Parts
The most common kind of headset uses a cup-and-cone
bearing arrangement. Two sets of cups and cones, one
between the fork and head tube and one on top of the head
tube, work together to hold the fork and allow it to turn in
relation to the frame. The upper cone and lower cup are
attached to the head tube of the frame. The lower cone and
upper cup are attached to the steering column of the fork. A
set of bearings — either loose or in a retainer — separates each
cup and cone, allowing the steering column to twist within
the head tube. (Each set of cup, cone and bearings is referred
to as a `stack'.) This is the conventional headset, the type most
commonly encountered.
In recent years, a number of sealed-bearing headsets have
appeared, both as standard equipment on new bikes and as
replacement units for older bikes. Also, there have been a
number of exotic designs on the market that tried a variety of
concepts, such as interlocking Teflon sleeves or single-axis
roller bearings, in an attempt to improve a headset's ability to
do its job. It's unlikely that you'll ever stumble upon these
exotic variations, since they were usually plagued by more
problems than they solved and were replaced.
Because there are forks with threaded and
Chris King Devolution
Chris King
Cane Creek Double X headset for
Shimano XTR
headset, for using 11/8-inch
NoThreadSet headset
OnePointFive standard bikes
threaded headset
Generic threaded headset
forks in 11/4-inch headtubes
The most common sizes of headsets found on bikes today are 1- and 11/4-inch
Replacement parts for these are difficult to find now, but Chris King
threaded, and 1-, 11/4-, and 11/4 -inch threadless. For a short time, 11/4-inch,
components make it possible to use a 1% -inch fork on frames built for
among other sizes, were experimented with by some manufacturers.
the obsolete 11/4-inch headset size.
200 ILLUSTRATED BICYCLE MAINTENANCE
nsic e Your Headset
KEYED WASHER
UPPER CONE
N
6N.N.
UPPER CUP
RETAINER
RING
UPPER CONE
RUBBER
SEAL
CARTRIDGE ■
BEARING
■ LOWER CUP
CROWN RACE
7/4J
CROWN RACE
ThreadleEs Headset
Threaded Headset
HEADSETS 201
threadless steerers (the steerer is the column at the top of the
fork that the headset attaches to), there are also threaded and
threadless headsets. Today, threadless headsets are found on
nearly all mountain bikes, most higher-quality road bikes and
even many midpriced hybrid and comfort bikes.
A threadless headset is adjusted differently to a threaded
one. All that's needed is a hex key or two. In fact, a threadless
headset is quite simple to adjust, disassemble and overhaul
compared to a threaded one. One big difference, though, is
that it requires a different stem, and this stem is integral to the
adjustment of the headset. A threadless stem locks the adjustment of the headset by tightening to the outside of the fork.
A variation on the threadless headset is the integrated
headset. Integrated headsets forego the separate bearing cups
that are pressed into the frame on a standard headset. Instead,
sealed cartridge bearings are fitted directly into an enlarged
headtube. The rest of the components remain the same as
most other threadless headset designs.
What Makes a Headset
Like the crankset and the wheel hubs, the headset on a
bicycle is not simply one component but a series of separate
parts that function together as one system. Despite variations
in design, all headset systems employ a similar combination of
parts. Working from the top down, the typical threaded
headset is made up of the following parts, which are shown in
the exploded-view illustration found opposite.
1. locknut (this is tightened to secure the adjustment)
2. lockwasher (this keeps the headset from loosening)
3. adjustable cup (this is turned to adjust the headset)
4. bearing retainer
5. top head race
6. lower head cup
7. bearing retainer
8. fork crown race
Some threaded headsets also have a reflector bracket or a
centrepull brake cable hanger that fits between the locknut
and the lockwasher.
Threadless headsets typically are made up of the following
parts (from the top down):
1. adjusting bolt (this is for adjusting the headset after the
stem is loosened)
2. top cap
3. recessed seated nut (this is inserted inside the fork
column)
4. stem (this is clamped to the fork to lock the bearing
adjustment)
5. spacers (these can be placed on top of or beneath the
stem, or even removed)
Integrated headsets function just like threadless headsets with one
difference: instead of separate bearing cups that are pressed into the
head tube, integrated headsets use cartridge bearings that fit directly
into a specially designed head tube.
6. washer
7. bevelled lock washer
8. cup
9. bearing retainer
10. top head race
11. lower head race
12. bearing retainer
13. fork crown race
Buying a Headset
Generally, if you're shopping for a new headset, the conven:ional cup-and-cone models are a good choice because
:hey're affordable, simple in design, easy to maintain and easy
:0 service.
Some headsets are called sealed-bearing models. On
:heaper ones, the bearings are shielded by the addition of a
Plastic seal or rubber 0-ring in the openings between the
:ups and cones. Sometimes, interlocking pieces form a
abyrinth as a shield: the dirt must work its way around the
Farriers before it can get into the bearings. Both shielding
:echniques work quite well and have no detrimental effects
an a headset's performance, nor do they make servicing any
nore difficult.
Then there are the most expensive and most impressively
lesigned headsets, which employ true sealed-cartridge bearngs, such as Chris King headsets. Servicing a King headset is
202
ILLUSTRATED BICYCLE MAINTENANCE
CANE CREEK INTEGRATED HEADSET
CAMPAGNOLO RECORD HIDDENSET
INTEGRATED HEADSET
FSA ORBIT INTEGRATED HEADSET
CAMPAGNOLO HIDDENSET
INTEGRATED HEADSET
Integrated headsets vary slightly in dimension — so slightly that the differences
often cannot be detected by the naked eye. Check specifications with the
manufacturer of your frame and of your headset before beginning installation
or the results could be disastrous.
as simple as popping off a couple of seals and squirting in
some fresh grease on occasion. We've even seen a few neglected King headsets that still perform flawlessly after nearly
20 years. Someone once said, 'You rent a headset; you buy a
King', and it's possible that truer words were never spoken.
If a true sealed-bearing headset does develop problems, it's
usually easy to get replacement bearing cartridges, depending
on the model. Check the owner's manual, the manufacturer's
Web site or a shop for advice.
A few cup-and-cone headsets use tapered roller bearings
rather than ball bearings. If you dismantle your headset and
find that the retainers contain what appear to be small cylinders rather than balls, these are tapered roller bearings. The
load-bearing points of contact are larger on roller bearings
than on ball bearings, and this can extend the life of the roller
bearing units by spreading the load over a wider area. The
only problem with this system can be trying to find replacement bearings when the time comes. If you can't find them,
you'll need to replace the headset.
If you're considering replacing your present headset and
are thinking of changing to a different brand or model,
choose one of the many conventional ball-bearing headsets.
The reliability of these units is hard to beat, and they're
affordable. If you aren't interested in upgrading to a 'better'
headset, try to get the same brand and model that your bike
originally had. This way, you won't have to worry about
whether it will fit your bike.
There are a variety of headset sizes, and it's important to
match a new one to the old to ensure that things will fit.You
can take the frame, fork and headset to the shop for comparison if you are unsure.
Making Headset Seals
If you wish to shield your nonsealed headset, you can do so by
covering the opening between the cup and race of the upper
and lower stack with a piece of rubber. Cut a section of inner
tube, about 3 to 4 cm (1 to 1XL inches) long, to form the shield.
It's usually necessary to disassemble the headset before you can
install this rubber doughnut over the lower stack. Only the
stem needs to be removed to install such a shield over the
upper stack. Usually, people cover only the lower part of the
headset (the part between the fork and the frame) because it
receives the most dirt and crud from the road.
If you frequently transport your bicycle on the roof of
your car, you may be blowing the grease out of your
headset bearings. The 100-km/h (65-mph) wind can get
through the openings between cups and races and blow the
grease out onto the frame. This not only makes a mess, but
also you lose the corrosion protection and lubrication from
your bearings. Using a headset shield will stop this from
happening. If you don't install such a shield, at least wrap a
piece of plastic around the head tube when transporting the
bike on your car.
Adjustment
If your headset seems either loose (you hear a clunking sound
and feel a looseness from the front end when riding over
rough roads or trails) or tight (the steering binds and sounds
crunchy, and it's difficult to ride no-handed), you can usually
remedy the problem with a simple adjustment. It may take
several tries to get the adjustment right, so don't get discouraged if it's not perfect after the first attempt.
If your headset is a threadless type, adjustment couldn't be
simpler. All it takes is a hex key or two.The headset parts slide
onto the fork (instead of being threaded on, as on threaded
designs), so you only need to loosen the bolts that are
clamping the stem, tighten the adjusting bolt on top of the
stem (or loosen it if the adjustment is too tight) and retighten
the stem bolts to lock the adjustment in place.
Threaded headsets are more difficult to adjust. The only
tools needed are spanners that are large enough to fit the flats
on the locknut and the adjustable cup. Headset spanners make
the job easy, but they're not absolutely essential. A large
adjustable spanner works fine for the locknut. Use a pair of
adjustable pliers to hold the adjustable cup if it's steel, but wrap
a rag around the cup to protect its finish. Some adjustable cups
have serrated edges to make it easy to turn them by hand.
If the exposed headset parts are made of aluminium,
purchase the proper spanners to fit the spanner flats on the
locknut and adjustable cup. Otherwise, you'll probably damage
:hese parts when you attempt to tighten and loosen them.
Adjust a threaded headset by turning the locknut anti:lockwise to loosen it. If the headset was too tight, loosen the
adjustable cup by turning it anticlockwise a fraction of a turn.
HEADSETS 203
If the headset seemed too loose, tighten the adjustable cup by
turning it clockwise. Turn the adjustable cup down until it
contacts the bearings, then back off the adjustment oneeighth to one-quarter turn. Now, while holding the
adjustable cup in position, tighten the locknut by turning it
clockwise.
To see if your headset needs adjusting or to check an
adjustment you've made, grasp the front fork with one hand
and the frame with the other. Alternately push and pull the
two towards and away from each other. Do the push-pull
check with the fork turned to several different positions. For
threadless headsets, if you feel any looseness at any position of
the fork, once again loosen the stem and snug the top bolt to
remove play. For threaded headsets, loosen the locknut and
turn the adjustable cup clockwise, then tighten the locknut.
When done, repeat the push-pull test.You can also check
the headset by picking up the front of the bike and dropping
the front wheel onto the ground while gently holding the
stem. If you hear or feel anything rattle, the headset is still
loose. Another method is to apply the front brake and push
and pull the bike back and forth, checking for a knocking
sensation that would indicate play in the headset.
Make a second check of the headset by lifting the front of
the bike and slowly turning the handlebar to see if the bearings bind, causing resistance, at any point in the rotation. If the
headset binds, loosen the adjustment a bit by turning the
adjustable cup anticlockwise on threaded headsets, or loosening the stem bolts and backing off the top nut slightly on
Fit short sections of an inner tube over the ends of the head tube during a
headset overhaul, then pull them over the cups later to shield the bearings
from wind and road grime.
threadless systems. Don't be discouraged if it takes a couple of
tries to get the adjustment where there is neither binding nor
play in the headset. If you feel you cannot get it adjusted so
it's just right — that is, not tight and not loose — adjust it so
that it is slightly tight.
Double locknut (on threaded headsets only). Some headsets have two locknuts. The extra locknut helps in the initial
assembly of the bike but does not provide any substantial benefit to the rider. The second locknut usually resembles a
threaded washer with two or three notches in it, and it sits
beneath the top locknut. If you work on a headset with two
locknuts, you must loosen both before attempting to adjust
your headset. To loosen the second locknut (the lower one),
it is often necessary to use a hammer and punch. Retighten
the top locknut when all the other steps are completed.
If you wish to eliminate this second locknut, thus simplifying any future adjustments, you can do so by replacing it
with extra headset lockwashers to take up the space it occupies.You can get these extra washers from your bike shop.
Overhaul
As part of a regular maintenance program, road bike headsets
should be overhauled every year and mountain bike models
every 6 months if they're used off-road. There's no quick way
to overhaul a headset; but after you've done it a couple of
times, you'll find that it's not that difficult. For this job, you'll
need the same tools you used for headset adjustment. The
only additional tools necessary will be those required to
loosen the stem (usually, a 5 or 6 mm hex key will do the job)
and a tool to loosen the brake.
You'll also need some medium-weight grease and new
bearings.Your shop mechanic may know what bearings fit in
your headset, or you can just take in the old ones to match up
the new ones.
Why buy new bearings? Because with use, ball bearings
cease to be completely round, making proper adjustments difficult to impossible. If yours are nice and shiny, in like-new
condition, reuse them. If they're tarnished, rusty or pitted,
replace them with new ones of the same type.
Before you begin the process of rebuilding your headset,
spread an old sheet below your bike to catch any stray bearings that might fall on the floor. Put the bike in a repair stand
or hang it so the front wheel is suspended.
Remove the front wheel. For road bikes, remove the front
sidepull brake by unscrewing the nut that holds it to the fork.
For mountain bikes, unhook the link wire (on a cantilever) or
lift the noodle out of its holder (on a direct-pull) to release
the brake. Unscrew the bolt from the side of the brake that's
attached to the cable to remove it from the fork (keep the
parts together with a rubber band or tape).
204 ILLUSTRATED BICYCLE MAINTENANCE
Threadless headsets. For threadless headsets, disassembly is
usually simple. Remove the adjusting bolt on top of the stem
and extract the top cap. If the top cap is stuck (as plastic ones
sometimes are), carefully pry it off the top of the fork with a
screwdriver.You may also run into a complicated top cap that's
made up of several pieces. Usually, loosening the top bolt will
allow removal.You may need to tap the top of the cap to loosen
the unit. If it won't come out, don't force things; check the
instructions in the owner's manual or the headset instruction
manual, or check with a shop mechanic for help.
Once the top bolt and cap are off, hold the fork so that it
can't fall out, loosen the bolt or bolts securing the stem and
slide the stem off the top of the fork.You'll now be able to lift
the parts off the fork and extract the fork from the frame.
Sometimes the fork won't come out after removing the
stem because the headset parts are stuck. If this happens, try
tapping the top of the fork with a plastic mallet to knock the
fork out. If tapping doesn't move it, hit harder until it comes
out, but be careful not to damage the fork (and make sure you
don't miss and hit the frame).
Threaded headsets. For threaded headsets, loosen the stem
by turning the expander bolt (on top of the stem) anticlockwise. Turn the bolt two or three full turns, and then hit it on
the head with a hammer. This knocks loose the expander
wedge at the base of the stem (inside the fork), which is
holding the stem tight.
If the stem hasn't been loosened in a long time, it may take
more than one blow to make the stem binder wedge inside
the steerer tube drop free. However, it's best not to strike the
binder bolt directly unless you use a plastic mallet. Otherwise,
place a small block of wood over the bolt before hitting it.
(Put on goggles first in case the wood shatters.)
Dealing with a frozen stem. If the stem bolt is loose but the
stem won't come out, it's probably corroded inside the fork.
If you're lucky, you'll be able to muscle it out. Put the front
wheel in the fork, clamp it between your knees and turn the
bar from side to side to loosen and extract the stem. If it's
really stuck, remove the wheel, carefully clamp the fork crown
in a vice and wrestle the stem out with the bar.
If these measures don't work, turn the bike upside down
and spray a penetrating solvent down the fork steerer so it can
pool on top of the stem wedge and penetrate. Let it sit for a
day, then try again; repeat until it's possible to remove the stem.
Tapping on the stem will help the solvent penetrate the
corrosion.You can also try heating the stem with a propane
torch, but do this carefully and only in a well-ventilated area
because the fumes can be hazardous to breathe. If you're patient
enough, the penetrating solvent will eventually break the bond
and allow the stem to be removed. It may take some time,
though — even days!
Once they're loose, lift the handlebar and stem unit out of
the steering tube. Hang it on the top tube because cables
will still be attached. If you wish to remove the handlebar
completely, you'll have to detach all the cables.
Remove the headset locknut by turning it anticlockwise.
If you have a headset with two locknuts, remove the second
locknut as well. Slip off the lockwasher, the reflector bracket,
the brake cable hanger and anything else you find positioned
above the adjustable cup.
While holding the front fork from underneath, spin the
adjustable cup off by turning it anticlockwise. Be careful. If
the bearings are loose (not held in a retainer), they might
momentarily stick to the adjustable cup as it spins away from
the top headrace and then fall on the floor. If the bearings are
loose, you may want to take the frame off the stand and tip it
over on its side near the floor before removing the adjustable
cup. When you remove the race, the bearings can fall the short
distance onto the cloth and be controlled. Even though you'll
be replacing them, you need to know how many and what
size were used in each race.
If possible, turn the frame upside down (or at least on its
side) before sliding the fork out of the head tube. If the bike
is upside down, the remaining bearings will be less likely to
drop on the floor since they'll be held in the cup-shaped race
of the lower head cup. Retrieve and save all the bearings. Try
to keep the two sets of bearings separated if they are loose —
some headsets use different numbers of bearings in the upper
and lower races. Clean and count the bearings before taking
them to a bike shop to purchase the proper size and number
of replacements. If you discover any damaged bearings, look
For corresponding damage inside the bearing races.
Most conventional headsets use h,-inch ball bearings, but
;ome use X6- and h-inch bearings. The only way to know for
;ure is to measure them. Take a couple to the bicycle shop to
e sure that you get exact replacements. Even though the difSerence between the sizes may seem insignificant, it's enough
:o make the headset not work. If you're purchasing loose ball
3 earings, buy a few extra because they're very easy to lose.
Clean the adjustable cup, top headrace, lower head cup and
Rork crown race. Inspect them for pits and cracks. If they have
my pits or cracks, all or part of the headset may have to be
Replaced. We will say more about headset replacement later.
ft.eassembling threaded and threadless headsets. Once you
lave new bearings and all the headset components are clean
and in good shape, you're ready to reassemble the headset.
'kpply a heavy coat of grease to the fork crown race, lower
mead cup, top headrace and the adjustable cup. Never be afraid
of using too much grease: any extra will just move out of the
way once the headset is reassembled.
Lightly grease the steerer tube from the fork crown race
dl the way up to and including the threads. (For threadless
HEADSETS 205
headsets, leave the stem clamping area clean.) This will help
prevent any corrosion of the tube and its threads as well as
make it easy to thread on the adjustable cup or slide on
threadless components. If you're using caged bearings, apply a
coat of grease to them as well.
If you're going to use a headset shield, slide the first shield
over the lower head cup. Curl the shield up as high on the
frame as possible so that it won't interfere with the adjustment
of the headset.
Arrange the appropriate ball bearings inside the lower
head cup of the inverted frame. Usually, the bearings are in a
retainer. Be sure that the bearing retainer faces the correct
direction. To determine this, take a close look at the retainer.
There are two types: one has a round profile; and the other
has a flat profile. On both, metal fingers curl around between
balls in a kind of C formation. What we call the 'closed' side
of the retainer is the backside of the circle of little C shapes.
For round-profile bearings, this side of the retainer should
always be set against the cup-shaped bearing surface. This
means that the open side of the retainer faces the cone, and
vice-versa for flat-profile bearings.
If your headset uses loose bearings, put the same number
in as were removed. If you're not sure how many were in
there, put in as many as will fit while still leaving a small gap.
The grease should hold loose bearings in place while you
replace the fork. If you do drop a bearing, clean it off before
replacing it so that dirt doesn't get packed into the headset.
When the bearings are in place, slide the fork carefully all
the way into the frame so that the bearings make full contact
with the lower head cup. Hold the fork in place while you
turn the frame right side up and install the bearings on the
top headrace. Again, if the bearings are loose, use the same
number as were removed and use enough grease to ensure
that they are held in place.
For threaded headsets, spin the adjustable cup down on the
steerer tube until it presses firmly against the upper bearings.
If you have loose bearings, hold the threaded cup and spin the
fork clockwise. This will draw the cup onto the bearings
without disturbing their position. For threadless headsets,
simply slide on the top cup and press on the lockwasher.Then
add any spacers.
For threaded headsets, slide the lockwasher, the reflector
bracket, the brake cable hanger and anything else that came
off the steerer tube back on in the same order they were
removed. After these are in place, thread on the locknut, but
don't tighten it yet. Also put the upper shield in place now, if
you plan to use one. Slide it over the locknut and down as far
as possible so that it won't interfere with the adjustment.
For threadless headsets, you're ready to complete the
assembly and adjustment. Slide on the stem, press in the top
cap and screw in the bolt on top. (If you happen to have a
multipart top cap, see below.) Screw in the bolt until the fork
Use two headset spanners simultaneously to adjust a threaded headset:
one on the locknut (top nut) and one on the adjustable cup (or cone).
turns smoothly and there is no play when you push and pull
on the fork. Then secure the adjustment by tightening the
stem bolts (making sure the stem is centred over the wheel
first), and you're ready to roll.
For threaded headsets, install and tighten the stem because
it can affect threaded headset adjustment.Then, while holding
the adjustable cup in position, tighten the locknut by turning
it clockwise.
Dealing with complicated top caps. During removal we
mentioned complicated top caps on threadless headsets.These
zaps are made up of several parts and are designed to jam inside
:he fork steerer with a wedge action.This differs from the traiitional recessed nut (sometimes called a star-(angled nut)
Found on most threadless headsets, which is pressed into the
Fork with a special tool and remains in place thanks to sprung
:abs around the nut that dig into the walls of the fork.
Complicated top caps are often used on forks with carbon
;teerer tubes (the tube that's inside the frame when the fork
s installed) because the sprung-tab model, which is harmless
rn a metal fork, can cut into the carbon tube, causing a weakless that can lead to failure. The complicated ones, on the
)ther hand, use a gentler mechanical principle. Another
-eason they're used is because they're reusable. (The sprung:ab models, once installed, cannot be easily removed so they're
isually left inside the fork and you must purchase a new unit
• or a new fork.)
There are several types of these complicated top caps, but
:hey're usually installed by assembling them first and then
Biding them as a unit into the fork before the stem is
nstalled. Tightening the bolt should jam the base of the
mechanism inside the fork. Then, unscrew the bolt, remove
206
ILLUSTRATED BICYCLE MAINTENANCE
Adjustment Tips
Let's say that you're very careful, yet you cannot get the
headset to adjust properly. Here are some possible sources of
the problem and what to do about them, plus other important adjustments to check.
1. If the bearing adjustment is always loose or tight and
A common type of wear and tear found on headset cups and cones is
brinelling, which is when the bearings wear a series of dents in the parts
and cause a notched feeling in the steering. When it's really bad, it
almost locks the steering, making it impossible to ride no-handed.
the top cap and install the stem. Finish the job by putting the
top cap on top of the stem, installing the bolt and tightening
until play is removed from the headset bearings. Centre the
stem and snug its bolts.
If the top cap doesn't jam inside the steerer, it will be
impossible to make a good bearing adjustment. Usually the
problem is that the parts of the cap have been assembled in
the wrong order. Study them and determine what order will
cause the lower parts to jam inside the fork when the bolt is
tightened.You can usually figure it out with a little inspection
because it's logical and you're smart. Or, experiment to find
the arrangement that looks right. In most cases, the top bolt
pulls a piece that causes another piece to expand inside the
fork, which causes the base to jam in place.
If you can't figure it out, you might find help in your
owner's manual or the directions that came with the headset.
If necessary, take the top cap or your bike to a shop and ask
for help. For your safety, it's important to make a proper
headset adjustment.
Once the headset is properly adjusted, install the front
wheel and fully tighten the stem. Be sure that the stem is
aligned with the front wheel. Reattach the brake and cable,
and centre the brake over the wheel. If you installed them,
unfold the headset shields so that they fully cover the openings in the upper and lower headset assemblies.
you have a headset with loose ball bearings in it, check
to make sure that you have the correct number of bearings in the upper and lower races. You may have left
some out.
2. If the headset feels tight no matter how you adjust it
and the bearings are in retainers, be sure that the retainer
is properly oriented. If it's upside down, it will cause the
headset to bind.
3. Make certain that the stem is installed properly. Sometimes, the bolt will feel tight but the stem won't be.Try
turning it by twisting the bar, and make sure that the
stem is tight enough that it doesn't move.
4. If the headset binds and you recently crashed, take the
bike to a shop to see if it's bent. If it is, it'll have to be
straightened or replaced. Also, check to see if the steerer
tube is bent. If it is, either the steerer or the entire fork
may have to be replaced.
5. Be sure that all the washers, reflector brackets and
other parts originally on your steerer tube are back in
place. If they're left out, you'll have to replace them or
the headset adjustment may not work correctly.
Fitting a New Headset
If you decide to replace your present headset, it's best — and
usually easiest — to replace it with the same model you
removed. If you're going to install a different model, make
sure that the new headset will fit your frame.Your frame and
fork may have to be modified by a professional mechanic to
accept the new headset.
You'll need the bicycle shop's help in several other areas
as well. Special tools are required to remove the old fork
crown race, the lower head cup or the top headrace without
damaging the frame or fork, as well as to install the new
headset parts. It may be necessary to have the head tube and
the fork crown race cut to fit the new headset components.
Tools for this task are very expensive and require special care
and skill to use.
Have a bicycle shop remove and fit the fork crown, lower
head cup and the top headrace. Attempting to fit a headset
without having the frame properly prepared can damage not
only the headset but the frame as well. Once the fork crown,
Lower head cup and top headrace are installed, you can then
reassemble your headset by following our instructions for a
headset overhaul.
HEADSETS 207
TROUBLESHOOTING
PROBLEM: On a threaded headset, you've loosened the
stem bolt several turns but the stem isn't loose.
Tap the top of the stern bolt with a mallet.
That'll knock free the wedge at the base of the stem (inside
the fork) that's holding the stem tight in the fork. That
should loosen the stem.
SOLUTION:
PROBLEM: Your threaded headset will not stay in adjustment even though you keep tightening the locknut.
SOLUTION: Make sure there's a notched lockwasher
between the locknut and the adjustable cone, and hold
the adjustable cone as you tighten the locknut.
too small for your frame, Chris King manufactures special
headsets that can adapt a 1-inch fork to a VA-inch frame or a
1'A-inch fork to a 1Y,-inch frame. Because of the limited
availability of PA-inch forks, there are several companies
1
frame to the
manufacturing adapters to reduce a 1 /2-inch
1
current standard of 1 /, inches.
PROBLEM: While trying to disassemble a threaded
headset, the adjustable cup turns and turns but will
not come off.
Unfortunately, this usually means that the
adjustable cone and the fork have developed stripped threads.
You may need to replace both.
SOLUTION:
PROBLEM: You
loosen the stem bolts but the stem won't
budge.
PROBLEM: When
you disassemble the fork for overhaul,
the fork crown race is loose on the base of the fork (it
should be tight enough that you cannot remove it by
hand).
Replace it with a tight-fitting crown race, or
try securing the one you have by applying a bit of thread
adhesive to the fork crown and reseating the race. Or, ask a
shop to enlarge the crown race seat on the fork.
SOLUTION:
The stem may be corroded in place.Try carefully and securely clamping the fork crown in a vice and
twisting the bar to break the stem free and wiggle it off.
That didn't work? Apply a penetrating solvent, wait overnight and try again. Still stuck? Keep applying the penetrant
and waiting, even if it takes weeks. Or try carefully heating
the stem with a propane torch.
SOLUTION:
PROBLEM: Your
threaded headset will not stay tight,
even though you keep tightening the locknut.
PROBLEM: On
a threaded headset, you've loosened the
stem bolt and knocked it with a mallet. The stem feels
loose but it won't come out.
SOLUTION: The
SOLUTION:
fork may be too long. Remove the stem
and check to see that there's a small gap between the top
of the locknut and the top of the fork. If not, remove the
locknut and install a spacer, then readjust the headset. (Too
long a fork will mean that the locknut tightens against the
fork instead of against the cone.)
PROBLEM: You've
removed the bolt on the top of your
threadless headset but you can't get the top cap out.
You may not need to remove it.Try loosening
and removing the stem — the cap should come off with it.
Just keep track of the cap (if it falls off the fork) and any cap
parts that are inside the fork.
SOLUTION:
want to install a fork, but the fork's
steerer tube is the wrong diameter for the headset
and frame.
PROBLEM: You
SOLUTION: It may be best to get the correct fork for the
frame. If you absolutely insist on using a fork with a steerer
The stem wedge is probably stuck inside the
frame. Unscrew the stern bolt all the way. Remove the stem.
Take the bolt and screw it back into the wedge, which you
should now be able to see inside the fork. Use the bolt as a
handle to wiggle and remove the wedge. Reassemble the
stem, being sure to grease the parts.
208
ILLUSTRATED BICYCLE MAINTENANCE
Threaded Headset Adjustment
1
When a headset is either too loose or too tight, it should be readjusted
because either problem can negatively affect the steering of the bike
and cause unnecessary damage to headset parts. Severe looseness or
tightness in the headset bearings will probably be obvious to you while riding.
However, there are some simple tests to make while off the bike to determine
whether a headset needs adjustment.
To check for looseness in the headset, stand beside your bike. Hold the handlebar with one hand and the front wheel with the other hand. Alternately
pull the two together and push them apart (see photo).
.
2
If you feel any play in the bearings, the adjustment is too loose. To be
really thorough, repeat this test with the front fork turned to several
different positions. If you discover looseness when the fork is turned
to one position, but not another, that is a sign of possible pitting in one of your
bearing races. In that case, your headset needs to be overhauled rather than
si mply adjusted.
Another method to check for a loose headset adjustment is to lift the front
wheel a few inches off the ground, then let the bike drop (see photo). If you
',ear rattles in the headset area, it's a sign that your bearings are too loose.
3
To check for tightness in the headset adjustment, grab hold of the
handlebar and slowly turn the front wheel of the bike from side to
side (see photo). This is best done with the wheel held slightly off the
ground so that the movement is not hampered by contact between the tyre and
the ground. If you feel any resistance at any point in the rotation of the steerer
tube, loosen your adjustment a bit.
HEADSETS 209
4
Adjusting a headset is not particularly difficult, though it may take
you several tries to get it just right. Begin by loosening the locknut,
which is positioned at the upper end of the steering column. If you
lave a special spanner made to fit your locknut, use it. Otherwise, you can
get by with a large adjustable spanner (see photo) if you are careful not to
'ound the edges of the locknut's spanner flats. Turn the locknut anticlockwise
o loosen it.
adjusta
cup clockwise
the adjustable
until you
the headset
set feels loose
to
with
,
the
bear
bearings,
ings
,
then
off
one-eighth
fIfee eit
contact
back it
one-quarter turn and check it again. You should be able to adjust the
:up by hand, but you can use a suitable tool if you'd like (see photo). If a
.eflector bracket or brake hanger is in your way, move it up the stem, along
with the lockwasher and locknut, while you adjust the cup.
f you feel any binding in the headset, turn the adjustable cup anticlockwise
o loosen it slightly. Start with an eighth- to a quarter-turn, then check it
]gain. After each adjustment of the cone, snug the locknut and recheck
he adjustment.
ow-
Aar
4•11101111110
Continue to work in small increments, adjusting and checking until
you feel neither binding nor looseness in the headset. Be patient and
try to get the adjustment just right. If you cannot find the precise
mint between tightness and looseness, leave the adjustment slightly tight.
)nce you have the adjustment right, secure it by holding the adjustable cup in
msition while tightening the locknut.
210
ILLUSTRATED BICYCLE MAINTENANCE
Threaded Headset Overhaul
1
On most bikes, headsets should be overhauled yearly. This involves
disassembly, cleaning and inspecting, installing new bearings and
repacking with fresh grease.
Put the bike in a repair stand and lay an old sheet under it. If the bearings
are loose and fall, they'll land on the sheet instead of disappearing. Count
them and keep track of their number for replacement purposes.
To take a headset apart, you'll need to remove the handlebar and stem from
the head tube, which is complicated by the brake levers and cables. It may be
necessary in many cases to remove the brake caliper from the fork.
4..
2
Loosen the handlebar stem by turning the expander bolt anti-
3
Set a small block of wood on top of the bolt (see photo), and give it a
clockwise two or three turns.
Don't turn
it too far - you don't want
the threads on the end of the bolt to lose contact with the wedge at
the bottom of the stem.
Dne
sharp blow to dislodge the expander wedge inside the steerer tube.
A wedge that has not been loosened in a while may take more than
blow to free.
.ift the handlebar and stem out of the steerer tube and hang them on the top
ube of the bike. If you prefer, you can disconnect the cable to the rear brake
)nd shifter cables, if you have them, and set the bar aside while you work.
temove the front wheel.
HEADSETS 211
4
Loosen the headset locknut by turning it anticlockwise (see photo). If
it's tight, slide the handle of a hammer between the fork legs and use
it to hold the fork while turning the spanner. Thread it completely off
the steerer tube and set it aside. If there's a second locknut, take it off too.
5
Lift off the lockwasher, the reflector bracket, the brake hanger and
anything else between the locknut and the adjustable cup (see photo).
Remember the order in which each item comes off so you can replace
them in the same way.
You're now ready to remove the adjustable cup. Support the fork with one
hand to hold the lower set of bearings inside the lower head cup until you're
ready to remove them (see photo 6).
11■1111111110-
6
.1111111•1111111F
41•101•111111■Pr
111101
Be cautious as you remove the adjustable cup. Any bearings clinging
to it may drop and roll away. Once the bearings are visible, you may
discover that they are in a metal retainer. If so, you no longer have to
worry about any errant balls getting away from you. However, do not assume
that just because the upper set of bearings are in a retainer the lower set will
be too. Be wary of loose balls until you're sure they are all held in retainers.
If you find that the bearings beneath the adjustable cup are loose, you may
want to momentarily thread the cup back down and lay the bike on its side
on the floor. Then when you take the adjustable cup off, the bearings can fall
out onto the sheet or rags you've spread on the floor.
212
ILLUSTRATED BICYCLE MAINTENANCE
7
8
Remove the bearings from the top head race and save them for
later inspection.
If you can, turn the bike upside down to prevent the bearings from
falling out of the lower head cup while you lift the fork out of the
head tube. Set the fork aside while you extract the bearings (see
photo). Keep the two sets of bearings separate in case they're not identical in
size and number. Clean and count each set, then take a sample to the bike
shop to buy replacements to match.
Clean all the parts and inspect them for pits and cracks in the bearing areas.
Replace any damaged parts. If the fork crown race, the lower head cup or
the top headrace must be removed for replacement, have the work done at
a bike shop, which will have the tools and skills needed.
9
When you're ready to reassemble the headset, lightly grease the
steerer from the fork crown race up to and including the threads at
the upper end (see photo). This will help prevent corrosion and protect
working parts from damage and excessive wear.
HEADSETS 213
1
Pack grease into the lower head cup, the adjustable cup,
and the top headrace. If you wish, fit a rubber shield (see
0 page 203) over the lower cup and fold it back out of the way
until the headset is back together. Install a set of bearings in the lower cup.
11
Place the fork steerer tube back through the head tube, pushing
the fork crown race against the bearings. Install the bearings in
the upper race. Then thread on the adjustable cup and turn it
lown until it makes contact with the bearings (see photo).
)on't fine-tune the adjustment until after the stem is locked back in place.
teplace the reflector bracket, brake hanger, lockwasher, locknut and what.
ver else was taken off. Be sure that everything goes back on in the right
order, but don't tighten down the locknut yet.
Drop the stem into the steerer tube. When it's at the right height
and the bars are straight, turn the expander bolt
clockwise to tighten the expander wedge (see photo). Check the
headset adjustment by performing the various tests described on page 208.
When you have the cup adjusted so you can feel neither binding nor play
between the cup and bearings, hold the cup in place and tighten down the
locknut. Reconnect the brake. Replace the front wheel, and your bicycle
should be ready to ride again.
1
214
ILLUSTRATED BICYCLE MAINTENANCE
Threadless Headset Adjustment
and Overhaul
1
Due to their unique design, it's unlikely that you'll need to adjust a
threadless headset very often. Even if your headset does develop play,
it's a simple matter to adjust.
Feel for headset play by pushing and pulling on the fork with one hand while
holding the down tube of the frame with your other hand. You can also lift
the front end of the bike, drop it and listen for a rattle. Another method is to
apply the front brake and push and pull the bike back and forth, checking for
a knocking sensation that would indicate play in the headset.
To check if the headset is too tight, pick up the front end of the bike and turn
the wheel from side to side very slowly to feel for any binding in the bearing.
It should turn smoothly; if it doesn't, it may be too tight.
To adjust the headset, loosen the stem bolt(s), tighten the adjusting bolt (see
photo) on top of the stem (or loosen it if the adjustment is too tight) and
retighten the stem bolts to lock the adjustment in place. Then recheck the
adjustment and fine-tune it as needed.
2
.m1F
asteansmr
If you can't get a good adjustment or the headset feels crunchy and
full of dirt while turning, overhaul the headset. Place the bike in a
repair stand and disconnect the front brake cable or remove the
brake caliper entirely. Remove the front wheel, which will make it easier to
remove the fork (see photo).
HEADSETS 215
3
Unscrew and remove the top bolt and extract the top cap (place the
parts on a table in order of removal). Loosen the bolt(s) holding the
stem and lift the stem off the fork, while holding the fork with one
hand so that it can't fall out of the frame. Attach the stem to the frame so that
it can't swing and scratch it (see photo).
Slide the headset pieces off the fork and pull the fork out of the frame. Pay
attention to how each piece fits so you'll know how to properly reassemble
them. You're ready to remove the fork.
If you find that the fork is stuck and won't come out, carefully strike it with a
mallet to knock it free (you may have to hit it hard, but be careful).
Clean all the parts and inspect them for pits and cracks in the bearing areas.
Replace any damaged parts. If the fork crown race, the lower head cup or
the upper headrace must be removed for replacement, have the work done
at a bike shop, which will have the special tools needed.
4
1■1111F
41=11
'Mt
When you're ready to reassemble the headset, coat most of the
steerer tube with grease to prevent corrosion, but don't coat the top
section that the stem clamps to. Also pack grease in both cups, coat
the bearings with grease and place them in the cups. Be sure to install them in
the correct direction (see photo).
You can now put the fork back in the frame and install the parts, stem, top
cap and adjusting bolt. Tighten the bolt until the fork turns smoothly without
play. To finish the job, centre the stem and tighten the stem bolt(s) to lock the
adjustment. Reattach the front brake and cable, install the front wheel and
you're ready to roll again.
CHAPTER 13
Brakes
Wheels may be what make a bicycle a bicycle, but without
brakes, many of us might never get to enjoy riding that
bicycle more than once. Early bicycles had no separate
braking system, and riders relied on resisting the motion of
their cranks with leg power to gradually slow down. Modern
track-racing bikes are still made with fixed drivetrains like
those early bikes had. The common thread between the two
is that neither has ever had to deal with busy intersections or
rush-hour traffic on their brakeless cycles.
Thanks to smooth roads and multispeed drivetrains, bicycles move so quickly that they can often outpace city traffic.
With the ability to go fast comes the need to slow down and
stop, sometimes in a hurry. So a reliable set of stoppers has
become of critical importance. Even as we get out of town and
into the country — or into the woods, for that matter — controlling speed with a good set of brakes can mean the difference between making a corner and launching into a ravine.
Major Types of Brakes
Today, there are two major classifications of bicycle brakes:
hub brakes and rim brakes. Hub brakes work through pressure applied at the wheel's hub; rim brakes work by applying
pressure on both sides of the wheel rim.
Included in the general category of hub brakes are three
types: coaster brakes, drum brakes and disc brakes. Coaster
brakes are commonly found on children's bikes, where small
hands and young, undeveloped coordination would make
other types of brakes more hazard than help. Since this type
of brake is quite durable, we will not describe it further. If
yours needs service, have it repaired by a shop mechanic.
Drum brakes are generally found on tandems and bikes
intended for short, urban commutes. For tandems, increased
weight and speed potential are the primary concerns. It's not
unheard of for two skilled tandem riders to reach speeds of
almost 100 kph (60 mph) on long mountain pass descents. With
between 138 and 180 kilograms (300 to 400 pounds) of bike and
riders at these speeds, friction from rim brakes alone could heat
the rims enough to melt the tubes inside.The potential for a horrific crash is obvious. A drum brake applied at the hub can generate tremendous friction to slow the bike down, yet the heat
poses no greater threat than a blister on your finger if you are
unfortunate enough to touch it at the bottom of your descent.
Commuters seek simplicity and reliability. Drum brakes
have both of these in spades. While not as large as those used
on tandems, drum brakes on city bikes have plenty of stopping
power and thick brake pads that can yield years of service for
the average bicycle commuter. What's more, minor wobbles
and dents in the rim that might give a rim brake fits go almost
unnoticed when a hub drum brake is in use.This isn't licence
to let your wheels go to pot, but it is comforting to know that
you could break a spoke on that nasty pothole you hit and still
make it to work on time.
Disc brakes have come a long way from the heavy, inconsistent nightmares ofjust a handful of years ago.Today's bicycle
disc brakes are light and sophisticated, with an impressive
balance of power and modulation (the ability to control and
feel the application of power).
Hub brakes put stress on a wheel more evenly than rim
brakes, which is one mark in their favour. Any hub brake
system requires a specifically designed hub and a frame
equipped to handle the stresses applied to the stays. Thanks to
the advent of a widely accepted standard for fitting brake
rotors and calipers, most mountain bikes today are designed
with disc brakes in mind. Even models already equipped with
rim brakes include specially designed dropouts to which a
disc brake caliper can be installed should the rider wish to
upgrade in the future. Some even have disc-ready hubs to
make the switch that much easier and more cost-effective.
Possible disadvantages of discs may include a rubbing noise
due to disc drag, the special equipment needed for servicing
and the high cost. Drum brakes are just plain heavy and can
lack modulation.
Hydraulic Disc Brakes
If you have hydraulic discs on your bike, get a copy of the
owner's manual for your brakes and rely on it for service
information. Beyond replacing brake pads and aligning the
caliper, it's best to leave service of a hydraulic disc brake to the
experts. Each system, though similar in principle, has subtle
differences in procedure and handling to which you must
strictly adhere. For the adventurous, here are a few tips
common to all hydraulic systems.
The Basics of Hydraulics
There are, no doubt, many millions of pages in print dedicated
to the principles of hydraulics. For the purpose of bicycle
brakes, though, the idea is pretty simple.
The system starts at the brake lever, which actuates a piston
in the master cylinder. When the brake lever is pulled, a
volume of fluid in the master cylinder is pushed out by the
218
ILLUSTRATED BICYCLE MAINTENANCE
nner Workings of a Sic epull Brake
BRAKE CABLE CONNECTION
ADJUSTING BARREL
BRAKE CABLE SEAT
RETURN SPRING
CABLE ANCHOR
CALIPER ARMS
QUICK RELEASE
I
fir
(
/ 'OVA
BRAKES 219
piston and into the brake line. Fluid flowing through the
brake line eventually reaches the caliper, which contains the
slave cylinder(s). The slave cylinders fill with fluid and force
their pistons out, clamping the brake pads onto the brake disc.
This system of hydraulics can achieve pressures of up to 3,000
psi, generating tremendous braking power despite the
diminutive appearance of the caliper and disc.
Care and Feeding
Disc brakes require a minimum of regular maintenance once
they have been set up and adjusted properly. Of course,
nothing is 100% carefree, and your disc brake set is no exception. Beyond the obvious necessity of replacing brake pads
when you've worn a set out, there are a handful of things you
can do to keep those powerful and consistent speed controllers functioning their best.
Keep it clean. Disc brake pads are extremely susceptible to
oil contamination. It's possible for these pads to become permanently ruined as a result of even the tiny amounts of oil
from your own skin. Whenever handling disc brake pads or
rotors, minimize contact of the braking surfaces with your
bare skin. If you do touch the braking surfaces, or if you're
unsure, clean the pads and disc with rubbing alcohol or with
a product approved for cleaning disc brake parts, such as Disc
Doctor or White Lightning Clean Streak. If your brake pads
become soaked with oil, throw them out and replace them.
Once oil has soaked into the pad it cannot be flushed out, and
the heat of braking friction will cause the oil to degrade the
pad material, diminishing braking power and causing it to
wear prematurely.
Keep it dirty. Believe it or not, it's best to not clean your
discs on a regular basis. Oil contamination is one thing, but
everyday dirt and mud will not harm — and they can even
help — braking performance. Tiny particles of dirt embedded
into the surfaces of brake pads and discs increase the amount
of friction the brake can generate. In fact, after cleaning or
changing pads, there is a brief period of diminished braking
power. By riding the bike for a few minutes while dragging
the brakes — called 'bedding' the brakes — particles of the brake
pad material are ground into the disc's surface, thus helping to
restore power.
The Six-Bolt International Standard (right) is the most commonly found
pattern for attaching brake discs. Shimano's new Centre Lock design
(left) allows the use of a steel brake disc mounted on an alloy carrier
to reduce weight and aid in heat dissipation.
of over 260°C (500°F). DOT fluids, however, are extremely
caustic. Great care must be taken to avoid contact with the
skin and painted surfaces.
Dos and Don'ts
Keep in mind that you should use only the fluid recommended by your specific brake's manufacturer. Mineral oils
and DOT fluids are not interchangeable, and serious damage
can be caused by not using the correct fluid. There is no evidence of long-term damage from using different brands of
mineral oil than the brake manufacturer's own blend. Even so,
it's best to stick with Shimano fluid for Shimano brakes,
Magura fluid for Magura brakes, and so on, since that is what
they used in the development of their system. DOT fluids are
a little trickier. Generally speaking, DOT-3 and DOT-4 are
interchangeable. DOT-4 and DOT-5.1 are interchangeable, as
well. But DOT-3 and DOT-5.1 are not. Moreover, it's important never to mix fluids of different types. In some rare cases,
it's best even not to mix fluids of the same designation but
from different manufacturers. Wait, it gets even more confusing. There is also a DOT-5 fluid that should not be confused with DOT-5.1, as DOT-5 is silicone-based and will not
work in any bicycle brake system currently on the market. So,
while DOT fluids are widely available at auto and motorcycle
part stores, your best bet is to get yours from the local bike
shop. They will carry only those fluids approved for bicycle
brake use, so you can be certain they are safe.
Hands off. One of the most common errors in the handling
The fluid controversy. There are two basic types of
hydraulic fluid currently used in bicycle brakes — mineral oil
and automotive-type DOT (Department of Transportation)
brake fluid. Each has a specific benefit and drawback. Mineral
oil is environmentally friendly and easy to work with, but it
is not as heat-resistant as DOT-type fluids and may expand
under prolonged, heavy braking. DOT fluids are engineered
to resist heat expansion and in some cases have boiling points
of disc brakes is also, unfortunately, sometimes the most difficult to correct. Whenever a wheel is removed from the frame
or fork, don't squeeze the brake lever! Doing so on today's
self-adjusting systems can cause the brake pads to clamp
tightly together. Separating pads after this has happened can
require the skill and patience of a surgeon at best, and a complete brake bleed at worst.Aftermarket disc brake sets include
a spacer that can be stuck in the caliper while the wheel is out
220
ILLUSTRATED BICYCLE MAINTENANCE
to prevent this embarrassing and frustrating problem, but
most disc-equipped bikes don't include them. If you don't
have one, fold a piece of cardboard or a few business cards in
half and stuff these between the brake pads.
Read the fine print. Before servicing a hydraulic disc, it's
important to understand the steps, which are similar but
slightly different for each model.
Fortunately, most discs, once set up, require little maintenance. In fact, on a good system, about the only thing needed
is occasional brake pad replacement — usually a simple matter
— and an even less occasional brake-bleed. Because there is no
single method for bleeding we can describe in this book that
could be applied to every hydraulic disc brake, we must defer
to the manufacturers themselves. Before attempting to service
your own hydraulic brake, carefully study that specific brake
system's manual and be sure you have all the tools, supplies
and skills necessary.
Mechanical (Cable-Actuated) Disc Brakes
Though not quite as powerful as their hydraulic cousins,
mechanical disc brakes take the greatest benefit of the disc —
consistency in all weather — and match it with the simplicity
and user-friendliness of rim brakes. A standard brake lever
pulls a cable leading to the caliper, just like a rim brake. The
caliper, rather than a pair of arms, consists of one fixed brake
pad and one that rides on a large screw. The cable pulls on a
lever arm, turning the screw, which pushes the mobile pad
against the disc and, in turn, the disc against the fixed pad.
Though some performance is lost in the force it takes to
deflect the disc before both pads make contact, it's hardly
noticeable from the rider's standpoint. Plenty of riders feel
The basic principles of bleeding hydraulic disc brakes apply to all examples.
Each manufacturer, however, has devised a system that it believes works best
with that particular brake design. If you want to bleed your own brakes, it is
highly recommended that you purchase a factory bleed kit tailored to your
brake set and carefully follow the manufacturer's instructions.
that the benefit of a mechanical system's ease of adjustment
outweighs its very slight lack in power as compared to a
hydraulic system.
Mounting the disc. In the beginning, every disc brake
manufacturer had a unique system for mounting their brake
disc to the hub. Naturally, consumers didn't like the idea that
a certain brand of disc brake would only work with a certain
brand of hub; thus, disc brake sales grew very slowly. When
Hayes decided to enter the scene in the mid-1990s, the first
thing they did was work with other manufacturers to arrive
at a standard for mounting calipers and discs. The Six-Bolt
International Standard (I.S.) was born and disc brake sales
took off. Shimano has recently mixed things up by introducing a spline-mount interface for discs and hubs. It's a good
system that allows for lighter-weight discs and hubs, but it had
a lot of people up in arms for a short time after its introduction. Luckily for us, Shimano's Centre Lock discs come in a
couple of common diameters that allow use of Shimano hub
and disc with another brand of caliper, or vice-versa. There
are also now adapters that allow fitment of a Six-Bolt I.S. disc
to a Centre Lock hub. We're still much better off now than
we were then.
Aligning disc brake calipers. There are a few different sys-
tems used by disc brake manufacturers for aligning the caliper
to the disc. The two most common are the shim-mount
caliper and the floating-mount caliper, the latter of which has
two distinct designs in current use.
Hayes brake calipers incorporate a floating-mount design.
The Hayes caliper is mounted to the frame or fork using an
adapter. On this adapter, the caliper has a small amount of free
side-to-side movement before it is tightened in place, centred
over the disc. The only two exceptions are Manitou forks,
which are designed to allow Hayes calipers to be directly
mounted, and mountain bike frames from the late 1990s that
used a Hayes-specific mount on the left chainstay. In either of
those cases, the procedures described here still apply, though
the adapter is not present.
To begin, it's important to be sure that the two bolts holding
the adapter to the frame's or fork's mounting tabs are tight. Use
a 5 mm hex key to loosen the two bolts holding the caliper to
the adapter.About one full turn should allow the caliper to freely
float side to side on the adapter, yet have a minimum of free upand-down movement. If the caliper wants to pull to one side,
remove any guides or zip-ties holding the hydraulic line to the
frame so the line doesn't tug at the caliper.
Wrap an elastic band over the handlebar and brake lever to
clamp the caliper to the rotor while keeping both your hands
free to work with the caliper. Assuming that both pistons of
the caliper are moving an equal distance, the caliper should
centre itself on the disc.
BRAKES 221
6-inch rotor
8-inch rotor
Forces generated by disc brakes can be so great that brakes with rotors
with a diameter greater than 6 inches (such as the 8-inch rotor on the right)
should be used only on forks approved by the manufacturer for larger rotors.
As with Hayes' floating mount, the bolts holding the
caliper to the adapter should be tightened little by little. Turn
one bolt about one-eighth turn, then the other, and repeat
until both are tight.
Remove the elastic band that holds the brake lever and
check the caliper alignment. Hold a sheet of white paper on
the other side of the caliper as you look through from behind.
Daylight should be visible between both pads and the disc. If
one pad is touching or if the disc scrapes as the wheel spins,
slightly loosen the bolts holding the caliper to the adapter and
move the caliper by hand to fine-adjust the pad clearance.
Avid disc brake calipers also have a floating-type mount,
but with a series of hemispherical washers that allow the
caliper to be aligned in all directions, compensating for
inconsistencies in a frame's or a fork's brake mounting tabs.
Calipers from Avid come out of the box with adapters
already mounted. Don't disassemble these until you've taken
note of the exact sequence of all of the washers — the sequence
of the washers is critical to the function of Avid's Tri-Align
system. Mount the caliper and adapter into place on the frame
or fork using the supplied bolts. If you're readjusting an
existing system, remove the brake cable from the caliper.
Loosen the bolts holding the caliper to the adapter about
one full turn. With this done, the caliper should slide and
rotate smoothly on the hemispherical washers. The red dials
on either side of the caliper adjust the position of the brake
pads. Turning these clockwise moves the pads closer to the
disc; anticlockwise retracts the pads back into the caliper.
Using these dials, clamp the disc with the pads roughly in the
centre of the caliper body.
Snug the bolts holding the caliper to the adapter little by
little.The best technique is to turn one bolt about one-eighth
turn, then the other, and repeat until the caliper is tight.
This will help prevent the caliper 'walking' side to side from
friction with the bolt.
Back the outside pad out as far as it will go by turning the
outside dial adjuster anticlockwise. Turn the inside dial
adjuster just a few clicks anticlockwise. Push the caliper's lever
arm by hand to ensure that the pad is fully retracted, and give
the wheel a spin. If there is any rubbing, turn the inside
adjuster one click anticlockwise and repeat until there is no
more contact. Ideally, there will be a gap of less than 0.5 mm
between the fixed pad and the disc with no scraping.
Adjust the position of the outside pad by turning the outside dial adjuster clockwise. Do this a few clicks at a time and
then push the lever arm up. When it stops about halfway
through its travel to the cable stop, the adjustment is correct.
Now you're ready to anchor the cable. Run the cable from
the lever to the caliper. Using your fourth hand tool, pull the
free end of the cable through the anchor and set the lever arm
about one-quarter of the way through its travel and give the
lever a few good, strong squeezes to make sure everything is
settled into place. It's best to make fine adjustments to lever
feel at the cable anchor, rather than using the adjusting barrel
on the lever. The barrel adjuster is there primarily to quickly
adjust for pad wear while out on the road or trail.
To finish, trim the free end of the cable no more than 20
mm (X inch) from the anchor bolt to prevent it getting caught
in the disc. Crimp the cable end and you're all square.
Magura, Hope and Shimano disc brakes, among others, use
shims between the caliper and mounting tabs on the frame or
fork. Shims are essentially just thin washers made
in specific thicknesses. On these brake systems, the shims are
used in stacks between the caliper and frame or fork to position the caliper perfectly over the brake disc. The process
is relatively easy but requires a steady hand and a little bit
of technique to perform quickly. On the up side, shimming
usually has to be done only once.
Start by setting the caliper in place by turning the bolts in
just a few threads so the caliper can float from side to side.The
hydraulic line will try to pull the caliper to one side or the
other, making precise adjustment more difficult. Remove any
clips or zip ties holding the line to the frame or fork to minimize this tendency.
Wrap an elastic band over the handlebar and brake lever to
apply constant pressure to the brake pads. Both pistons of the
caliper should move an equal distance and the caliper will
clamp itself, centred on the disc.
Determining the correct number of shims for each
mounting bolt is a simple process of trial and error. The correct number of shims is as many will fit snugly between the
mounting tabs of the frame/fork and caliper. It's possible —
even likely — that each mounting bolt will require a different
number of shims. Magura and Hope shims are circular
washers that require the removal and reinstallation of the
mounting bolts to be put in place, while Shimano shims are
Y-shaped and can be installed and removed easily using a pair
of needlenose pliers. Tighten the mounting bolts and you're
ready to check your work.
222
ILLUSTRATED BICYCLE MAINTENANCE
Check the brake pad clearance in the caliper by first
removing the elastic band squeezing the brake lever. Ideally,
there will be small gaps between both brake pads and the disc
through which you can see daylight.To make this easier to see,
hold a sheet of white paper on the other side of the caliper.
Rim Brakes
There are two types of rim brakes in common use today:
sidepulls and cantilevers. A third type, the centrepull, can be
found on road bikes dating back to the 1960s and 1970s and
on mountain bikes from the 1980s.
Sidepulls were popular in the early and mid-1950s mainly
because that was all that was available. Then in the late 1950s
and early 1960s, quality centrepull brakes were introduced by
Universal, Mafac and Weinmann, and they quickly gained
favour. Though seldom found on new bikes sold today, centrepull brakes are still available. One of their attractions is that
after the initial installation and adjustment are complete, these
brakes are basically self-centring, whereas early sidepull brakes
were always dragging one shoe on the rim (a problem that's
been solved on modern designs).
A second attractive feature of centrepull brakes that popularized them when they came out is the greater mechanical
advantage they offered over most sidepulls made at the time.
This was because the pivot points for centrepull caliper arms
are closer to the rim. Sidepulls pivot on a single mounting
bolt, which is directly above the tyre. Centrepulls, by contrast,
are provided with a pivot on each side of the brake body,
decreasing the distance from the pivot to the brake shoe and
thus increasing the mechanical power of the brake.
When it first occurred, this design innovation made possible the use of levers that were smaller and had shallower
contours than those previously required for sidepull brakes.
This was a distinct advantage for cyclists with small hands,
such as younger children and smaller-framed women.
Despite the mechanical advantage of centrepull brakes, by
the mid-1970s the trend had reversed and the sidepull was
again becoming the brake most favoured by riders. Starting
with the Campagnolo Record model, greatly improved and
refined sidepulls began to appear on the market. Many of the
attractive features of the popular centrepull systems were now
incorporated into the newer sidepulls. Quick-releases, cable
adjusters and better finishes were the order of the day. Now
there are even dual-pivot sidepull brakes that rely on pivots
closer to the brake pads, which creates more braking power
and easier brake centring. In fact, the design is so good, it's
doubtful that centrepulls will ever become popular again.
A cantilever brake works much like a centrepull brake but
has shorter, stiffer arms that bolt to pivots built into the fork
and stays. Because the posts are very close to the rim and each
short arm has its own mount, cantilevers have a great
mechanical advantage. This is why they're commonly used on
tandems and loaded tourers, which carry much greater loads
than ordinary lightweight bikes. Cantilevers are also the
brakes on many mountain bikes because fat tyres create reach
problems for ordinary caliper brakes.
As off-road riders ventured further into the woods and
tested their skills on dangerous descents, two new mountain
bike brake designs evolved in the late 1980s: the U-brake and
the rollercam. Both have more power than conventional cantilevers and were standard equipment on many mountain
bikes for several years. U-brakes are heavy-duty centrepulls
with arms that attach to the frame like cantilevers. Rollercams
use a cam-and-pulley system to amplify pressure on the rims.
One advantage of both types is that they do not protrude
from the side of the frame like cantilevers. Consequently, they
provide more heel clearance on small frames and are less likely
to cut you in a crash. These brakes are quite rare today —
unfortunately, they proved difficult to adjust and maintain, so
they went out of favour fairly quickly, while cantilevers were
continuously refined.
The refinement of the cantilever brake eventually led to
the direct-pull cantilever — sometimes called the V-brake
because of Shimano's popular V-Brake model. Direct-pull
cantilevers are awesome grippers, great for mountain bikes,
tandems and tourers. Interestingly, they share the best designs
of cantilever and sidepull brakes. The arms mount to posts
attached to the fork and stays, but the cable runs directly to
the brake arm instead of to a hanger as on regular cantilevers.
This makes the cable action much more efficient and greatly
simplifies adjustment. Two other things make the direct-pull
an outstanding stopper. The brake pads are mounted in the
stiffest possible location so all the force reaches the rim, and
the brake arms are quite long, increasing the leverage applied
at the rim. Direct-pulls are great new brakes, and they have
quickly become a must-have item for mountain bikers who
push the limits of speed and control.
Brake Cable Housings
These days, nearly all brake manufacturers have switched over
to flat-wound cable housing, first used by Campagnolo. The
flat-wound housing gives a more solid feel because, when the
faces of the coil wires lie flat against each other rather than
being round as in the older housings, there's less compression
and slippage between the coils.
Cable housings lined with nylon, now a common practice,
also help produce a brake system that gives a more responsive
feel.A further improvement is the practice of coating the cables
with Teflon. When these various innovations are combined into
one system, most of the friction formerly incurred in the cable
portion of a brake system is reduced or eliminated.
There are even supercable systems today such as Avid Flak
Jacket cable sets and others.These sets include the inner wires,
housing sections and ferrules (the caps for the ends of the
BRAKES 223
housing sections). What's unique about these supercables is
that, when assembled, the cables are sealed so no dirt can get
in to contaminate things, and they're designed with slippery
materials so that the cables move with hardly any friction.
Such efficiency comes at a price, these supercables are much
more expensive than ordinary cables and housings. However,
if you need to improve braking or shifting and minimize your
cable maintenance, or if you're looking for a way to get the
cables working smoothly on a bike with an unusually twisty
cable path, these supercables are a great upgrade.
Installing Brake Levers
There are two types of road brake levers — conventional and
aero — commonly used on drop handlebars, and they are
installed differently. With aero levers, which are common
today, the cable housing starts inside the lever and runs under
the bar tape.This streamlines the front of the bike, protects the
cable and housing better than conventional levers, and offers
a more comfortable hand position. It also makes it possible to
work on your bike upside down because there are no cables
in the way. Conventional levers are still found on many older
road and touring bikes and are distinguished from aero levers
Buying the Right Brakes
by cables and housing that exit from the top. Today, they are
commonly referred to as non-aero levers, since
Before purchasing new brakes, make sure they'll
aero-type levers are now the norm.
fit your bike. For sidepulls, first determine
The first step when installing a new
the dimension from the brake
set of brakes with non-aero levers is
mounting hole to the centre of the
to fasten the levers to the bar of
rim. Measure the distance with a
your bike. However, we recomcaliper. There are two general
mend mounting aero levers to
`sizes' in which most brakes
the bar after installing the
are available — short-reach 47
cable and housing because
mm and long-reach 52
the brake spring tension
mm. Both have a range of
BRAKE MOUNTING
will ensure that the
adjustment of approxiHOLE
CENTRE OF RIM
housing is properly seated
mately 5 to 10 mm in
in the lever.
each direction. There are
Many brake sets come
other sizes on the
with rubber hood covers
market, but these two
CENTRE OF RIM
that fit around the lever
make up 90 percent of
covers
bodies. These
those used on lightweight
increase the comfort of
bikes. Make sure that the
riding with the hands
brakes you want will fit
resting on the lever hoods.
your frame.You can always
If you are reusing a set of
take your bike to the shop
levers that lack these covers
for a trial fit.
or if you need new ones,
For cantilever and
Before buying a new set of brakes, make sure the calipers (the arms
consider buying a pair. Fit
direct-pull cantilevers, it's a
to which the brake pads are attached, above) can be adjusted to fit
them over the levers before
little simpler. They'll fit on
the distance between the brake-mounting hole (represented here by
sliding the levers on the hanalmost any bike with brazethe top centre of the brake) on the frame or fork and the centre of
dlebar. Spray a little alcohol
on brake posts, such as most
the rim (where the vertical line above intersects the rim cross-section).
inside the new hoods to ease
mountain bikes, hybrids,
installation. You will find that
many touring bikes and
tandems. Today, there's a standard position for these braze-on they'll slide into place with less effort and shouldn't slip once
brake posts, and almost all cantilever brakes and direct-pull the alcohol has evaporated.
Of course, before you can attach new levers, you must
cantilevers will fit well.
The exception is if you happen to have an older bike that remove the old ones, and that means stripping off your
is equipped with a U-brake or rollercam. These use posts that handlebar tape. Old bar tape is seldom reusable, so buy new
are mounted in a different location. With these, it's probably tape to go along with your new brake system. Even if you are
not installing new levers but only repositioning the old ones,
best to stick with the brakes you have. If you must replace
them, it's possible to have a frame builder remove the old you may need to remove the old tape before the lever clamp
posts and braze on ones that will accept modern cantilevers can be moved. (If the levers are being moved a tiny amount,
or direct-pulls. It shouldn't cost too much, but the brazing you can sometimes just wiggle them into place without
will damage the paint and you'll need to respray the frame.
removing the tape.)
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Use a third-hand tool to hold brake pads against the rim while
bit and add a little more alcohol until the grip slides off the
bar. Loosen the lever clamping bolt with a hex key and slide
the lever off the handlebar.
When installing new levers, consider the order of assembly
of the shift levers first. Sometimes the shifter goes on first
(thumb levers), sometimes the brake lever does (twist grips).
Before tightening the lever, place it so that its end does not
protrude past the end of the bar. If you crash, this will help
save the lever from damage.
Even more important, adjust the lever so that it's in line
with the natural bend in your wrist when you sit on the seat
and rest your hands on the grips.You don't want to squeeze
the brake lever with bent wrists. When the lever is positioned
correctly for you, tighten the clamping bolt. Then install the
shifters, if necessary, and the grips. Lubricate them with
alcohol if needed. They'll be slippery at first, but the alcohol
will evaporate quickly and the grips will stick.
the cable is being tightened.
Installing Brakes
Once the tape is out of the way, loosen the brake cable
anchor nut and pull the cable free from the brake caliper.
Unhook the fitting on the upper end of the cable from the
lever and remove both the cable and the cable housing from
the bike. Squeeze the lever in so that it touches the handlebar.
Look inside the lever body and you'll see a clamp bolt or nut
that's holding the lever to the bar. Find the tool you need to
loosen that nut. It will probably be either a flat-head screwdriver, a thin-wall 8 mm socket or a hex key. Loosen the nut,
then slide the lever off the handlebar. On Shimano STI and
Campagnolo Ergopower brake levers, the clamping screw is
on the side of the lever body and is loosened with a hex key.
The positioning of brake levers varies with the personal
riding style of each rider, but a standard used by many veteran
riders is to position the lower end of the lever even with the
extension of the lower part of the handlebar. Move them up
or down a bit to suit your taste.
If you are installing non-aero levers, find the tool that fits
the nut on the clamp bolt and fasten the levers to your bar.
Take care in doing this: some models of levers have mounting
bolts that bear on the lever pivot pin. If you have this type of
lever and you overtighten the bolt, it may cause some binding
in the lever movement. In this case, tighten the mounting bolt
just enough to keep the lever assembly from twisting on the
handlebar when you tug on it.
Mountain levers. Removing and installing mountain bike
brake levers means dealing with the handlebar grips. If you're
replacing a worn pair, simply cut off the old ones with a
utility knife. Be careful — it's easy to slip when cutting against
the round handlebar beneath.
If you want to save the old grips, slide a small screwdriver
beneath an edge and drip in a little alcohol. Twist the grip a
To remove an old pair of sidepull brake calipers, loosen the
nut on the tail end of the mounting bolt and take the calipers
off the bike. To install a new set of calipers, first differentiate
the front calipers from the rear by comparing the length of
their respective mounting bolts. The caliper with the longer
bolt goes on the front, and the one with the shorter bolt goes
on the rear. Once you've determined which is which, insert
the mounting bolt through the mounting hole in the frame,
thread on the mounting nut and snug it down. Don't worry
about getting it really tight until later, after you have centred
the calipers on the wheel.
Cantilever and direct-pull brakes are attached to the frame
with two hex bolts that screw into the frame posts. Once the
cable is detached, removing the brakes only requires removing
the hex bolts and wiggling the brakes off the posts. It's important, though, to keep track of the small parts that are inside
each brake arm, so take off one side at a time. That way, if you
drop something, you can always refer to the other side to see
how the parts should fit together. If you tie or tape the brake
arm parts together during removal, they'll stay put.
When installing cantilever or direct-pull cantis, grease the
outside of the brake post and slide the brake arm in place, first
making sure that any springs or washers are in the right place
and seated. Then install the hex bolt (there's usually a washer
that goes beneath it), screwing it fully into the post. Sometimes new brakes come with a drop of factory-applied thread
adhesive on the brake bolts. If yours did not, apply a drop
now, before installation. It'll help the bolt stay put. Be very
careful not to overtighten this bolt — it needs to be just snug.
If you overtighten it, you can damage the brake post, bulging
it and binding the brake.
When the brake is in place on the frame, adjust the brake
shoes. The pads should strike the rim squarely. Too high and
BRAKES 225
they may rub the tyre; too low and they may dive beneath the
rim. If the shoes are on a post, ensure that it's adjusted evenly
on both sides.
Cables and Cable Housing
The next step is to install the cables. Many cyclists try to
reduce friction in their cables by making the cable runs as
short as possible, often trimming several inches off the
housing that comes with their bikes. While there is certainly
no need for enormous cable loops over or in front of your
handlebar, don't go overboard in the other direction, either.
Unnecessarily long cables are a source of excessive friction,
but so are cable runs that are too short — they produce bends
that bind the cable in the housing and may even prevent you
from turning the bar far enough to the side. When you install
new cables and housing, cut away the excess, but leave sufficient length for loops that are large enough to prevent any
kinking in the housing or joints when the handlebar is turned
sharply to one side or the other. Kinks will cause premature
wear and fraying of your cables.
On mountain bikes, copy the old housing path. Usually,
the only tricky section is where the rear brake cable exits the
lever. It can pass on either side of the stem.Try it on both sides
and use the position that provides the least resistance when
the bar is turned from side to side. Usually, this means that the
housing will run from the brake lever, around the left side of
the stem and onto the housing stop on the top tube.
If you're working with aero levers, size your housing carefully before cutting it. The rear housing passes in front of the
head tube and through the top tube cable guides to the back
brake. Be sure to make it long enough so that the handlebars
turn freely Both the front and rear brake housings should be
long enough to follow the shape of the handlebar, run
beneath the tape and exit near the stem. Before cutting, grease
the brake cables, install them in the aero levers and thread
them through the housing and into the anchor bolts on the
calipers. Pull each cable end so that the housing seats inside
each lever. Then, while pulling on the cable, squeeze the
Cut cable housing using a sharp pair of cableor diagonal-cutters.
caliper and tighten the anchor bolt. It helps to use a thirdhand tool (a special tool that hooks over both brake shoes and
presses them towards each other) or a toe strap to hold the
caliper together.
Fasten the aero lever to the handlebar so that the lower end
of the lever is even with the extension of the lower part of the
bar. Tape the housing to the handlebar in two places on each
side. Check that there is enough housing to allow the bar to
turn freely without binding the cable.
Sizing Cable Housing
Once you've laid out the cable runs and determined the
Lengths, trim the housing.The tools that are needed to cut the
housing cleanly are a pair of purpose-built cable cutters like
the Park Tools CN-10 cable cutter or a sharp pair of diagonal
:utters, a small file and an awl or similar pointed tool.
With aero levers, because you've already installed the
cables, you must first pull the cable out of the housing a little.
Do this by loosening the cable anchor bolt and squeezing the
brake lever. When the lever is open, reach inside and pull out
the head of the cable with needlenose pliers.You will cut the
housing near the caliper, so don't pull the cable out very far.
Cut the housing at the proper length with the cutters.
Look closely at the end of the housing to see if a burr has
D een created.You want a clean cut. If there's a burr, cut the
end again or file the end square. Usually, it's also necessary to
reopen the liner inside the housing. That's what the awl is for.
Work it into the liner to round it out.
If you're installing a new set of brakes, the cable housing
:nay have small metal ferrules mounted on each end or supalied loose in the package. If they're loose, save them to put
n the ends of your housing after you cut it to length. These
terrules provide protection for the ends of the housing and
lelp support the housing where it seats in the lever and the
:alipers. If you leave them off, the cable will have a tendency
:o cock to one side and not line up with the lever housing or
:aliper housing stop, giving a spongy feel, and wearing the
:able prematurely. Some brakes do not use ferrules, though.
If a burr forms at the end, snip it away.
File the end of the housing flat so it doesn't try
to bite-in under pressure and bind the cable.
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If you're trying to install ferrules to a brakeset but they just
won't fit, the brake probably wasn't designed for them.
Attaching Cables to Brakes
If you are working with road aero levers, reattach the cables to
the calipers.To do this, push the cable back into the lever until
it comes out of the housing, then pull on the cable end until
the head of the cable seats in the lever. Thread the cable into
the anchor, squeeze the caliper and fasten the anchor bolt.
With non-aero levers, before running the cable through
the housing, grease the cable and install the housing ferrules
(if your brakes came with them). Thread the cable through
the hole in the upper part of the brake lever. Catch the head
of the cable in the anchor provided for it inside the lever,
making certain the anchor is turned so that the cable head
will properly seat itself when the cable is pulled taut.
On mountain bike levers, you usually must rotate the
adjusting barrel to line the slots up so the cable can be fit into
place. With the cable and housing in place, turn the adjuster
back to its starting position seated against the lever (fully
clockwise).
Once the cable has been routed through the housing,
fasten it to the calipers and trim away any excess. For this, you
need some means of holding the calipers against the wheel
rim while tightening the cable. There is a tool called the third
hand that is made for this purpose. It hooks over both brake
shoes and presses them towards each other. If you don't want
to invest in this handy tool, ask a friend to help you or create
your own third hand by using a shoestring or a toe strap from
your bicycle. Still another approach is to slightly tighten the
anchor nut on the cable, then hold the calipers together with
one hand while pulling the cable taut, then tighten the
anchor nut with the other hand. Experiment to find the
method that works best for you.
Before tightening the cable, check to make sure the brake
quick-release (the lever or button on road brakes that is used
for opening the brake for wheel removal) is shut. Screw the
cable adjusting barrel all the way down, then back it off a
couple of turns. Check to make sure that the cable end is
seated properly in the brake lever and the housing ends are
seated in the frame stops. If all is in order, pull the cable taut
and tighten the anchor nut.
Release the calipers and squeeze the brake lever several
times to stretch the cable. If the cable seats and stretches so
much that the lever hits the handlebar when you squeeze it
hard, squeeze the brake pads against the rim again and pull the
cable tighter. Anchor the cable at a point that will provide
3mm of clearance between each brake shoe and the rim before
you squeeze the lever, and 2 cm of space between the lever and
the bars when you squeeze it hard. (You may opt for a different
setting later, but this is a good starting point.) Once you have
the cable in that position, tighten the anchor bolt enough to
prevent any cable slippage when braking hard. Leave 2 to 4 cm
of cable protruding from the anchor bolt and use sharp cable
cutters to trim away the rest.
Once you have trimmed the end of the cable, you need to
do something to prevent it from fraying. The sharp strands of
a frayed bike cable are not kind to human hands. One way to
prevent cable fraying is to use premanufactured end protectors. They're available in aluminium or plastic. The aluminium
type are slipped over the cable end and then crimped with
your cutters. The plastic ones are installed similarly, except
that they don't have to be crimped. They're easier to install,
but less permanent.
If you don't have one of the little end caps, you can solder
the cable end. To do this, a soldering gun (a cigarette lighter
will work, too), solder and flux are needed. Use alcohol to
wipe off any dirt and lubricant from the end of the cable. Stick
the portion of the cable that is to be soldered into the flux.
Apply the hot tip of the soldering gun to the cable, and the
heated flux will begin to smoke and sizzle as the heat rises.Test
the cable with the solder, and as soon as the solder starts to
melt, work it up and down the cable end. While the solder is
still fluid, wipe it with a damp rag to give it a clean finish.
A word of caution: solder just the tip of the cable. Don't
solder anywhere near where the anchor nut holds the cable.
Soldering makes the cable very stiff, and the cable must be
flexible for the brake to work properly. Also, depending on the
nature of your anchor, stiffening the anchor point itself may
encourage the anchor to cut through the cable.
Centrepull and Cantilever Brakes
Centrepull and cantilever brakes resemble sidepulls in some
ways. The method of attaching levers to handlebars is the
same, but the way brake cables are connected to the calipers
is different. The main cable on a centrepull or cantilever
attaches to a metal yoke or `pick-up', which in turn is
attached to a short transverse cable, also known as a linking,
stirrup, crossover or straddle cable. The ends of the stirrup
:able are attached to the caliper arms. When you squeeze the
Lever, the main cable lifts the stirrup cable, which then pulls
the caliper arms and brake pads against the rim.
The body of a centrepull brake is fastened to the bike
Frame like a sidepull is: a mounting bolt and nut lock it to the
Frame. Cantilevers, by contrast, do not have a single body.
Instead, each side of the brake is independently attached to
:he frame. Each half of a cantilever brake is bolted to a braze:) n boss that is equipped with a steel spring that pushes the
c rake shoe away from the rim after the lever is released.
On a centrepull brake, you'll find a cable stop mounted on
a hanger that is suspended above the calipers, usually on the
:op of the headset or the seat tube, depending on whether it
.s the front or rear brake. Some hangers are integrated into the
;tem or are brazed to the seatstays.
BRAKES 227
For all types of brakes, if the hanger has a quick-release, be
sure it is closed before adjusting the cable length. The stirrup
cable pick-up will have an anchor with a hole in it. Thread
the cable through the bolt. Once the brake cable is threaded
through the bolt and the stirrup cable is in place in the
channel provided for it on the yoke or pick-up, pull the cable
taut and tighten the nut on the cable anchor bolt.
Hold the brake pads against the wheel rim with a thirdhand tool or some other means while finishing this cable
attachment. As with sidepull brakes, adjust the cable length so
that there is 3 mm of clearance between each brake shoe and
the rim when the levers are released. After you initially
tighten the anchor bolt on the cable, squeeze the levers
several times to stretch the cable and seat the housing. If
necessary, take up the slack at the anchor. Once you've
accommodated the initial cable stretch and re-anchored the
cable, trim away the excess cable. Leave only an inch or two
sticking through so the loose end of the cable will not foul up
the operation of the calipers. Protect the cut cable end from
fraying by installing a cable cap or by coating it with solder,
as described earlier.
Direct-Pull Cantilevers
The first factor in setting up direct-pull cantilever brakes is
making sure that you have the right parts. Direct-pulls won't
work with just any brake lever. If you combine a direct-pull
canti with a brake lever that is designed for conventional
brakes, you won't get proper performance. Usually, it's best to
purchase the brakes and levers as a set. In some instances,
however, this may not be possible. One example is using
direct-pulls on a tandem with drop handlebar brake levers.
These levers are certainly not designed to be used with
direct-pulls. Fortunately, there's a good solution now because
a few companies offer adapters that fit on the cable or lever
and adapt the pull of the lever to work with direct-pulls.
Once you're sure that the levers are compatible, direct-pull
canti adjustment is pretty easy. The arms should be close to
parallel in the final setup. To achieve this with different rim
widths, each brake pad usually has a thick and thin washer.
Place the appropriate washers for your rims between the pads
and arms (keep one inside and one outside).Tighten the pads
so that they strike the rim squarely and flat (it's not necessary
to toe-in pads on direct-pull brakes). One way to make pad
adjustment easy is to release the spring on the side that you're
working on. This will hold the pad against the rim, making it
easy to find the best position and tighten the pad. Then adjust
the cable at the anchor bolt until the arms are close to parallel, which should provide good clearance and brake function. If you squeeze and release the lever and one side of the
brake remains closer to the rim, centre the brake by turning
the centring Phillips screws on either side. Tightening pulls
the pads away, and loosening pushes them closer.
It's possible to set the pads slightly wide on direct-pulls
because the stopping power is so great. Because you have more
mechanical advantage in your hands as the levers get closer to
the bar, experiment with this setting. It's a favourite of racers
who also want to ensure that the pads don't rub the rims.
Brake Centring
Before beginning the brake-centring process, spin the wheel
to see if it's true, that it's centred and that it's fully inserted in
the frame/fork. If it's not, true the wheel or centre it before
proceeding. Otherwise, either the wheel will end up dragging
on the brake pads, or the adjustment will have to be on the
loose side and may result in a pulsating or jerky braking
action. If you have as much as 5 mm of clearance between
either brake pad and the rim at any point during the revolution of the wheel, and contact between rim and pad at any
other point, your wheel definitely needs truing.
Once the wheel is running true, it's time to check the distance of the brake pads from the rim.The clearance should be
equal on both sides. To check whether sidepull calipers are
centred, loosen the rear mounting nut just enough to allow
the calipers to move from side to side, but not so much that
the calipers become floppy. Squeeze the brake lever to bring
the shoes into firm contact with the rim. Keeping the pressure on, snug up the mounting nut enough to keep the
calipers from pivoting on the fork crown or brake bridge.
Release the lever and check to see if the calipers are, in
fact, centred. If the arms don't contact the rim evenly or one
brake shoe leans against the rim after you release the brake
lever, you'll have to align the calipers. How this is done
depends on the type of brakes.
There are several ways to centre a sidepull. First, try
loosening the mounting bolt, twisting the caliper and retightening the mounting nut. That should do it for Shimano
and Campagnolo dual-pivot designs. If they need a little finetuning to get the centring perfect, there are centring hex
screws for this purpose on the top of the Shimano brake and
on the sides of the Campagnolo. These should be used for
minor adjustments only; make major ones by repositioning
the caliper as we described.
Lesser-quality sidepulls don't have centring screws. If yours
is off-centre and repositioning it doesn't do the trick, try
using the two nuts that hold the caliper arms on the front of
the brake. First, lock the two nuts tightly together by turning
the inner one anticlockwise and the outer one clockwise.
Move one spanner to the rear mounting nut, leaving the
other at the front. Twist both spanners in the same direction
to rotate the brake body.
If you need to rotate the brake body in a clockwise direction to centre the calipers, keep your spanner on the outer of
the two front nuts. If you need to rotate the brake body anticlockwise, keep your spanner on the inner of the two. This
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ILLUSTRATED BICYCLE MAINTENANCE
way you will not loosen these nuts in relation to each other
while making the adjustment.
Some sidepull brakes have a nut with centring flats located
behind the calipers, between the calipers and the frame.
Placing a cone spanner on this nut allows you to turn the brake
to the right or the left and hold it there until you have tightened the nut on the end of the mounting bolt. Once it's tight,
hold the spanners on these two nuts and turn them together to
rock the brake body into the desired position.
Centring a centrepull brake is similar, though simpler, than
centring a sidepull because there is only one place to put your
spanner. Loosen the nut that is found on the tail end of the
mounting bolt, twist the body of the calipers (the part the
caliper arms attach to) until it is centred, then hold it there
while you retighten the nut. (In a pinch, gently tap on one
side of the brake with a mallet to centre the brake.)
The pads on a cantilever brake should be set equidistant
from the rim to ensure an even braking action. If the arms do
not move against the rim at the same rate, slide the cable
pick-up along the stirrup towards the brake pad that is slowest
to reach the rim. Squeeze and release the brake lever a few
times to check whether the pads stay centred. If not, disconnect the stirrup cable from one side of the brake, and add
spring tension to the arm that's sticking. To do this, rotate the
brake away from the rim. The brake will rotate freely up to a
point and then resist. Turn the brake another quarter-turn
past this point. This unwinds the spring and increases spring
tension. You may have to rotate the brake against the spring
several times to add enough tension.
Many brakes have provisions for unequal spring tension.
Look for multiple spring holes on the frame posts. If there are
several holes, you can adjust spring tension by removing the
brake and moving the spring tab to another hole.
Another nifty feature found on direct-pulls and cantilevers
is tension-setting screws (centring screws). Some brakes have
screws on both sides, while others use them on only one side.
Turning a screw clockwise increases spring tension and moves
the shoe away from the rim. Turning it anticlockwise reduces
tension and effectively moves the other pad away from the
rim.
One last point about brake centring: a sticking brake pad
can make you think the brake is not centred, when the brake
pad is actually the culprit. When the brake pad is positioned
wrong, it wears unevenly The part of the pad that strikes the
rim wears down, but a thin lip develops at the edge of the pad
that is not hitting the rim. When this lip catches on the rim
when the brake is applied, it causes one side of the brake to
stick.To fix this problem, cut off the lip with a sharp knife and
sand the pad so it's the same depth throughout. Readjust the
pad so it strikes the rim properly.
Once your brakes are centred, check the cable slack a final
time. If the brake pads are within 3 mm of the rim, leave the
initial adjustment. If not, loosen the cable, take up more of the
slack, then reanchor the cable. Use the cable adjusting barrel
to fine-tune the brake so that the pads end up being between
2 and 3 mm from the wheel rim.
As you use the brakes, you will discover some gradual
stretching of the cable. Take this up with the adjusting barrel.
If the stretch becomes so great that you use up all the finetuning that is available through the cable adjusting barrel,
si mply screw the barrel down as you did when you installed
the cable, hold the calipers against the rim and take up the
slack at the cable anchor.
Solutions to Common Problems
A common problem with new brake installations or newly
installed brake pads is the nerve-wracking squeal caused by
pad misalignment. If brake pads hit rims perfectly flat or with
the rearmost edge first, they can vibrate and squeal. There are
several ways to fix this, and most involve changing the way
the brake pads meet the rim. With the exception of directpull cantilever brakes, brakes should be adjusted so that the
leading (front) edge of the brake pad hits slightly before the
trailing edge. This adjustment is called toe-in.
On sidepull brakes, the pads either include a holder that
allows for angling the pads, or the pads are toed-in by gently
bending the brake arms.To do this, remove the brake shoes and
use two adjustable spanners simultaneously. Put one on the flat
surface of each arm and gently bend. When you reattach the
brake shoes, you'll notice that they are now positioned differently. The gap shouldn't be too large at the rear of the brake
shoe — 2 mm is about right. If you bent the arms too far,
remove the shoes and reverse the toe-in procedure.
Most cantilevers have special spacers on the pad holder
that allow you to make pad angle adjustments.You can toe-in
the pads by loosening their mounting nuts and moving the
pad or shaped spacers by hand.When the pad is in the correct
position, tighten the nut.
If you reposition the brake pads and your bike still squeals,
try sanding the rims with medium emery cloth. They can
develop a glaze that creates excess friction when the brake
pads hit them.
Hardened brake pads can also cause squealing. This occurs
with age. Try scratching the rubber with your fingernail. It
should be resilient, not hard. If it doesn't give, replace the pads.
One common problem on mountain bikes today is directpull brakes that squeal no matter what you do. If you run into
this, try installing a brake booster. This aluminium or carbon
horseshoe-shaped device attaches to the bolts that hold the
direct-pull brakes on the frame. The booster acts as a brace,
tying together the sides of the frame, and preventing the flex
and vibration that causes the squealing.
The booster also adds braking power because it prevents
the seat stays from flexing outward when the brake is applied.
BRAKES 229
Although it may be unsightly, you'll probably grow to appreciate having it.
Cables also may suffer the ravages of the elements. Covered cables and those coated with a protective layer of Teflon
fare pretty well, but exposed sections of cable need special
care and protection. Periodically, wipe the cables clean with
a rag, then coat them with a thin layer of oil or grease. On
any bike with split housing stops, pop the housings out of the
stops after creating some cable slack. To get the slack, open
the brake quick-releases and pull the housing out of the
stops. Then slide the housing down and lube the cable. This
is an easy, quick way to clean and oil the brake cables, which
will keep them operating smoothly and make them last
longer.
Depending on how often you ride and the conditions that
you ride in, you may choose to replace the cables at least
once a year. If you have supercables or don't ride much, it
isn't necessary. If you ride your bike a lot over demanding terrain, though, it's a smart thing to do because it will ensure
that you will always have cables in reliable condition.
Because brakes slow a bike through the friction that's
created between the brake pads and wheel rim, don't go crazy
lubing the calipers. Use a spray or drip lube, applying it on
the pivot points — the mounting bolt shank, the mating surfaces of the caliper arms (if there are any) and the return
spring anchor points. Then wipe off the excess.
What if you're caught without a spare cable?You may have
to ride temporarily with only one brake. In such a circumstance, your first inclination may be to favour the rear brake.
However, the front brake on a bicycle is actually more valuable than the rear brake. When both brakes are applied, the
front brake does 65 to 70 percent of the work. Therefore, if
the cable breaks on the front caliper, remove the cable from
the rear brake and install it on the front. This will give you
maximum braking power, under the circumstances, until you
get to somewhere you can replace both cables. Keep in mind
that the use of just the front brake will tend to pitch you forward more than the use of both brakes, so control your speed
so that it won't override your braking capabilities. If you must
brake rather quickly, slide your body as far back on the saddle
as possible to compensate for the tendency of your bike to
pitch you headfirst over the handlebar.
The brake system is extremely important and should be
treated with care and respect. When other parts stop working,
it usually means some inconvenience — the bike goes slower
or makes noise. If your brakes stop working, it may mean
you'll go careening into the next intersection and become a
hood ornament. Don't play games with your brakes. Keep
them in top shape all the time.
Regular Maintenance Procedures
PROBLEM: The
To keep the brake system working at optimum level, get into
the habit of cleaning the system after each ride. Wipe down
the rims with a damp rag (or alcohol if there are rubber
deposits on the rims) to keep the brake surface clean. A good
once-over with a clean rag will remove surface dirt from the
calipers. After completing these wipe-downs, use a clean
medium-bristle paintbrush to remove the dirt from the cracks
and crevices that are too small to get into with a rag or your
fingers. If it was a particularly dirty ride, wash the brake
system with brushes, rags, liquid detergent and warm water.
Use a minimal amount of lubricant because too much lube
causes dirt to stick to the calipers.
Finally, open the quick-releases and inspect the brake pads
for anything that may be imbedded in the soft material. If you
spot anything, carefully pick it out with a small screwdriver,
being careful not to slip and damage the tyre or rim.
TROUBLESHOOTING DISC BRAKES
pads constantly rub on the discs.
For a constant rubbing of the disc on one
brake pad, there are two possible solutions. Check the disc
where it enters and exits the casting of the caliper. If the
caliper body is centred over the disc, then you have a sticky
piston. Remove the wheel and brake pads. Hold a broad, flat
tool like a bladed screwdriver between the pistons, and give
the brake lever a few pumps to expose about 4 mm of both
pistons. This allows oil from inside the caliper to lubricate
the 0-rings. Spray the exposed parts of the pistons with
alcohol to clean them and let them dry. Use the screwdriver
to carefully push the pistons back into the caliper. Do not
notch the pistons — especially on their sides — use firm, even
pressure and don't pry or twist.
SOLUTION:
How to Cope with Brake Breakdowns
If the caliper body is not centred over the disc or if the
technique described above didn't cure the problem, you'll
need to repeat the alignment steps detailed in this chapter.
Regardless of how much care you take, the law of averages
says that one day your brakes may fail.The most common and
devastating occurrence on a ride, short of a broken lever or
caliper, is when one of your cables snaps. For that reason, we
recommend that when you go out on multiday rides, you
carry a spare brake cable along with a spare derailleur cable.
If your rubbing is an intermittent tick, your disc may be
bent. Though it's nearly impossible to get a bent disc perfectly straight again, you can get it pretty close with a few
common items. Remove the caliper (and adapter, if one is
used) from the frame or fork. Zip a plastic cable-tie around
230
ILLUSTRATED BICYCLE MAINTENANCE
the fork leg or stay, and snip it short. Now you have a
makeshift caliper to gauge where the disc is bent. Slide it
into place so there is a small gap between the end of the tie
and the disc, and slowly turn the wheel. Using an adjustable
spanner, gently bend the disc wherever it deviates from true.
The process is time-consuming and tedious, but it saves the
cost of replacing an expensive brake disc.
PROBLEM: Your
brakes squeak.
Some disc brakes just make noise and it can't be
avoided; it's the unfortunate truth. There are a few things you
can do to mitigate the annoyance.
SOLUTION:
Remove your brake pads and lightly scuff them on a
piece of sandpaper laid out on a flat surface.You don't need
to really dig into the pads; just a few light strokes are all it
takes to remove the glaze from the pads' surface.
Experiment with different types'of brake pads. Different
brake pad compounds and even different manufacturers'
interpretations of the same compound can make a big
difference in how much vibration is created. Be aware that
different pads will also perform differently. Weigh the costs
and benefits of ideal performance and low noise when
making your final decision.
Try a self-cleaning 'wave' disc. A wave-shaped disc like those
developed by Galfer will gently scrape the brake pads clean
with each pass. Some also speculate that the wave shape
pumps cool air through the pads, keeping the system from
overheating during prolonged braking.
PROBLEM: The
brake line is kinked.
There's no quick fix for a kinked brake line, but
it shouldn't be left unattended. A kink in the line can restrict
the flow of fluid to the caliper, or worse, can develop into a
leak. Get this fixed immediately If the kink is near the fitting
at either end and there is sufficient extra hose to do so, it's
possible to trim off the kink and reconnect the line. This will
require some new fittings and a brake bleed. If the kink is
further down the line or the hose is too short to trim,
replace the whole line.
SOLUTION:
PROBLEM: The
brakes feel vague or mushy.
SOLUTION: If the brake lever pulls all or most of the way
back to the grip, there are a few possible causes.
Check your brake pads. If they're worn down to less than 0.5
mm thick at any point, it's time to replace them. With new
pads in place, the slave pistons will be pushed back into
their cylinders, returning fluid to the master and renewing
brake feel.
Top off the reservoir. If your brakes have an external reservoir like those used by Shimano, Magura, Hope and others,
remove the cap and add fluid to the reservoir without performing a full bleed. Wrap a clean rag around the lever body,
leaving the cap exposed so it can be removed. With the cap
off, fill the reservoir about halfway. Give the brake lever a few
slow, steady pumps to evacuate any air and draw fluid down
into the system. Lightly tap the lever body to help air escape.
When there's no more evidence of air, top off the reservoir
and replace the cap.
TROUBLESHOOTING RIM BRAKES
When you squeeze the brakes, a pad drags
on the rim or stays closer than the other pad.
PROBLEM:
Check that the wheel is properly centred in
the frame. Check that the wheel is true. Does the brake
still stick? Centre the brake. Still sticking? Check the pads.
If they're worn unevenly they may be catching on the rim.
If so, carve or sand the pads flat.
SOLUTION:
PROBLEM:
The brakes squeak.
Make sure the pads are aligned correctly and
angle them so that when the brake is applied, the front tips
touch before the backs (this is called toeing-in the pads). Still
squeak? Try sanding the rims with medium emery cloth to
remove buildup and roughen the surface. Still squeak? On
mountain bikes, it's often possible to add a brake booster,
which may stop the squeak. This device attaches to the brake
posts, tying them together.
SOLUTION:
PROBLEM: The brake feels mushy, and the levers must
be squeezed too far.
Check the pads for wear, and replace them if
necessary. Make sure that the cable anchor bolt is tight — the
cable may have stretched. Tighten the adjustment by turning
the brake adjustment barrel on the lever or caliper anticlockwise.
SOLUTION:
PROBLEM: The brake is binding. You squeeze the lever,
but the brake doesn't feel right. It's harder to pull the
lever, and the brake doesn't snap back after you use it.
Inspect the cables (be sure to look inside the
levers at the head of the cable) and housing sections (look
for cracking and rust), and replace them if they're worn. If
the cables are okay, try lubricating them with oil or grease.
Also lubricate the pivot points on the brake.
SOLUTION:
PROBLEM: The
bike is braking poorly.
SOLUTION: Check for oil on the rims and pads. Inspect the
pads for wear and replace them. Replace pads that are old, as
they can harden with age and stop gripping the rim. Make
sure the cables are in excellent shape; replace them if needed.
PROBLEM: You
crashed and bent the brake or lever.
SOLUTION: If you can still ride, pedal home. If the part is
seriously bent, replace it — it will break when you try to
straighten it, or worse, when you're riding sometime in the
future. If it's a minor bend, you may be able to carefully
straighten the part by hand or with a pair of pliers.
PROBLEM:
One cantilever brake pad sticks to the rim.
PROBLEM: You brake and get a grabby, jerky feel from
the bike as it slows down.
If there is a triangular cable carrier at the
end of the main brake cable, try pushing it sideways on the
transverse cable. When the carrier is out of position, it can
cause one pad to hug the rim.
SOLUTION: You
PROBLEM: You
may have a ding or dent in your rim. This
will hit the brake on each revolution of the wheel, causing
an unnerving jerky sensation. Remove the dent and get
the rim as straight as possible. Replace the rim if it can't
be fixed.
PROBLEM: The brake feels too tight. Squeezing and
releasing the lever barely moves the brake.
The cable adjustment is too tight. Look for a
housing section that's twisted somehow or a housing end
that's not seated in its frame stop. Housing okay? Try
loosening the adjustment barrel at the lever or caliper
(turn clockwise). Make sure there's at least 3 mm clearance between the pads and rims, more on cantilever
and direct-pull brakes.
SOLUTION:
PROBLEM: You installed cantilevers and now one is tight
on its post and it won't pivot freely.
SOLUTION: You
may have overtightened the bolt, which
bulges the frame post it's screwed into, causing binding.
Remove the bolt and brake arm, and sand the post until the
brake fits on easily again. Don't overtighten the bolt.
PROBLEM: You've removed the cable for maintenance
and discovered that the brake action is jammed. It seems
stiff and barely moves when you try to squeeze it by
hand.
Corrosion has seized the brake. Dismantle it
and sand the corrosion from the brake and brake mount(s)
with sandpaper. Then lubricate all moving parts (keep lube
away from the pads) and reassemble.
SOLUTION:
SOLUTION:
crashed and broke the cantilever brake.
Now one side isn't attached to the frame.
Usually this can be repaired with a cantilever
repair kit, which includes everything needed to repair the
frame post and reattach the cantilever. Shops may carry
these kits, or contact Loose Screws.
SOLUTION:
PROBLEM: On long descents, you hear a disconcerting
grating sound when braking steadily. It sounds like
metal on metal, and the braking action is poor.
Check the pads. They may have worn out.
You might also have bad pads (even some new pads are
inferior); replace them. The pads may have been contaminated by aluminium from the rim or have road grit
embedded in their surface. Pick out the debris with an
awl or replace the pads.
SOLUTION:
PROBLEM: Turning the handlebar sideways causes the
rear brake to grab the rim.
SOLUTION: The
cable housing may be too short or it may
have got twisted somehow. Fix the housing so that you can
turn the handlebar as needed without causing the brake to
be applied.
232
ILLUSTRATED BICYCLE MAINTENANCE
Brake Lever Adjustment
and Removal
i
On a typical drop-handlebar bike, the levers cannot be removed or
relocated without the handlebar tape first being unwound from the
lever clamp. You may as well completely remove the old handlebar
tape at this time and replace it with new tape after the levers are back in
place. To completely remove a lever, first release the cable that is attached to it.
Loosen the small bolt that anchors the cable to the brake calipers and pull the
cable free (see photo).
("S Unhook the fitting on the upper end of the cable from its seat in the
lever (see photo). Pull the cable all the way out of the lever body and
cable housing. If you wish only to relocate a lever on the handlebar
Lif
rather than remove it, you may be able to actually leave the cable inside the
lever body. Unhook it from the lever and pull it out of the way while you
loosen the clamp.
........
/
.
When you're ready to loosen the lever clamp, squeeze the lever
against the handlebar and look inside the lever body. You'll see a
th...../ bolt or screw that's used to fasten the clamp to the bar. Find the
appropriate tool to remove this fastener (see photo). You'll probably need
a flathead screwdriver, a hex key or a thin-walled socket spanner.
Loosen the lever clamp bolt enough to allow you to reposition the lever or
to slide it around the bend and off the end of the bar. If you like, when both
levers are off, clean the bar of any residue left behind by the old tape.
BRAKES 233
Brake Cable Installation
1
41.,
Simple as it may appear, replacing a brake cable is a task not to be
taken lightly. There are several considerations to be made before the
job even begins. For starters, decide which lever to connect to which
brake. The recommended rule is to connect the right lever to the rear brake,
and the left to the front. Feel free to experiment, but always be aware of
which brake is connected to which lever.
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2
,
Once you've reached a decision about the lever-to-brake connection,
determine how long the cable housing should be. Many new bikes
come fitted with excessively long housing, which means large cable
loops that can be a nuisance to the rider. Cable that is longer than necessary
also creates unneeded friction in the braking system. Ideally, the brake cables
should arch as low as possible under the bicycle handlebar. Avoid going to an
extreme though, if you make the housing too short, it will bend sharply and
kink the cable. Short housing can also obstruct the proper movement of the
handlebar. Pick a length that will allow your handlebar to move through its
full range of motion without creating kinks. Mark the position on the housing
where you wish to trim it, and cut the vinyl covering with a sharp knife.
3
Use a sharp pair of cable cutters (or diagonal cutters) and work one
jaw between coils so that you can make a clean cut through a coil
without smashing the housing.
234
ILLUSTRATED BICYCLE MAINTENANCE
4
_
5
After trimming the housing, file the cut end smooth to prevent the
possibility of it snagging and damaging the cable (see photo). Use
an awl to reopen the plastic liner inside the housing.
Get out one of your new cables. Unless these cables were made
specifically for your brake system, they may be universal cables,
which have a different fitting attached to each end. Determine which
fitting you need by looking inside the lever at the rotating barrel into which it
must fit. Trim away the fitting that you do not need.
_
6
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Lubricate the cable before running it through the housing. The
medium-weight grease you use elsewhere on the bike will work fine,
as will some oil. Just put a little on your fingertips and pull the cable
through to coat it lightly. Squeeze the lever open and thread the cable through
the lever body and into the cable housing.
Push the cable on through the housing, but do not fasten it to the brake yet.
Leave yourself some slack at the upper end so you can hook the cable fitting
onto the lever. Rotate the cylinder as needed and tug on the loose end of the
cable to make sure the fitting is properly seated in the lever (see photo).
BRAKES 235
7
Thread the loose end of the cable through the housing stop and pull
8
If you have sidepull brakes, run the end of the cable through the
on it to seat the housing against the stop (in this case, the housing
stop is the adjustment barrel on the front brake).
anchor bolt. If you have centrepull brakes, make sure the fittings at
each end of the short stirrup cable are properly seated in the slots
provided for them in the upper ends of the caliper arms. Run the end of the
main cable through the anchor on the yoke used to lift up the stirrup cable.
You may wish to tighten the nut with your finger to prevent the cable from
pulling free until you are ready to firmly anchor it (see photo).
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9
- MUM1111111
Before you securely anchor the cable, check back over the entire
braking system. First, find the cable adjusting barrel. On sidepulls, this
barrel may be located either at the lever end or the caliper end of the
cable housing. A few systems have adjusting barrels in both places. On centrepulls, the adjusting barrel will probably be on the cable housing hanger.
Thread the barrel all the way down, then back it off a couple of turns (see
photo). This will leave you plenty of room to take up slack in the cable as it
stretches with later use.
236 ILLUSTRATED BICYCLE MAINTENANCE
10
f your brake system is equipped with a quick-release lever,
hake sure it is closed so the calipers can be adjusted to their
)perating position. Check again to make certain that the fitting
at the upper end of the cable is properly seated in the lever.
11
Use a toe strap or a third-hand tool to hold the calipers shut
against the rim while you pull up the slack in the cable and
anchor it firmly.
Release the calipers and squeeze the lever firmly a few times to stretch the
new cable. If this immediately produces a good deal of slack in the system,
fasten the calipers back against the rim, loosen the anchor bolt, pull the cable
tight and reanchor it.
After prestretching the cable, you should be able to handle some slack by
turning the adjusting barrel so that it moves away from the brake calipers,
thus tightening the cable. When you reach the point where there is very little
room left for fine-tuning the cable length by means of the adjusting barrel, it
usually indicates worn-out brake pads.
1
A new brake cable will almost certainly be longer than necessary. After the installation process is complete, allow 3 to 4 cm of
cable to extend beyond the anchor bolt and trim away the rest
(see photo). The cut end of a new cable is likely to fray if left unprotected. To prevent this, cover it with a little aluminium or plastic cap made for this purpose.
Another possibility is to coat the tip of the cable with solder. To solder the cable
end, use alcohol to clean away all grease and dirt. Stick the cable tip into flux,
then heat it with a soldering gun. When it starts to sizzle, hold solder against
it. As the solder begins to melt, rub it up and down to coat
the area, then wipe it smooth with a damp rag.
BRAKES 237
Mountain Bike Lever
and Cable Installation
1
Removing and installing mountain bike brake levers means dealing
with the handlebar grips. If you're replacing a worn pair of grips,
simply cut off the old ones with a utility knife. If you want to save the
old grips, slide a small screwdriver beneath an edge and drip in a little alcohol.
Twist the grip a bit and add a little more alcohol until the grip slides off the bar.
Loosen the lever clamping bolt with a hex key and slide the levers off the handlebar. When installing new levers, consider the order of assembly of the shift
levers first. Some shifters go on first (thumb levers), some brake levers do (twist
grips). Before tightening the lever, place it so that it does not protrude past the
end of the bar (see photo). That will ensure that if you crash, the bar will hit
before the lever, so the lever is less likely to be damaged.
•=31111E-
2
Even more importantly, adjust the lever so that it's in line with the natural bend in your wrist when you sit on the seat and rest your hands
on the grips (see photo). You don't want to be squeezing the brake
lever with bent wrists. When the lever is positioned correctly for you, tighten
the clamping bolt. Install the shifters, if necessary, and the grips. Lubricate
them with alcohol if needed. They'll be slippery at first, but the alcohol will
evaporate quickly, and the grips will stick.
3
To install the cable in the levers, turn the adjusting barrels to line up
the slots inside. Squeeze the lever to find the cable holder, and insert
the cable end (grease it first) in the holder (see photo). Place the cable
in the slot in the adjusting barrel and brake lever, and turn the adjuster clockwise to keep the cable in place. Now squeeze the lever while pulling on the
cable to make sure it works smoothly. If not, look closely to find problems and
reinstall if necessary. When running the cables, copy the old housing path.
Usually, the only tricky section is where the rear brake exits the lever. It can
pass on either side of the stem. Try it on both sides and use the position that
provides the least resistance when the bar is turned from side to side. Usually,
this means that the housing runs around the left side of the stem.
238
ILLUSTRATED BICYCLE MAINTENANCE
Aero Lever and Cable Installation
1
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all111111111M11
When installing any species of aero levers, it's important to seat the
housing and ferrule (if there is one) carefully inside the lever. If either
is not secure, the cable can bind and reduce the brake's effectiveness.
With the brake lever off the handlebar, grease the cable lightly and thread
it through the lever, the ferrule and the housing (see photo). The cable end
should be cut cleanly and travel smoothly through the housing. If it does not,
recut the cable end with cutters made for the purpose. Make sure the ends of
the housing are free of burrs; recut the ends if necessary.
2
Thread the brake cable through the brake caliper's adjustment barrel
and anchor bolt. Use a third-hand tool or toe strap, or squeeze the
caliper with your hand and pull on the brake cable until the head of
the cable and the housing seat inside the lever. Tighten the anchor bolt (see
photo). Remove the third-hand tool so the brake spring tension will hold the
housing and ferrule in place inside the lever.
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3
Move the housing to the slot for it inside the lever, and wiggle the
lever onto the handlebar. To ease lever installation, roll back the
rubber hood. Tighten the lever in place (see photo). The most common
way to position levers is to hold a straight edge against the underside of the
handlebar and slide the lever so its tip rests on the straight edge. The lever
should also face directly forward rather than point off at an angle. Secure the
levers by tightening the bolt inside the lever body with a hex key.
BRAKES 239
4
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Ali
1911111■11111111111111111
Aero lever cable housing works best when the rear section travels in
front of the stem before returning to the top tube cable stop. This loop
will provide enough slack for you to turn the handlebar without
binding. The front brake housing should go through this loop to the front brake
(see photo). The cable routing should always follow smooth, gradual bends for
optimal braking action.
5
Use electrical tape to affix the housing to the underside of the handlebar. Trim excess housing so the brake is as responsive as possible. To
do this, loosen the cable anchor bolt to release the brake cable, grasp
the head of the cable inside the brake lever with needlenose pliers and pull the
cable out of the housing enough so you can cut off a section (see photo).
Again, make sure there are no burrs on the end of the housing. Use cable
cutters or a file to fix this if necessary. Be careful not to cut off too much
housing, which would cause the brakes or handlebar to bind.
6
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MIN.
RIMIK
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Push the cable back through the housing and the brake anchor bolt.
Use the third-hand tool to compress the brake caliper and pull on
the end of the cable while you tighten the anchor bolt. Wrap the bar
with handlebar tape. It's easier to wrap it around the brake levers if you roll
the rubber hoods back.
240 ILLUSTRATED BICYCLE MAINTENANCE
Sidepull Installation
I
To remove the caliper of a sidepull brake, loosen the cable anchor bolt
and free the end of the cable. Loosen and remove the nut on the rear
end of the mounting bolt that runs through the brake body. Thread the
nut off the end of the bolt, then pull the brake body away from the frame (see
photo 2). If you have removed the brake to service it rather than replace it,
clean it thoroughly. Use a rag dipped in solvent and a brush to loosen the
grease and dirt that's on the surface of the calipers and hiding inside all
nooks and crannies.
2
..g.t.......,-
4......
Unless you're using something mild like alcohol, keep the solvent
away from the rubber brake pads. Better yet, remove the brake shoes
to clean the pads separately. Since oil and grease have a tendency to
attract dirt, use them only where needed. On sidepull brakes, that means
only at the pivot points and the spring anchors on the back of the calipers.
To minimize the possibility of getting lubricant on your brake pads, use
grease rather than oil on the spring where it rubs against its anchors.
Because it is difficult to work grease into the pivot area without dismantling
the brake, spray those points with a small amount of lubricant containing
Teflon (see photo 3).
To install a brake, insert the mounting bolt through the hole in the
frame and thread on tile mounting nut. Tighten the nut, but leave it
loose enough for the brake to be centred over the wheel by hand.
Reconnect the brake cable to the brake calipers and adjust the cable length
by following the instructions starting on page 233.
Before you can properly align the calipers, ensure that the wheel is true and
centred in the frame. If the wheel is out of true, no amount of brake adjustment will give you good performance. Also check the relationship of the
caliper arms to each other. If they're too tight, they will not spring back after
you release the lever.
BRAKES 241
4
If the caliper arms are too loose, they will vibrate excessively when
you press them against the rim of the moving wheel. They should be
as tight as they can be and still operate freely. The tightness of lesser-
quality calipers is controlled by a nut or pair of nuts on the front end of the
mounting bolt. Because this part of the bolt functions as the pivot for the
calipers, it is often referred to as the pivot bolt. If there are two nuts, the outer
nut must be loosened and the pressure on the calipers must be adjusted with
the inner one. Stop tightening the inner nut just before the calipers start to
show resistance to pivoting, then lock the two nuts against one another to
maintain the adjustment (see photo).
. . . . . . . . ._
5
If your brakes have only a single nut or bolt head in front, turn that
to adjust the caliper tension. Rotate the brake to centre the pads.
Hold the brake in that position while you snug up the mounting nut
(see photo).
Squeeze the brake lever a few times to see if the brake pads are striking the
ri m at the same time and whether the brake remains centred after being
used. If the brake needs minor centring and it's a modern dual-pivot model,
look for a centring screw on top of or on each side of the caliper. Turning
these small hex screws will move the brake slightly, centring it over the wheel.
6
AMP
–
On older sidepulls, hold the brake steady again while you snug up
the mounting nut a bit more. Then turn both wrenches together to rock
the entire brake body in the direction needed to centre it.
242
ILLUSTRATED BICYCLE MAINTENANCE
Basics of Disc
Brake Maintenance
1
Disc brakes work best when tiny particles of brake pad material are
embedded in the surface of the disc, so in general it's best to not clean
:;- them too often. Keep in mind that disc brake pads are extremely sensitive to oil contamination: even trace amounts of oil from your fingertips can be
enough to affect your braking. The best solution is to simply not touch the
discs and prevent oil splatter from reaching them. But this is not a perfect
world. To clean your discs in the event of contamination, use a solvent that
specifically states on the label that it is safe for cleaning brake discs. In the
absence of such a product, plain old pharmecutical alcohol works perfectly.
Soak a corner of a clean rag with your chosen solvent and wipe the entire
disc. Then, with a clean, dry corner of the rag, wipe the disc again.
"41118
„----,
If oil gets on your disc brake pads, you may be able to salvage them
by rubbing them lightly across a piece of sandpaper or emery cloth
,a‘movio laid out on a flat surface. If the pads have gotten soaked with oil or
if heat is applied after the pads became contaminated (such as applying the
brakes while riding), you'll likely have to replace them.
3
Proper alignment of disc brake calipers is critical to their performance.
If standard aligning techniques still leave your brakes feeling vague
and mushy, you may need to have your brake bosses milled. Milling
is the process of shaving material from the disc brake tabs on your frame to
make their mounting surfaces perfectly parallel to the brake disc. The tools
to perform this task are expensive considering how infrequently a home
mechanic might use them, so it's probably wise to leave this job to your
local bike shop.
BRAKES 243
4
A kinked hydraulic line is more than an eyesore. The inner lining
can also be compromised, making a brake failure likely. If the line is
kinked near a fitting and there is sufficient extra line to do so, trim
away the affected portion of the line and bleed the system. If the kink is
too far from a fitting to do this, there is no choice but to replace the line.
5
Exposure to rocks and logs means that brake discs will get bent. It's
just the way it is. If yours is tweaked, all is not lost. Remove the
caliper, zip a plastic cable tie around the fork leg or seatstay and snip
the end short to create a makeshift truing caliper.
With your caliper in place, you can now gauge where and how far
the disc is bent. Use a set of disc truing tools or an adjustable spanner
to straighten the disc. It may never be perfect again, but it can
certainly be made passable.
244
ILLUSTRATED BICYCLE MAINTENANCE
Mechanical (Cable-Actuated)
Disc Brake Installation and
Setup (Avid and similar)
1
Avid disc brake calipers are mounted using a set of hemispherical
washers. This ingenious mounting system allows the caliper to be
aligned in all directions, compensating for inconsistencies in a frame's
or a fork's brake mounting tabs. Avid calipers come out of the box with their
adapters already mounted to the caliper. The sequence of the washers is
critical to the function of the Tri-Align system, so don't remove the caliper
from the adapter unless you have taken note of the proper orientation of
the hemispherical washers. Bolt the caliper and adapter into place on the
frame or fork. If you're readjusting an existing system, remove the brake
cable from the caliper.
Loosen the bolts holding the caliper to the adapter about one turn. The
caliper should slide freely from side to side and should rotate freely in the
hemispherical washers.
Each brake pad has a red dial adjuster. Turning it clockwise moves the
pad closer to the disc; anticlockwise moves it away. Use these dials to
,
(4 clamp the disc between the pads, roughly in the centre of the caliper
body. In small increments – one, then the other – tighten the bolts holding the
caliper to the adapter. Watch the caliper closely as you're doing this, making
certain that it doesn't try to 'walk' side to side from friction with the bolt.
Turn the outside dial adjuster anticlockwise, moving the mobile brake pad as
far from the disc as it will go. Turn the inside dial adjuster just a few clicks
anticlockwise. Push the caliper's lever arm by hand to ensure that the pad is
pushed back, and give the wheel a spin. If there is any rubbing, turn the
inside adjuster one click anticlockwise and repeat until there is no more contact. There should be a gap of less than 0.5 mm between the fixed pad and
the disc.
Turn the outside dial adjuster clockwise, a few clicks at a time, and push the
lever arm by hand until it stops at a point about halfway through its travel to
the cable stop.
3
Anchor the cable in place using a 5 mm hex key. Use a fourth hand
tool to simultaneously pull the cable and push the caliper's lever arm
about one-quarter of the way through its travel. Give the brake lever
a few firm squeezes to settle the housing and pads into place, and then repeat
your cable adjustment. You'll find it's best to make fine adjustments to lever
feel at the cable anchor, rather than using the adjusting barrel on the lever.
The barrel adjuster is there primarily to quickly adjust for pad wear while out
on the road or trail.
4
Cut the free end of the cable no more than 20 mm from the cable
anchor. Too long and the end of the cable could swing into the disc,
locking up your wheel and sending you flying. Crimp the cable end
to prevent fraying, and you're good to go.
246
ILLUSTRATED BICYCLE MAINTENANCE
Hydraulic Disc Brake Installation
and Setup (Hayes and similar/
1
Hayes brake calipers incorporate a two-part system with the caliper
mounted to the frame or fork using an adapter. The only two exceptions are Manitou forks, which are designed to allow Hayes calipers to
be directly mounted, and mountain bike frames from the mid- to late-1990s
that used a Hayes-specific mount on the left chainstay. In either of those cases,
the procedures described here still apply, though the adapter is not present.
Use a 5 mm hex key to ensure that the two bolts holding the adapter to the
frame's or fork's mounting tabs are tight. Use a 5 mm hex key to loosen the
two bolts holding the caliper to the adapter by about half a turn. The caliper
should float freely from side to side. Disengage the hydraulic line from its
guide on the chainstay to help the caliper move more freely.
2
Wrap an elastic band over the handlebar and brake lever. This will
apply constant pressure to the brake pads, clamping them on the
disc. Assuming that both pistons of the caliper are moving an equal
distance, the caliper should centre itself on the disc.
BRAKES 247
3
In small increments - one, then the other - gradually tighten the
bolts holding the caliper to the adapter. Watch the caliper closely as
you're doing this, making certain that it doesn't try to 'walk' side to
side from friction with the bolt.
4
Remove the elastic band holding the brake lever. Looking through
the caliper from behind, you should be able to see daylight between
both pads and the disc. Hold a sheet of white paper on the other
side of the caliper to make this easier to see.
248
ILLUSTRATED BICYCLE MAINTENANCE
Hydraulic Disc Brake Installation
and Setup (Shimano, Hope,
Magura and similar)
l
—
-..-
Magura, Hope and Shimano disc brakes, among others, are aligned
using very thin washers called shims between the frame's or fork's
mounting tabs and the caliper. Shimming a caliper sounds simple
enough to do - and it can be if you're patient. Fumbling around with small
parts in tight spaces can be frustrating, though, so take a few deep breaths
and rest assured that when it's done right, you may well never need to touch it
again. Set the caliper in place by turning the bolts in just 2 or 3 threads. The
caliper should be able to float from side to side. Disengage the hydraulic line
from its guide on the chainstay to help the caliper move more freely.
2
Wrap an elastic band over the handlebar and brake lever. This will
apply constant pressure to the brake pads, clamping them on the
disc. Assuming that both pistons of the caliper are moving an equal
distance, the caliper should centre itself on the disc.
BRAKES 249
3
Determine the correct number of shims for each mounting bolt. This is
a trial-and-error process, and it is likely that each mounting bolt will
require a different number of shims. The correct number is however
many will fit snugly between the mounting tabs of the frame/fork and caliper.
Magura and Hope supply washers that require the removal and reinstallation
of the mounting bolts to be put in place. Shimano supplies their brakes with
Y-shims that can be installed easily using a pair of needlenose pliers. Tighten
the mounting bolts using a 5 mm hex key.
4
Remove the elastic band from the brake lever and check for brake
pad clearance in the caliper. You should be able to see daylight
between both brake pads and the disc. Hold a sheet of white paper
on the other side of the caliper to make this easier to see.
250
ILLUSTRATED BICYCLE MAINTENANCE
Cantilever Installation
and Adjustment
1
Mountain bikes are often equipped with flat handlebars, regular brake
levers and cantilever brakes. Since mountain bike handlebars are not
wrapped with tape, brake levers can be relocated or replaced fairly
quickly. To reposition a lever, locate and loosen the clamp bolt (see photo).
Move the lever to the desired place and retighten the clamp.
2
The cantilever brakes used on mountain bikes, tandem bikes and most
loaded touring bikes are mounted differently to sidepull and conventional centrepull brakes. Each front cantilever is fastened by a bolt to a
metal post that is brazed to the front side of each fork leg (see photo). Cantilevers on the rear are attached to posts brazed on the backs of the seatstays.
The brake pads on cantilevers are slightly different from those on caliper
brakes. The posts that extend from the backs of the shoes on cantilevers are
fairly long and are used to adjust the distance of the shoes from the rim.
3
IIIIIIIII■1F-
.IMI.
.111
IIIIM■
When installing a new set of cantilevers or readjusting an old set,
make sure that the wheel is true and centred in the frame. Set all the
brake pads equidistant from the rim. You'll probably need a hex key
for the head of the pad mounting bolt and a combination spanner for the nut
it its end (see photo).
(here are two factors to take into account in determining the proper setting
3f the pad. First, the pad should be turned so that it is parallel with the rim.
Second, it should be set so it solidly contacts the rim when the arm is pushed
•owards the wheel. Too high, and it may strike the tyre; too low, and it may
live into the spokes.
4
Cantilever brakes make use of a short cable - known as the linking,
transverse, stirrup or straddle cable - to connect the two braking
arms. This cable may have a permanent fitting on only one end. If
so, the other end is anchored by a bolt and the cable length is adjustable.
Hook the end with the fitting into the cantilever arm that has a slot to receive
it (see photo). Thread the other end through the anchor bolt found on the
other arm. Where you anchor it depends in part on the frame. As a general
rule, set the stirrup cable length such that when you pull up on its centre, the
angle formed there is less than 90 degrees.
I.
5
Give the main cable a light coating of grease, then push it through the
housing and seat the fitting on its upper end into the groove provided
for it on the lever. Hook the yoke around the centre of the stirrup
cable and run the loose end of the main cable through its anchor bolt. If it's a
Shimano cantilever, the cable may not end at the yoke - it may pass through it
and end at the anchor on one brake arm.
Before anchoring the main cable at the yoke or at the arm, thread the
adjusting barrel at the lever end down almost against the lever to provide
plenty of adjustment space as the cable stretches (see photo).
6
Hold the cantilever arms against the wheel rim, pull the main cable taut
and tighten the bolt to anchor it (see photo). If the cable passed through
the yoke on its way to the anchor on the brake arm, tighten the nut at
the yoke, too, after making sure that both sides of the cable are the same length.
Squeeze the brake a few times with the lever. Make further adjustments in pad
position and cable adjustment if needed. If the brakes do not contact the rim
at the same time, try shifting the position of the yoke along the stirrup cable
towards the slower side. If that doesn't solve the problem, look for centring
screws in the sides of the arms. Or, release the straddle wire to open the brake,
and rock the sticky arm away from the rim to increase spring tension.
252
ILLUSTRATED BICYCLE MAINTENANCE
Direct-Pull Cantilever (V-Brake)
Adjustment
1
Direct-pull cantilevers are pretty easy to adjust. One caution though:
they require a special, direct-pull-compatible lever that pulls more
cable than old-style levers. You won't get good performance without
one. However, there are adapters available that convert non-direct-pull levers.
Get some if you plan to use incompatible levers.
Wheel problems will cause poor brake adjustment. Make sure your hoops
are true and centred in the frame before adjusting the brakes (see photo).
2
When adjusted correctly, direct-pull cantilever brake arms should be
close to parallel to each other. To achieve this with different rim
widths, each brake pad has a thick and a thin washer (see photo).
Place the appropriate washers for your rims between the pads and arms (keep
one inside and one outside the brake arm). Then adjust the cable at the anchor
bolt until the arms are close to parallel.
3
When working on the pads, it helps to release the spring on the side
you're working on so the other side will pull the pad into the rim.
Sight along the pad. Unlike all other types, which are normally toed-
in slightly, you should adjust direct-pull pads so that they strike the rim flat and
are in line with the centre of the rim (see photo). If not, loosen the 5 mm fixing
nut, adjust the pad, tighten it securely and then reattach the spring.
BRAKES 253
4
If one pad stays closer to the rim when you squeeze and release the
brake, use the small Phillips screws at the base of the arm to centre
the arms. Clockwise turns increase spring tension, moving the pad on
that side away from the rim, and anticlockwise turns loosen tension.
5
11■1•11111•11M-
41115.
„....
It can be challenging to quiet squeaky direct-pull brakes. Try these
tricks: check the mounting bolts to ensure that the arms are tight in the
frame. If that's not the problem, scuff the rim sidewalls with emery
cloth or the sandpaper in your patch kit to break the glaze. Still noisy? Take the
bike for a ride and take along a 5 mm hex key. Under these circumstances, you
can experiment with different brake pad toe-in angles to see if you can shut
them up. (The front of the pads should strike the rim before the rear.) No? Try a
different brand of brake shoe. Howling anyway? Purchase and install a 'brake
booster', an add-on piece that joins the two brake bosses and stiffens things up.
254
ILLUSTRATED BICYCLE MAINTENANCE
Brake Pad Maintenance
1
The brake pads are small, but they're vital to braking. Keep them close
to and aligned with the rim so they don't hit the tyre when you brake
(which can cause a flat) or dive into the spokes (which might cause a
crash). Bad pad alignment also causes poor braking, as well as squeaking and
chattering when braking.
It is also important to keep the brake pads clean. Small bits of grit get pressed
into the pads during braking and when enough grit gets in there, the pads
become terribly abrasive, so that you actually wear out your rims if you keep
braking with them. To keep the pads clean, use an awl or sharp tool to pick
out any debris stuck in them (see photo).
Watch for uneven wear, too. Sometimes a pad will develop a lip if
it's aligned slightly too low or too high. This may cause the brake to
stick when it's applied because the overlapping bit of pad gets stuck
beneath the rim. Refurbish the pad by trimming it flat with a sharp knife (see
photo). If it's a small defect, smooth it away with sandpaper.
Pad wear varies greatly. It's actually possible to wear out a set in a single
off-road ride if it's muddy enough! They may last several years on a minimally used road bike, however.
Most pads have grooves on them to help gauge wear (see photo).
When the grooves begin to disappear, replace the pads. Also replace
the pads any time they are worn
to
the point that the metal pad
holders are close to touching the rim – if the holders strike the rims, they'll
damage the braking surface. When this happens, you'll lose most of your
braking power and hear a gritty scraping sound.
...... a
4
There are two basic pad types: one-piece pads that must be
unscrewed and cartridge pads, on which the rubber pieces can be
pulled or pried out of their holders so that you can slide in new ones.
A cartridge pad makes replacement much faster and simpler because popping in new pads doesn't require realigning the holders. If your bike has
nonreplaceable pads, do yourself a favour when they wear out and upgrade.
To install a new one-piece pad, do one side at a time so you can compare
the alignment with the other side. On all brakes except direct-pull cantilevers,
toe-in the pads very slightly. This means angling the pads so the front ends
strike the rim first, which prevents squeaking.
5
To install a cartridge-style pad, look for a set screw or small press-in
pin holding it in place. If there isn't one, pry the old pad out by
pressing a thin-blade screwdriver behind it and working the pad free.
Then slide in a new pad. If it goes in supertight, press it in with water-pump
pliers (see photo).
6
If the pad has a retaining screw or pin, remove it, extract the pad,
slide the new one in and reinsert the pin. You may have to press on
the end of the pad to get the pin to seat fully. When seated, the tip of
the pin should be visible on the bottom of the pad holder.
CHAPTER 14
Handlebars and
Stems
The frame is the foundation; the wheels make it a bicycle.
Derailleurs and drivetrain make it go, and brakes make it stop.
But the handlebar and stem make it fit — and if the bike
doesn't fit, you're getting only half the experience.
With the right choice of stem and handlebar, even a frame
that's a little too big or a little too small can be made to ride as
if it was custom-tailored to you. Or, you can start with a bike
that was well fitted for one purpose and create something different with it. We often see older lightweight
racing bikes that have been retired from
competition and become stylish commuting bikes or coffee-go-getters
simply by switching to a more relaxed
handlebar and stem combination.
inch) quill. If these numbers don't seem to correspond, that's
because the quill dimensions given here in millimetres fit
inside fork steerers with the given inch dimensions. Confusing? Yes. But if you ask your local shop for a 1X-inch quill
stem, they'll know exactly what you're talking about.
If you don't have an inside micrometer or inside calipers,
simply borrow a stem of each diameter and try them out, or
take your bike along to the bike shop to get the proper fit.
Unless yours is an older French road bike, it's
unlikely you'll have 22.0.
Threadless Style
Threadless stems have eclipsed quill sterns
in recent years as the standard design.
Stems of this type can be found on
almost all bikes in all price ranges, but
The Right Stem
are most common on mid- to highBefore purchasing a new stem, you
priced road and mountain bikes. A
have to figure out what type fits on
threadless
stem clamps to the outside
your bike. There are two main types:
of
an
extended
fork steerer tube,
quill-style and threadless-style.
One-piece handlebar-and-stem combinations are
rather than gripping the inside the
incredibly lightweight, but they aren't as adjustable
way a quill stem does.The easiest way
Quill - Style
as individual components.
to
identify a threadless stem is by
A quill-style stem is L-shaped and was
locating a pinch-bolt or a pair of
commonly found on all types of bikes
until the 1990s when threadless stems gained popularity. Now pinch-bolts on either side of the stem where it grips the fork.
Threadless stems also come in a variety of sizes, though 1X
quill stems are most commonly found on casual-type bikes like
hybrids and children's models. One part of the stem fits inside inches is by far the most common. In fact, 1-inch threadless
the fork, with an expander wedge on the bottom. When the was used for such a brief time that most manufacturers of
expander bolt running through the centre of the stem is tight- stems simply supply a shim to fill the void between a 1-inch
ened, the wedge pulls up inside or alongside the stem, jamming threadless steerer and a 11-/inchstem8,ra uplying
the stem inside the fork.You can identify this stem by a 6 mm specific models anymore.
For mountain bikes there is a new, oversize option called
hex bolt, or a 12 or 13 mm common bolt on top of the stem
1
-inch) that takes advantage of a very large
directly over the fork. (Don't be confused by the 5 mm hex OnePointFive (1 Z
diameter steerer tube to enhance strength and minimize flex
bolt in the cap that is found on threadless stems.)
The diameter of your stem must match your fork. For quill for long-travel suspension forks.
It must be said that the threadless system takes better
stems, first determine whether you have a fork that requires a
French-dimensioned 22.0 mm, the fairly universal 22.2 mm advantage of material properties than threaded-type steerers
(commonly called 1-inch), the 1990s standard for mountain and quill stems, creating a connection between stem and fork
bikes 25.4 mm (commonly called 1X-inch), or short-lived that is at the same time lighter and stronger than a traditional
oversize diameters like 28.6 mm (11/4-inch ) or 32 mm (13/8- quill-type connection.
•
258
ILLUSTRATED BICYCLE MAINTENANCE
Raising the Bar
■ HANDLEBAR
■ HEADSET TOPCAP
■ HEADSET STARNUT
PINCH BOLTS
STEM
■ STEM FACEPLATE
HEADSET
HANDLEBARS AND STEMS 259
There is a drawback, though, to the threadless design.
Once a stem height is decided upon, the steerer is cut to
length, making it impossible to ever raise the handlebar
without changing the stem entirely. As a result, it is common
practice to 'stovepipe' the steerer (cut the steerer long and take
up the excess with spacers on top of the stem) so that the
stem height can be played with until the ideal level is found.
Remember, you can cut the steerer all you want, but you can
never make it longer.
Bar and Stem Compatibility
After determining which stern fits your fork, you'll need to
figure out whether that stem fits your handlebar or viceversa. There were once several different diameters of road
handlebar: 25.4 mm was the Japanese standard; 25.8 mm the
standard for the manufacturer TTT; and 26.4 mm was the
standard for bars manufactured by Cinelli. While Nitto still
holds true to the 25.4 mm diameter, it's not as great a problem
as it could be since this is also the original standard for
mountain bike handlebars and stems. All others had just
settled on 26.0 mm as a common standard when a new oversize standard was introduced: 31.8 mm.
At present, both 31.8 mm and 26.0 mm can commonly be
found on new road bikes, with 31.8 mm bars and stems generally specified on higher-priced models.
Mountain bike handlebars and stems all had 25.4 mm
handlebar clamps until very recently. About the same time
that the 31.8 mm standard was introduced for road bikes, it
was also introduced for mountain bikes.
Both styles of bikes are able to take advantage of different
aspects of the oversize handlebar diameter. Road handlebars
can shave weight while maintaining strength and rigidity.
Mountain handlebars can maximize strength with little or no
weight penalty.
There is another benefit of common dimensions for both
steerers and handlebars on road and mountain bikes. The
variety of stems available essentially doubles for consumers
without increasing inventory for suppliers and retailers. So a
cross-country mountain bike racer looking for a lightweight
stem and a low riding position can use a road stem, while a
casual road rider interested in a strong, upright stem for some
light touring can install a mountain stem.
Once you know what stem will fit your fork and handlebar,
it's time to determine the length and angle of extension that's
correct for your body. Unfortunately, there's no simple or foolproof method for doing this.The correct stem length is predicated on several variables that don't always correlate in the
same way. The variables include torso length, lower- and
upper-arm length, saddle position, top tube length, choice of
handlebars and intended purpose for the bike.
Getting a good fit between rider and bike begins with the
selection of a frame. Once that choice is made, fine-tune your
bike fit by adjusting the saddle up and down and, to a limited
degree, fore and aft. These adjustments can have a huge affect
on leg and pedal position.
Once the saddle position is set, the proper handlebar position can be determined in relationship to it. One traditional
technique for road bikes is to place the back of the elbow
against the nose of the saddle, and extend the forearm and
hand towards the stem and handlebar. As a general rule, the top
of the handlebar should lie a few centimetres beyond the tips
of the fingers.This is a fairly good place to start.
You might want the bar a little closer to allow for easier
breathing and a more upright riding position. This is particularly the case for cyclists touring on loaded-to-the-hilt rigs or
simply those riding for long periods of time. Racers and some
sport riders like to have their bars a bit further out because
they prefer a more stretched-out riding position.
For mountain bikes, this guideline may be partially applicable to cross-country riders, but downhillers and freeriders
will want a much shorter cockpit for increased control in
technical situations.
If you're having trouble finding a comfortable position,
one trick is to install an adjustable stem and ride with it for a
while to determine what position works best. This works as
long as the special stem is used on the same frame and with
the components the new stem will be used with — or at least
Handlebars and stems are available with various different clamp-surface
diameters. Make sure you are certain of the size of your handlebar and
stem before changing one or the other.
260
ILLUSTRATED BICYCLE MAINTENANCE
ROAD HANDLEBARS
with a frame of the same geometry and similar components.
Also, when working with an adjustable stem, make changes in
small increments so your body has a chance to get accustomed to each change in order to properly evaluate it. Don't
forget to measure the length you like when you find it, so you
can match up the new stem.
Selecting a Handlebar
PROFILE DESIGNS CARBON X AEROBAR
An aerobar provides an aerodynamic
position for time trials and triathlons
3T XL STEM AND MORPHEUS HANDLEBAR
Ergonomic bends, such as in the
drops of this bar, are said to offer
more comfort on long rides.
DEDA NEWTON PISTA STEM AND PISTA HANDLEBAR
No brakes or shifters are used in track racing,
which means frock-specific bars such as this
one can have a unique curve
MOUNTAIN HANDLEBARS
SALSA S.U.L. STEM AND
PRO MOTO HANDLEBAR
Flat handlebars are still the choice
for mountain bikers seeking the
li ghtest possible parts.
TITEC RIP 3D STEM AND C3 1.0 HANDLEBAR
Riser bars such as this one are currently
a favourite among mountain bikers.
The size of the handlebar, like the stem, should be based on
the physical characteristics of the rider. Road cyclists and
casual riders will want a handlebar about as wide as the distance between their shoulders to provide a position on the
levers that permits unrestricted breathing. Mountain bikers
will want a bar width suited to the terrain and type of riding
that they do. Generally speaking, cross-country riders will
want a handlebar 20 to 80 mm (1 to 3 inches) wider than
their shoulders, and downhillers and freeriders often like their
bars 68 cm (27 inches) or more wide for stability.
In any case, it's important that the reach and height of the
bar allows you to grasp the brake levers without stretching,
and the hooks on a drop bar should offer a position that maximizes the pulling power of your arms and back.
Road Handlebars
Road handlebars once came in a few specific styles that bore
easily recognizable differences between them. Nowadays,
there are seemingly limitless, subtly different styles of road
handlebars. Ranging from ultra-lightweight, one-piece
moulded bar-and-stem combinations made from carbon fibre
to ergonomically shaped road-comfort and touring models,
there is a handlebar made by someone, somewhere to suit
nearly every rider's needs.
Handlebars designed for road racing, sport and touring
riders all share a few common characteristics.The flat top part
of the bar allows an 'upright' position with the hands placed
not quite shoulder-width apart — far enough to allow relaxed
breathing while powering the flats or working up steady,
moderate climbs. A more prone position of the upper body
results when the hands are placed on the brake hoods. This
position is good for a faster effort because the body generates
less wind resistance. It also leaves the chest cavity open for
easy breathing. This position puts the hands at quite a different
angle than the bar-top position. Switching between the two
thus varies the pressure on the hands.
As the hands move to the 'drops' or bottom of the bar, the
upper torso is forced down into a prone or nearly prone position, depending on how the bike is set up. This exposes the
least amount of body area to air resistance and also maximizes
the use of the back muscles for all-out efforts, such as sprints.
The drawback in riding for too long in this position is that
most of the upper-body weight is actually supported by the
palms. This puts pressure on the ulnar nerves and can lead to
HANDLEBARS AND STEMS 261
numb hands, which in some cases may take hours to regain
their full sensitivity.
Regardless of what type of road handlebar you end up
with, it's important that it fits. Most drop handlebars come in
different widths and drops. The width (usually measured
centre to centre across the bottom portion of the bar) should
come close to matching the width of your shoulders. An easy
way to check is to have a friend hold the handlebar against
your back and see if the bar lines up with the centres of your
shoulders. If so, it'll allow you to breathe more normally than
would a narrow bar. A wide bar is also good for those who
climb frequently because it adds leverage. Tandem captains
like wide bars because the leverage adds control.
The drop of the handlebar is how deep the hook sections
are. Usually, riders with larger hands prefer a deeper drop, and
those with smaller hands, a shallower one.
Mountain Bike Handlebars
There are two basic types of handlebars for off-road riding:
flat bars and riser bars.
Flat bars are not perfectly straight; they have a slight bend
ranging from 3 to 9 degrees on each side of the clamping area
for the stem. They are favoured by cross-country racers for
their balance of light weight and rigidity.
While it's arguable that a stronger, lighter handlebar can be
made — and the same position achieved — with a flat bar and
a slightly taller stem, the more popular of the two handlebar
types among off-road riders is by far the riser bar. Riser bars
have a slight upward sweep, ranging from 25 to 60 mm (1 to
1
2 /.
inches), and angle back towards the rider from 6 to 11
degrees on each side.
Upright Handlebars
The tourist bar is available for those riders who desire a permanent upright position. This bar is almost flat or slightly
rising, with ends that turn back towards the rider, and it is
very similar to the handlebars used on the three-speed English racers of years past. This bar essentially offers only one
hand position: on the grips at the ends of the bar. Also, this
bar must be equipped with straight brake levers similar to
those used on mountain bikes.
These three basic types are little more than a sampling of
the many styles of handlebars available. What we have tried to
do in this text is cover the handlebar types of most common
interest to cycling enthusiasts. Rest assured that whatever it is
you seek in a handlebar — whether it is a casual, upright riding
position or a vintage look for a treasured, old bike — it's out
there somewhere.
Installing Handlebars and Stems
Installing a stem and handlebar is pretty simple. Many stems
today come apart, which makes removing and replacing the
bar particularly easy. Unscrew the bolts, separate half of the
bar clamp, and remove and replace the bar.
On stems that don't come apart, it's often helpful to work
the handlebar onto the stem before mounting the stem onto
the bike. This way, you can twist the handlebar in various
directions (and drop bars can take some twisting to install)
without being in danger of hanging them up on the bike.
Flat mountain bike handlebars are usually easy to install.
Loosen the stem binder bolt and push the bar into the clamp
until the bulged middle portion of the stem is centred in the
clamp. Some designs rely on shims between the bar and stem,
which make the job a little trickier: it just gives you one more
thing to centre. If the bar is a tight fit, try gently wedging the
clamp open slightly with a screwdriver as you insert the bar.
(You don't want to bend the clamp.) If your clamp has a bolt
that threads in to tighten the bar, try the coin trick: remove
the bolt, insert a small coin in the binder slot, then screw the
bolt into the threaded part of the clamp so it presses on the
coin. Snugging the bolt will spread the clamp, making installation of the bar easy.
It's also crucial to position a mountain bike handlebar correctly. The ends are angled slightly to correspond with the
way your wrists are angled on your arms. To find the best
position for the handlebar, sit on the bike and rotate the handlebar in the stem until it feels natural to your wrists. Usually,
there's only one position that feels right and if you use
another you'll pay for it with sore wrists.
The most frustrating part of mounting a drop handlebar is
getting the bar stuck inside the stem. There's a trick that'll
eliminate this problem. Look at the clamp — its width narrows
at the bottom near the binder bolt. As you insert the bar, take
your time and keep turning the bar so the tighter inside
radius of the bar is always next to the narrow part of the
clamp as you push the bar through and centre it. When the
bar is centred, snug the binder bolt just enough to keep the
bar from moving.
Once the bar and stem are together, you'll find it easier to
mount them on the bike before attempting to install the
levers and grips or tape the bar. If you're working with a quillstyle stem, exercise some caution here. Before installing the
bar and stem on the bike, determine the length of threading
on the steerer tube to see what the minimum insertion depth
will be. The expander portion of the stem (at its base) must
extend beyond this depth, or the chance of deforming or
even splitting the steerer tube will greatly increase because of
the thinner wall thickness at the threads. However, in no case
should there be less than 5 cm (2 inches) of the stem inside
the fork. Most quill-style stem makers are now marking the
minimum-insertion point on their stems so you'll know
when it's inserted enough.
Before inserting a quill-style stem into the steerer tube,
smear a generous coat of grease over the inserted portion to
262 ILLUSTRATED BICYCLE MAINTENANCE
keep the dissimilar metals from corroding together and to
provide a grease seal against moisture. Lower the stem to
where you think you'll want it (keeping in mind the safe
limit), and tighten the bolt.
If you perspire heavily while riding or if you frequently
ride in the rain, moisture may work its way down inside your
head tube. One way to cope with the problem is to replace
the locknut on your headset with a locknut that has an
0-ring seal built into it. This will minimize the possibility of
corrosion developing, which, if left unchecked, will actually
weld the stem to the steering tube.
You're less likely to have problems with threadless-style
stems. They can get stuck on the fork, but usually they come
off with a little twisting and tugging. They're easy to put on,
too, because they just slip over the top of the fork and then
you tighten the clamping bolts. The only tricky part is that
threadless-style stems are part of the headset (the steering
bearings) system, so when installing and removing them, you
must deal with headset adjustment.
This means working with the top cap, the cap that sits on
top of the stem. Seat the stem on the fork, then put on the
top cap and screw in the top bolt. Tightening the top bolt is
how you adjust the headset. Snug the bolt until the headset
has no play. Then you can centre the stem and tighten the
clamping bolts to fix it in place.
Bar-ends. Some people like to add bar-ends to flat and
riser handlebars. These add-ons provide another hand position, which can help eliminate some of the discomfort on jarring rides. They're handy on technical climbs, too, because
they allow a rider to shift body positions to increase traction.
It's important to install bar-ends correctly, however. Use
care not to scratch or pinch the end of the handlebar when
installing the bar-ends because this can lead to a broken handlebar. Tighten them just enough so that they support your
weight and cannot move. Position the bar-ends so they feel
like natural extensions of your wrists when you're comfortably sitting on the seat. If you feel any discomfort or pressure
on your wrists while riding, the bar-ends are probably set at
the wrong angle; readjust them. Carry the necesssary tool on
the first few rides and you can easily dial them in.
Finally, when you're riding on a bike with bar-ends, don't
make the mistake of using them all the time. It takes more
time to get to the brakes when you're on your bar-ends.
Reserve them for safe stretches and stay off them on treacherous descents.
Padding the Bars
Many people find that after riding bicycles for long periods
of time, they begin to experience numbness in their hands.
This is a problem that should not be ignored because it can
develop into a serious and chronic condition. One easy way
to minimize the problem is to wear padded gloves. Another
way is to place some kind of padding on the handlebar itself.
Check to see if the adjustment of your seat, stem and/or bar
is contributing to the problem by either allowing an excessive
amount of your weight to rest on the bar or placing your
wrists in a strained position.
For adding cushion to a flat bar, experiment with different
grip types and shapes.
For drop handlebars, there are a number of shockabsorbing handlebar wraps and pads on the market today. One
of the most popular, Specialized Bar Phat, includes silicongel-filled packets in different thicknesses. The packets adhere
to the top section and to the drops of road handlebars and are
then wrapped over. Another favourite is Cinelli Gel wrap. By
splicing a layer of gel material to a layer of Cinelli's natural
cork wrap, they've been able to create a more comfortable
wrap that doesn't increase the overall diameter of the grip.
This is welcome news to riders with small hands as well as
racers who want increased comfort but can't risk using a thick
grip that could rob power in the sprint.
Taping Drop Handlebars
There are two ways that handlebar tape can be wrapped: from
the top down, or from the bottom up. Each method has its
advantages and disadvantages. The advantage in wrapping
from the top down is that the end where you begin can be
neatly wrapped over itself, and the other end can be tucked
into the end of the bar and sealed with a plug. Thus there are
no loose ends to unravel.The disadvantage is that the overlaps
face upward on the bends. With time and use, pressure from
the hands has a tendency to peel or roll the tape back.
This problem can be avoided by wrapping the tape from
the bottom up.A little tape is left at the beginning to tuck into
the bar-end, then that end is secured with a plug. However, the
finishing end at the stem sleeve has to be secured in some way
to prevent unravelling. The accepted technique is to wrap a
piece of electrician's tape or coloured plastic stretch tape
around that end. Electrician's tape has a good deal of elasticity
in it, so as you wrap it around the bar, pull it taut. When you
let go, it will shrink back into a tight bond around the handlebar tape.
Whichever taping method you choose, before beginning
to actually wind tape around the bar, cut a short piece of tape
from each roll, just long enough to cover one of the brake
lever clamp bands on the side of the bar that you are about to
wrap. Don't cut off more than you need so you don't run
short of tape. Also, check the package; the manufacturer may
have included the short pieces.
As you wrap, try to overlap about one-half the width of the
tape, if possible. When you reach curved sections of the bar,
you will have to use more overlap on the inside curves and
less on the outside. How much you can overlap depends on
the length of tape provided. Unfortunately, you can deter-
HANDLEBARS AND STEMS 263
mine the proper overlap only by trial and error. If you get to
the end of the tape before you've wrapped the whole bar, just
unwind the tape and try again. Also, don't forget to maintain
some tension on the tape to stretch it a bit as you wrap. This
will make for a smooth, snug fit and will help you get enough
length out of the tape to cover the bar.
When you reach a lever, hold a cut-off piece of tape over
the clamp band while you make a figure-of-eight loop
around the lever hood and the bar, along with an additional
loop around the lever hood. This will secure the short piece
of tape and hide the clamp band. When the tape wrapping is
complete, don't forget to plug the ends of the bar. Even if you
don't need plugs to secure the tape, push them in place; if you
crash and fall on open bar-ends, you can get badly hurt.
they're all the way on. The alcohol will evaporate quickly, so
act fast. Some mechanics recommend hair spray, which works
in a similar fashion by lubricating the grips initially and then
evaporating so that the grips will stick.
A trick that we've found helpful, especially in very wet
conditions, is wiring on the grips. Mountain bike racers often
encounter muddy conditions that can cause the grips to
loosen on the handlebar. When a grip comes loose, the rider
can have trouble controlling the bike. Wrap a small-gauge
wire around the grip in two places, then wind the ends to
constrict the wire and secure the grips in place. To finish the
job, cut the wire and press the end into the grip so it can't
scratch you. This treatment ensures that the grip won't come
loose no matter how much muck you ride in.
Installing Mountain Bike Grips
Adjusting the Bar and Stem
While they look simple, mountain bike grips can be challenging. They're designed not to slip around, because that
would make it difficult to hang on to the handlebar. Unfortunately, this can make them tough to remove and install. If
the grips are worn out, the easiest way to remove them is to
carefully cut them off with a utility knife. If you plan to reuse
the grips, try lifting them by sliding a thin-blade screwdriver
underneath and squirting in alcohol. If you get enough under
the grips, you'll be able to work them off. Don't use oil,
which will make the grips permanently slippery.
To install new grips, make sure the handlebar is clean of any
oil or grease, which may make the grips slip. Coat the inside
of the grips with alcohol and slide them in place, making sure
The height of your stern and handlebar cannot be properly set
until the saddle has been adjusted to its appropriate height and
angle. Once that's taken care of, check the height of the bar in
relation to the saddle. For general-purpose riding, the bar
should ideally be about 2 to 3 cm (1 inch) lower than the
saddle. Another way of checking both the bar height and the
stem length is to sit in the saddle and place your hands just
behind the brake lever hoods (on a road bike) or grab the grips
(on a mountain bike). When you straighten both your arms
and your back, your back should be at a 45-degree angle in
relation to the ground.
Here again, the rule may vary somewhat for specialized
riding needs. Cyclists who expect to ride primarily in an
A dropped handlebar gives the rider a lower, more aerodynamic
A flat bar results in a more upright position, which gives the rider better
position on the bike.
control in technical off-road situations.
264 ILLUSTRATED BICYCLE MAINTENANCE
upright position may wish to set the bar at approximately the
same height as or even slightly higher than the saddle; those
who wish to do a lot of fast riding in a low, aerodynamic position may wish to drop the bars a couple of inches below the
saddle.The 2 to 3-cm rule should be taken as a starting place
from which to find the height that suits your particular needs.
To experiment with different bar and stem heights, try each
one for a week or two and make changes in increments of no
more than 5 mm each time. This will make it easier for your
body to adjust and thus give each setting a fair try.
Keep in mind that threadless-style stems don't usually have
a lot of height adjustment. Sometimes there are spacers that
can be flip-flopped from beneath the stem to above it, or
vice-versa, to dial in position. If not, you can get a higher-rise
stem or a new bar that corrects your position.
After the stem height has been set, the last adjustment to
be made is the handlebar position. For drop road bars, many
riders like the flat portion at the ends of the bars to be parallel to the top tube. Others like it with the hooks pushed forward a bit so the ends slope slightly downward. One
suggested rule is to set the bar so that the slope of its ends follows an imaginary line that bisects the seatstays.The argument
is that this position places the wrists in the most natural and
comfortable position when the hands are on the drops.
For a flat mountain bike handlebar, adjust the angle so that
you can hold the bar comfortably without any wrist strain.
Because the bar angle is easily adjustable, experiment with
various settings if you'd like. If you want to change your position, do it a little at a time. Let your body get used to
each increment of change before moving the position again.
Otherwise, you may struggle to adapt to the change.
Since your hands provide approximately one-third of the
contact that occurs between your body and your bicycle and
perform about 90 percent of the control work, it's worth
spending some time and effort in finding the most comfortable and efficient handlebar position. An unsuitable riding
position irritates the nerves in the hands and arms and strains
the back. That, in turn, leads to numb hands and sore neck,
shoulder and back muscles. Nothing is more likely to take the
pleasure out of riding a bike. A little time spent finding the
right equipment and adjusting it to the optimum position
will be more than repaid in riding enjoyment.
TROUBLESHOOTING
PROBLEM: You hear constant clicking when you climb
out of the saddle.
Loosen the handlebar binder bolt, move the bar
over enough to grease the centre section of the bar, grease it,
push the bar back in place and tighten the bolt.
SOLUTION:
PROBLEM: You've loosened the quill-style stem and
tapped the bolt. The bolt is now slightly loose and the
stem turns, but when you pull on the bar, the stem will
not come out of the frame.
The wedge at the base of the stem (inside the
fork) has probably got stuck inside. Unscrew the bolt completely and lift the stem out of the fork. Then carefully
thread the bolt back into the wedge, which you'll be able to
see down in the fork. Wiggle the stem bolt to work the
wedge out and reassemble the stem.
SOLUTION:
PROBLEM: Your
hands get numb while riding.
SOLUTION: Try
thicker, softer or differently shaped grips.
On a dropped bar, add padding to the bar tape. Wear padded
gloves. Move your hands every few minutes while riding.
Make sure the stem and bar position doesn't put too much
of your weight on the handlebar.
PROBLEM: You've tightened the quill-style stem bolt a
lot, but the stem isn't tight enough. It turns when you
twist the handlebar.
SOLUTION: Remove the stem and make sure that the
wedge in its base is seated correctly. Sometimes the wedge
gets cocked off to one side during installation, and tightening
it won't secure the stem. Reposition the wedge so it'll jam
the stem in place, and retighten the bolt. Still not tight?
Make sure that there is only a trace of grease on the stem.
PROBLEM: The stem has corroded inside the fork and
will not come out.
Apply some penetrating solvent. Clamp the fork
crown in a vice (use wood blocks to protect the crown), and
twist the bar from side to side to break the bond. No? Heat
the stem with a propane torch — but work in a well-ventilated area and be careful not to touch the heated zones.
SOLUTION:
PROBLEM: You tighten the handlebar-clamping bolt but
the drop bar won't get tight in the stem, and when you
hit the brakes hard, they change position.
The bar diameter and the handlebar-clamping
diameter of the stem must match. If they do not, get parts
that fit. If they do, slide the bar out of the clamp, sand the bar
centre section just enough to rough it up, reinstall it and
tighten the bolt.
SOLUTION:
HANDLEBARS AND STEMS 265
Handlebar and Stem Adjustment
In a bike crash, the handlebar often gets twisted out of line. This may
even occur as the result of a strong tug on the bar after hitting a rut.
Whatever the cause, correct any misalignment of the bar as soon
as possible, and then tighten the stem sufficiently to minimize the possibility
of it occurring again.
Before you can make a lateral adjustment in the handlebar, loosen the stem.
On quill-type stems, turn the stem expander bolt anticlockwise a turn or two.
On threadless stems, loosen the clamping bolt(s) on the side. Hold the front
wheel of the bike between your knees, and twist the bar sideways until the
stem is properly aligned with the wheel. Retighten the bolt(s) (see photo).
When tightening a quill-style stem expander bolt that has an hex fitting, make
it as tight as you can get it with the leverage provided by the small tool. If the
bolt head can be turned by a large adjustable spanner, do not try to tighten it
as far as possible because you might end up cracking the steerer tube.
One way to test the stem for adequate tightness is to hold the front
wheel between your knees and give the bar a vigorous twist. You
should not be able to easily move it back out of line.
To adjust the handlebar height, loosen the stem expander bolt. If the stem has
not been moved for some time, you may find the expander wedge (quill-style
stem only) does not drop down with the loosening of the bolt. In this case, give
the head of the bolt a sharp rap with a plastic mallet. If you lack that particular tool, hold a small block of wood on top of the bolt to cushion the shock,
and hit it with a hammer (see photo).
266
ILLUSTRATED BICYCLE MAINTENANCE
3
When setting the handlebar height, make certain that at least 5 cm
(2 inches) of a quill-style stem extend down into the steerer tube.
Many manufacturers mark their stems with a minimum insertion line
(see photo). Make sure that the stem is in far enough to cover this line.
4
Some people like to set their handlebar with the lower part of the
drops parallel to the top tube. Others prefer to set them along an
imaginary line that runs from the bar back to the midpoint between
the saddle and the rear axle. You should set them at least somewhere within
this range. To adjust the angle of the bar, loosen the binder bolt on the clamp
(see photo). Rotate the bar into the desired position and retighten the bolt.
HANDLEBARS AND STEMS 267
Before you can remove a handlebar from the stem, you must ship
off the handlebar tape and unclamp and slide off the brake levers.
Then you can loosen the binder bolt and work the bar out of the stem.
When installing or removing bars, when you reach a bend, the bar will
become difficult to move (see photo). To make it easier, rotate the bar so that
its inside radius stays next to the narrowest part of the clamp. You may find
you have more room to manoeuvre if you mount the bar on the stem with the
stem off the bike.
6
Before installing a new stem or reinstalling an old one, give the part
of the stem that will be inserted into the steerer tube a good coating
of grease. That will make it easier to get the stem out later and will
prevent moisture from seeping down inside.
ILLUSTRATED RICYCIF AAAINTFNARICF
Removing and Installing Road Stem
and Bar for Threadless Headset
1
To remove the stem, loosen the hex bolt in the cap on top of the stem
by turning it anticlockwise (see photo), then remove the bolt. Lift off the
top cap (if it's stuck, it will come off when you remove the stem).
Use a hex key to loosen the hex bolt(s) in the stem's side.
Remove the stem, being sure to hold the fork from below because the
stem was what was holding it in the frame (see photo). If the stem is
stuck, tap the bolt(s), apply a little lube on top, clamp the wheel
between your knees, grab the bar, and twist to free and remove the stem.
HANDLEBARS AND STEMS 269
4
To get a bar through the clamp easily, try this trick: remove the stem
bolt and place a small coin between the 'ears' that the bolt goes into.
Place the bolt in the lower hole and thread it until it strikes the coin
(see photo). By tightening the bolt, you'll gradually open the clamp, making
bar installation much easier. Don't overdo it: if you tighten too much, you'll
permanently deform the clamp, and you won't be able to put the bolt back in.
Remember to work the bar through the clamp in the correct direction
so that it doesn't end up upside down.
Reinstall the binder bolt and turn it clockwise to securely tighten the
bar (see photo). Check the bar's tightness by pulling on the drops. Did
they move? If so, loosen the bolt, reset the bar in the correct position,
and retighten until it can't move.
Reinstall the stem and top cap and the hex bolt. Turn the bolt clockwise to
seat it in the cap. This also adjusts the headset bearings. Hold the fork with
one hand and the frame with the other, and push and pull to feel for play.
Keep tightening the top bolt until there's no play in the headset and the fork
turns smoothly from side to side. When the adjustment feels right, centre the
stem and tighten the hex bolt(s) on the stem's side.
270
ILLUSTRATED BICYCLE MAINTENANCE
Taping a Handlebar
1
Handlebar tape is both practical and decorative. It enables a handlebar to be gripped more firmly and more comfortably than if it
remained bare metal.
Even if the handlebar is never removed, from time to time it can use retaping.
After a while, any tape will become worn and dirty. New tape is an inexpensive way to recondition a bike.
Before applying new tape, clean off any remaining residue from the old tape.
Also, use this opportunity to check the location and tightness of the brake
levers. The bolt for loosening and tightening these clamps is located either
inside the body of the lever or beneath the rubber hood.
2
If the new tape didn't come with precut pieces, cut a piece of tape off
the end of each roll that's just long enough to fit over the visible part
of the brake lever clamp (see photo 4). Set it aside until your wrap-
ping reaches that point. You can wrap two ways: top to bottom, or bottom to
top. We recommend the latter because the tape is less likely to unravel.
3
Start wrapping the handlebar at the end and work your way up to
the stem area. Tape the end of the tape onto the end of the bar so
that about two-thirds of the width of the first tape wrap overlaps the
bar-end. Tuck the tape in, and push in the handlebar plug to keep the tape in
place (see photo).
Overlap the beginning end completely, then continue along the straight
section of the bar, overlapping between one-third and one-half the width of
the tape. Keep tension on the tape as you wrap to make it stretch a little bit.
HANDLEBARS AND STEMS 271
4
For a neat job at the lever clamp, wrap the short piece of tape around
it and hold the piece there while covering it with a figure-of-eight
pattern of the tape (see photo). At the ends of the figure-of-eight,
continue the regular taping pattern along the bar.
When wrapping the curved parts of the bar, use slightly more tape
overlap on the inside of the curves and less on the outside.
C
When you reach the top of the bar, there should be enough tape left
to go around the bar once. If you have a lot left over, cut it off after
checking that you didn't leave any gaps in your wrap job (if you did,
unwrap and try again). Finish the job by wrapping electrical tape around the
bar tape to keep it in place (see photo). If you wrapped from top to bottom,
fold over the final loop of tape, and push it into the end of the bar along with
any tape remaining on the roll. Secure the tape by pressing the plugs into the
ends of the bar. If you did not have enough tape to complete the job, you
overlapped more than you should have. Unwrap most or all of the tape and
try again. Stretch the tape more this time so it'll go further.
272
ILLUSTRATED BICYCLE MAINTENANCE
Installing Mountain Bike Stem
and Grips
a
1
There are two types of mountain bike stem. The most common is the
threadless style, but there are also quill-style stems that are similar in
design to most road stems. The latter type attaches by inserting it into
the fork and tightening the hex bolt, which pulls up a wedge that tightens the
base of the stem inside the fork. Before installing a new quill-style stem, coat
the lower portion with grease to prevent corrosion.
To either remove or adjust the stem, you usually have to loosen the
hex bolt and strike it with a plastic mallet to knock down the wedge
2 inside, which will free the stem.
3
The threadless-style stem slides over a fork with a threadless steerer
and clamps in place. On this system, the stem is an integral part of the
steering's bearing mechanism, acting as the main locking mechanism.
To install a threadless-style stem, slide it over the fork (see photo) and install
the top cap of the headset. Thread in the hex bolt and tighten it — this adjusts
the headset — and tighten the clamping bolts of the stem. If you've done it
right, there will be no play in the steering bearings, and the stem will be tight
and centred.
HANDLEBARS AND STEMS 273
Usually, it's easy to install a mountain bike handlebar because there
are no curves in the bar to deal with. If yours is a tight fit, however,
try this: remove the binder bolt and use a screwdriver to wedge the
clamp open slightly while inserting the bar (see photo). Don't overdo it, or
you'll bend the clamp, which can make it difficult to get the bolt back in.
Another way to make it easier to insert the bar in the clamp is to try
the coin trick: remove the binder bolt and insert a small coin between
the two holes that the bolt goes through. Place the bolt in the lower
hole, and screw it until it presses on the coin. Snugging the bolt will spread the
clamp, making bar installation easy (see photo).
7.11111Mr
-
1.1■
11■
6
When the handlebar and the shift and brake levers are in place,
finish the job by installing the grips. Clean the bar with a solvent such
as alcohol because any residual oil or grease can make the grips slip.
New grips do fit snugly, so to make things easier, pour a small amount of
alcohol into each before sliding it onto the bar. The alcohol will make the
grips slippery at first but will then evaporate, so the grips will hold fast.
To remove old grips, carefully cut them off with a sharp knife. If you wish
to reuse them, lift the edges with a thin-bladed screwdriver and drip some
alcohol underneath the grips (see photo). If you get enough between the
grips and handlebar, you should be able to slide the grips off fairly easily.
CHAPTER 15
Saddles and
Seatposts
There are three places on every bike where the rider and The shell can be made of steel, leather, or plastic. Steel shells are
bicycle meet. Feet on pedals provide drive, hands on handlebar sometimes found on inexpensive bicycles.The steel shell is covered with a piece oflow-density foam covered in vinyl.Though
lend guidance and your backside on the seat...
The seat on a bicycle is more properly called a saddle. these saddles may feel soft, they aren't very comfortable. The
Though it sounds like a simple argument of semantics, it's not. foam compresses easily, and you end up sitting on a plate of steel
A saddle serves multiple purposes. Most obviously, it supports that doesn't conform to your body.
Saddles that feature a piece of thick leather mounted over
the greatest portion of your body weight while you are seated
on the bike, but it also positions you correctly over the pedals a metal frame are probably the oldest style still available. Given
for greatest efficiency and acts as an important control surface adequate time for a proper break-in, the leather top will
that lets you use your entire body weight in steering. A seat is become soft and resilient and will conform to the particular
anatomy of the person using it. At one
little more than a place to park your
WTB Laser V time, leather saddles of this type came
buttocks.That thing in front of your TV Specialized Dolce
women's specific saddle
Team saddle in all price ranges but these days are
is a seat. Atop your bicycle is a saddle.
found only in the upper price ranges.
As a cyclist, the most intimate relaThis type of leather saddle requires
tionship that forms between you and
special care. Carry along a plastic bag
any part of your bicycle is with your
to protect it from the rain in case you
saddle. This is probably the principal
get caught in a storm. Leather saddles
reason that it's the prime source of
like this also need some breaking in
complaints about pain on a bike. Often
before they're really comfortable and
the reason a saddle is uncomfortable is
conform well to your hind side. You
because it's improperly adjusted or
can help this process along by applying
simply not well matched to the cyclist's
anatomy. Bicycle saddles are not all Cutaway saddles such as these are intended to reduce some type of leather dressing.
Padded saddles with vinyl bases and
alike; there's an amazing diversity to be pressure in a sensitive area and eliminate postride
vinyl, leather and artificial-leather tops
found both in design and construction numbness and other longer-term health risks.
are probably the most popular today.
materials. Somewhere in all this diverSome consist of nothing more than a top shaped much like the
sity should be a saddle that's right for you.
The most important rule to remember about conventional basic leather saddle. More exotic models have shells that vary
saddles is that everybody's posterior is different, and what is in thickness to allow for different levels of softness or hardness
comfortable for one person may be torture for another. Not at different points.These saddles use special high-density foams
only that, but a saddle that is well suited to short, fast, racing for padding and feature 'bumps' that put a little extra padding
events may be ill-suited to long-distance touring. Proper under the pelvic contact points. Saddles with these bumps are
saddle selection must take into account both anatomy and generally called anatomic saddles, and the tops are usually vinyl
riding needs. In short, saddles are a very personal thing, so no or leather.
The rails and frame are the structures that support the shell
matter what anyone else says about a particular model, you
and connect it to the seatpost. Normally, the rails are made of
have to make the final decision.
steel, although aluminium and titanium are used as well. Generally, steel is the best choice for bigger riders or for hard use.
Basic Saddle Construction
The bicycle saddle consists of a shell, which is the part you sit Titanium rails can flex slightly, offering a little shock relief,
and they're usually found on the lightest saddles.
on, and a carriage or frame, the part that supports the shell.
276 ILLUSTRATED BICYCLE MAINTENANCE
SADDLE RAILS
SADDLE CLAMP
SADDLES AND SEATPOSTS 277
The saddle's nose is supported by one end of the frame
and the tail of the saddle is supported by the other. Connecting the two are the saddle rails. These two rails also link
the saddle to the seatpost.
Saddles
Generally, there are three basic kinds of saddles: cruiser, comfort and racing. The cruiser saddle is quite wide, sometimes
includes springs and is heavily padded. Like the cruiser saddle,
comfort saddles are designed with comfort in mind, as the
name implies, but also are intended to allow easy pedalling.
There are many variations. Racing saddles consider comfort
from a slightly different perspective. Firm support and a trim
exterior minimize chafing and excessive movement while
pedalling at high cadence for long periods of time.
Cruiser saddles. Cruiser saddles are designed to provide lots
of cushioning for cyclists who sit in the bolt-upright cruiser
position, which puts a lot of weight on the saddle. They're
wider, so they're not as practical if you're trying to pedal
quickly, but for spinning casually around the neighbourhood,
they're quite adequate.
Comfort saddles. Comfort saddles range widely in design to
suit cyclists from those looking for a cushy ride around the
block to long-distance tourists covering great distances,
spending hours on end in the saddle. Most have extra
padding to help cushion the shock of rough country roads
and unpaved trails. The extra padding is usually placed under
the ischia, the pelvic bones that press into the saddle when
you're sitting down. The ischia, sometimes called the sit
bones, bear the weight of your upper body.You can see this
extra padding on the saddle in the form of bumps. Some saddles don't appear to have bumps, but the extra padding is
there; it's just that the bumps go down instead of up. The
extra padding weighs a bit more, so many racers forgo it.
Oddly enough, what have proven over the years to be the
favoured saddles of long-distance tourists and cycling purists
appear at first glance to be the most uncomfortable saddle
you could imagine. Hard leather saddles like those made by
Brooks can take many hundreds of kilometres to break in
properly, but in that time they take on a moulded shape that
closely matches the rider's hindquarters. Though those first
800 km (500 miles) might be torturous, the result is a saddle
formed to your shape that, properly cared for, can carry you
in comfort for decades.
Racing saddles. Racing saddles are built to allow full
movement of the legs with a minimal amount of chafing.
These design goals lead to some interesting and unusuallooking shapes. Thanks to careful development over the
years, it is now possible to find a racing saddle that provides
an efficient platform for pedalling while at the same time
reduces the fatigue and numbness once equated with slender
saddles.
Because women have wider hips than men, they also have
wider ischial bones.This means that when they sit on a men's
saddle, the ischial bones are not supported by the saddle. This
can be quite uncomfortable. Women's saddles are designed
with slightly wider tails to ensure proper pelvic support. The
anatomic women's saddle also has material relieved or
entirely cut away just behind the nose for increased riding
comfort. Keep in mind that not all women find women's
saddles comfortable. Some women feel best on other types.
The most recent development in saddle design goes by many
names. Comfort groove, cutaway, soft centre and channelled
saddles are all essentially the same thing. By creating a void or
soft spot in the centre portion of the saddle, pressure is relieved
from the area of soft tissue associated with reproduction.
Supporting evidence connecting long-term health
concerns with saddle time has been shown in recent years to
have some gaps. If Eddy Merckx could sire a son... well, you
get the picture. Still, 'better safe than sorry' would seem to
apply here, so millions of cutaway saddles have been sold
since their introduction just a few short years ago.
For people who can't seem to get comfortable even on
cutaway saddles, the inventors of the world have been busy
dreaming up some bizarre interpretations of the bicycle
saddle — using the term 'saddle' very loosely. There are inflatable saddles, ones with independent cushions (one for each
cheek) and saddles so bizarrely shaped that you might
wonder if you could actually sit on them.
If you're basically satisfied with the shape of your bicycle
saddle but would appreciate a little additional padding, you
might wish to try a gel or foam saddle cover. There are also
covers on the market that employ air or water to create a
cushion between you and your saddle. Some people even use
sheepskin saddle covers. These help prevent saddle chafing,
but they don't add much padding.
Selecting a Saddle
When you decide to purchase a new saddle, be sure you're
buying what works for you. Don't worry about what everybody else is riding.You have to find something that agrees with
your anatomy and riding style. For example, if you're a man
with wide hips, don't pick a skinny racing saddle just to be in
style. If a wider saddle, such as one designed for a woman, fits
your body, don't hesitate to give it a try.
Most important, don't stubbornly keep riding on a saddle
if it is numbing your crotch or causing other pain. If you've
just started riding, you may be getting used to sitting on a
saddle, and the break-in period can take a few rides, but the
pain should go away as you get used to the saddle. If not, try
a few different saddles.
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Wearing cycling shorts can make a major difference in
comfort, too. Ordinary gym shorts and exercise clothing have
seams in the crotch area, which cause chafing and can pinch
blood vessels leading to numbness and discomfort. Cycling
shorts, which come in all manner of styles these days (not just
skin-tight nylon), have a padded and seamless crotch. Riding
in a good pair is surprisingly comfortable.
Seatposts
The seatpost attaches your saddle to the bicycle. It also allows
you to adjust the height and the fore and aft position of the
saddle on the bike.
A bicycle seatpost consists of a pillar and a clamp. Sometimes these parts are integrated into one unit, in which case
they are referred to as a one-piece seatpost.The two-part seatpost consists of a tube with a clamp attached around its upper
end. The clamp simultaneously holds the rails of the saddle in
the chosen position and fastens the saddle to the top of the
seatpost. On this type of seatpost, the clamp is usually made of
steel and has serrations that allow the saddle to be tilted up or
down and set at various angles. These serrations are rather
coarse in order to support a cyclist's weight, and they don't
allow fine adjustments.The pillar part of the seatpost on which
this clamp fastens may be made of either steel or aluminium.
A one-piece seatpost is more rigid than a two-piece model
because the clamp is integrated into the upper end of the
post. This gives the rider a better base to push against and
thus is more efficient. On the most basic level, the clamp
assembly on this type of post is the same as that in a two-piece
system, in that it controls tilt as well as the fore-and-aft position of the saddle.
The cheapest one-piece seatposts are also similar to the
two-piece models in that they employ a clamp with serrations, which allows only finite adjustments, and a bolt running
through the side of the clamp. This type of one-bolt system is
easy to use and quite reliable.
As you move up in quality, you can find one-piece seatposts that employ a single bolt that runs vertically through the
clamp. Shimano manufactures several posts of this type, which
make use of a set screw instead of serrations to set the tilt.
These posts are thus infinitely, or 'micro', adjustable.
The double-bolt micro-adjusting seatpost has the best adjustment system available. Two bolts pull in opposition to each
other, which allows you to make very small changes to the angle
of the seatpost.This system prevents the angle of the saddle from
changing unless a bolt breaks or the saddle rails bend.
Saddle Tilt
Often the discomfort that people feel when riding is not the
fault of the saddle design, but simply a matter of improper
adjustment. If, for example, the nose of the saddle is tilted
down, the cyclist's body weight is thrown forward, creating
extra strain on the arms and shoulders. On the other hand, if
the nose of the saddle is tilted up, the cyclist may feel discomfort in the genital area. This is particularly true for the
male cyclist, and it is especially likely to occur when he rides
with his hands on the dropped parts of the handlebar.
As a general rule, your bicycle saddle should be set parallel
to the ground. If the top of your saddle is sloped or curved,
simply lay a straight edge (a ruler will work) along the top of
your saddle, from the nose to the back, and use that as your
line of reference.
If your seatpost has a standard clamp or is a single-bolt onepiece design, loosen the clamp, move the saddle so that it's parallel to the ground, then retighten the clamp. On two-bolt
designs, loosen the bolt on the end that you want to go up and
tighten the bolt on the end that you want to go down.
Some bikes, usually less-expensive models, have saddles
that are attached by a clamp to a basic tube-style seatpost
(there's no built-in hardware for holding the saddle). These
clamps are prone to slipping, which causes the saddle to
change angles when you're riding. If a saddle has been rocking
like this and changing angles for a while, the clamp is probably worn out and should be replaced.Take the saddle or bike
to a shop so they can find the correct clamp. There are two
sizes, Vs and /8 inch, the latter being more common.
When you work on the clamp, you'll notice the serrations
that allow the clamp to hold its position when it's tightened.
When these grooves wear, however, the saddle can slip. It's
important when installing a clamp-style saddle to level it and
then tighten the clamp securely. First loosen the nut(s) and
apply oil to the threads on the bolt that passes through the
clamp. Make sure that the seatpost is all the way through the
clamp and protruding from the top of the clamp (otherwise
the clamp won't tighten adequately).Tighten the clamp when
you're 'sure you have the saddle at the angle you want. If the
clamp has two nuts, tighten them evenly until the saddle can't
be turned sideways or rocked.
Saddle Height
Proper saddle height is very important. If the saddle is too low,
riding becomes very difficult. If it's too high, you can't get the
leverage that you need on the cranks for efficient pedalling.
Improper height in either direction can lead to injury: when the
saddle is too low, excessive stress is placed on the knees; when it's
too high, your hips tend to rock, causing you to rub excessively
against the saddle and possibly creating saddle sores.
The correct saddle height makes riding both comfortable
and efficient. To find the correct saddle height, sit on the
bicycle with both feet on the pedals. Hold yourself up, by
hanging onto a wall, asking a friend to help, or putting your
bike on a trainer (make sure that the bike is parallel to the
ground). Pedal backwards until one pedal is in the 6-o'clock
position and the other pedal is in the 12-o'clock position.
SADDLES AND SEATPOSTS 279
Place your heel on the lower pedal. In this position, your
leg should be fully extended. If your knee is bent, raise the
saddle. If your hips must rock to allow you to reach the pedal
or if your leg won't reach it, lower the saddle. When you spin
the cranks and your foot is properly positioned on the pedal,
your leg will be almost, but not completely, extended.
To adjust the height of the saddle, loosen the seatpost
binder bolt on the seat tube, move the saddle up or down to
the desired position, then retighten. Most bicycles require an
hex key or some other type of spanner to loosen the seatpost
binder bolt. However, some bicycles, primarily mountain
bikes, use quick-release seatpost bolts. Such bolts allow you to
adjust the saddle height without tools. This is useful for
mountain bikers who like to lower their saddles when
descending steep terrain. For road use, they aren't very useful
because the terrain is fairly constant. They also make your
saddle an easy target for thieves.
After using the recommended technique to set your saddle
height, try it out. If your feet are long and you tend to point
your toes down while pedalling, you may find that your
saddle now feels too low. Don't raise it right away — your
body may simply need to readjust to the correct pedalling
position. Try it for a few rides and see if your riding comfort
and efficiency improve.
Once you have your saddle at the proper height, reassess
the saddle angle. Normally, parallel to the ground is best. But
ride your bike for a while to see how it feels. Then move the
nose up or down a little, if necessary, to get it to the position
that's most comfortable for you.
RockShox suspension seatpost
USE Shokpost SX
Suspension seatposts have gained in popularity by leaps and bounds in
recent years. What was once a tool of mountain bikers looking to soften the
ride of their racing hardtails has been discovered by road riders, tourists and
casual cyclists as a great way to smooth out rough roads. The road-type
seatpost (left) provides 35 mm (1 1,4 inches) of cushioning. The mountain-bikefriendly seatpost (right) gives 51mm (2 inches) of travel.
saddle drastically changes their outlooks on cycling. With
such a wide range of saddle designs from which to choose,
there's really no reason for any cyclist to experience persistent
discomfort while riding a bike.
Saddle Position
The correct fore-and-aft saddle position allows you to get the
maximum leverage from your muscles. Too far forwards and
you sacrifice leverage; too far back and you experience back
strain.As with height and tilt, this is an adjustment worth getting right.
To find the correct position, you will once again have to
sit on the bike with both feet on the pedals and have someone
or something hold you up. This time, backpedal until the
pedals are at the 3- and 9-o'clock positions.
Tie a weight (a large nut or a small spanner will work fine)
to the end of a string and hang it next to your knee on your
forward leg. Hold the string against the notch in the side of
your kneecap. The string should pass through the centre of
the pedal axle. If the string is behind the pedal, loosen the
clamp and move the saddle forward. If it's in front of the pedal
axle, move the saddle back. After completing this fore-and-aft
adjustment, check again to make sure that the saddle has the
right tilt.
If you've put a lot of miles on your bike after making all
the proper adjustments but you still find your saddle uncomfortable, try a new one. Many riders find that a change of
Suspension Seatposts
Although it's no cure for a bad saddle, one way to improve
comfort is a suspension seatpost.There are many models, from
telescoping-post to linkage designs, from short travel to long
travel, from posts with springs inside to those that rely on
rubber shocks.
These posts are awesome for turning a hardtail mountain
bike into a better, more comfortable machine for riding on
harsh or technical trails. They're also great for taking the bite
out of rough pavement, and many century riders and commuters swear by the posts.
Suspension posts add a little weight compared to ordinary
models, and they usually can't be set as low in the frame due
to interference by the mechanism that's often built into the
top of the post. They really are nice if you'd like to sweeten
the ride of your bike a bit, though.
When you buy a shock post, be sure to read the owner's
manual for tips on adjusting it to your weight. There's usually
a way to set the preload, either by adjusting part of the post
or by changing the rubber bumpers in the post, and the
owner's manual will explain this.
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Setting the saddle height is a little different with a suspension post. Because it will sink slightly when your weight is on
it, it must be set slightly high. The best way to find the right
height is to ride a bit. Take along a hex key, if necessary, and
adjust the post until it feels right when you're spinning along.
You want it to absorb the hits, but you also want it to support
your body in the right position. If it's too high or too low, you
risk injuring your knees the same way that you would by
riding a wrongly positioned rigid post. Be sure to spend some
time getting it right.
TROUBLESHOOTING
PROBLEM: You try to raise or lower the seatpost but
discover that it won't budge, no matter how you yank,
twist and tug.
SOLUTION: Completely loosen the seatpost binder bolt in
the frame. Apply penetrating oil to the top of the seatpost
and tap the post with a plastic mallet to vibrate it, which
will help the oil penetrate into the frame. Do this every day
for a week or so and keep trying — the seatpost will free if
you wait long enough. If you're in a hurry, try this: remove
the saddle, flip the bike upside down and clamp the top of
the seatpost in a sturdy vice. Then grab the bike and rock it
from side to side to break the post free.You can also try
heating the post with a propane torch, but do it in a wellventilated area, don't scorch the paint and don't touch the
hot post by mistake.
PROBLEM: The saddle won't hold its position. Every
time you hit a bump it changes, tilting up or down.
The clamp is worn. Replace it. If it's a onepiece post, replace the parts that hold the saddle. Usually,
clamps wear out because the saddle loosens and you keep
riding. Keep it tight and it should last.
SOLUTION:
PROBLEM: You
can't level the saddle. It's tipped slightly
either up or down.
You might be okay riding on it in the slightly
tipped position. If not, set it so that it angles slightly up, then
whack the saddle a few times with a plastic mallet or your
hand to slightly bend the rails (don't overdo it) and get the
saddle where you want it.
SOLUTION:
PROBLEM: The
seatpost is the right size and the bolt in
the frame works, but as you ride, the seatpost slides
down in the frame.
Remove the seatpost and lightly sand it to
rough up the surface.You need to sand only the section of
the post that's inside the frame. Usually, this will increase the
frame's purchase on the post and keep it from slipping.
SOLUTION:
PROBLEM: When you're lowering the seatpost, you
loosen the bolt and the post goes partway down then
stops.
You may have bent the post. Remove it and
lay it on a flat surface to check it. Replace it if it's bent.
Not bent? Check to see that something inside the frame
isn't preventing the seatpost from going lower, like the water
bottle screw or perhaps part of the frame. If the seatpost must
be lowered permanently, you can create the space to lower it
by cutting a section off the end of the seatpost.
SOLUTION:
PROBLEM:
The saddle creaks when you're riding.
Drip a tiny amount of oil around the saddle
rails where they enter the saddle and into the saddle clamp
where it grips the rails. Leather saddles sometimes creak the
same way that fine leather shoes can. There's not much that
you can do about this.
SOLUTION:
PROBLEM: When
you tighten the seatpost binder bolt
on the frame, the seatpost doesn't tighten in the frame.
If you have a two-piece bolt that passes through
the frame ears, it's likely that the bolt is bottomed against
itself and can't tighten the seatpost. Fix this by adding a
washer under one end of the bolt, which will add length
to the bolt and allow you to tighten it a little bit more.
This should then clamp the post in the frame.
SOLUTION:
PROBLEM: You've
tried padded shorts and every saddle
angle but you still get a numb bum from riding.
SOLUTION: Try
different saddles until you find one that's
comfortable. Don't rule out unconventional ones, such as
those that have strange shapes or cutouts.You might also
consider a different bike, such as a recumbent.
PROBLEM: You
loosened the seatpost binder bolt and the
seatpost slid down inside the frame.
Turn the bike upside down and tap on the
frame with a mallet to knock the post loose. With luck it'll
slide right out. No? Try spraying some lube down the frame
and try again (put newspaper on the floor to catch the dripping lube). Still stuck? Fish it out with a long piece of coat
hanger after bending a hook into the hanger's end.
SOLUTION:
SADDLES AND SEATPOSTS 281
Saddle Installation
and Adjustment
-1111•1111•111M
1
If a saddle feels uncomfortable, careful adjustment of its position may
make a big difference. It certainly is critical to providing an overall
proper fit between rider and bike. If adjusting the saddle does not
help, there simply may be a poor match between the saddle and your
anatomy. The only remedy for that problem is to try a different saddle.
Saddle height is determined by how deep the seatpost is set within the
seat tube of the bicycle frame. The tilt and fore-and-aft positions of the
saddle are controlled by the clamp that holds the saddle onto the seatpost.
Old-fashioned saddle clamps have a nut on either side that must be loosened
before the saddle can be removed or have its angle or fore-and-aft position
changed (see photo). The serrations on this type are rather coarse and do not
allow for fine adjustments.
2
or
Another common type of seatpost is one that is fitted with a one-bolt
clamping system, which does allow for very fine adjustments. When
this single bolt is loosened, the rails of the saddle can slide forwards
backwards within the jaws of the clamp, and the tilt of the clamp can be
changed. The bolt is then retightened to hold the saddle in the new position.
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3
Another seatpost is truly micro-adjusting. This type has two bolts
working in opposition to one another (see photo). Changing the tilt
of the saddle involves loosening one bolt and tightening the other.
This system not only allows very minute changes to be made in saddle tilt but
it also holds the adjustment very securely.
4
To completely remove a saddle from a seatpost, you must loosen
the clamp bolt(s) enough for the saddle rails to slip out of the jaws
of the clamp (see photo). The clamp does not need to be this loose
for adjusting saddle position.
--1111■6■'
To set the tilt of the saddle, loosen the seatpost clamp just enough to
allow the nose of the saddle to be easily moved up or down. Place a
straight edge along the top of the saddle and adjust the saddle angle
until the straight edge is parallel with the top tube of the bike (assuming that
the top tube is level with the ground). Then retighten the clamp bolt.
The fore-and-aft position of the saddle should be set according to how your
knees relate to the pedals at a particular point in the revolution of the
crankset. Since the saddle height will also influence this, set it first.
SADDLES AND SEATPOSTS 283
6
To determine your appropriate saddle height, sit on the bike while
wearing riding clothes. It's helpful to have a friend hold you and
the bike upright while you do this. Otherwise, place your bike in
a doorway, near a wall, or in a stationary trainer that holds the bike level
with the ground.
Rotate the crankset to the 12-o'clock and 6-o'clock positions. Then set your
heel on the lower pedal. In this position, you should be able to place your
heel comfortably on the pedal and your leg should be fully extended (see
photo). If there's a noticeable bend in your knee, your saddle is too low.
When pedalling backwards, if you have to rock your hips to reach the
pedals, the saddle is too high. In either case, adjust and retest the height.
7
To raise or lower the saddle, loosen the binder bolt that's located at
the top of the seat tube (see photo). Move the seatpost up or down
as needed. Check to make sure that the saddle is aligned with
the top tube of the bike, then retighten the binder bolt.
Some city bikes and certain models of mountain bike are equipped
with quick-release binder bolts for rapid and frequent changes of
saddle height (see photo). These work quite well and are certainly
convenient if you need to adjust the height of the seatpost. However, this
system makes it easy for thieves to take off with your saddle and seatpost
(the best bet is to remove it and take it with you when you leave the bike).
For most types of riding, once you've determined the ideal height for your
saddle, it should be set there and left alone.
iswimmes
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ILLUSTRATED BICYCLE MAINTENANCE
9
One important thing to watch for when raising your saddle is the
manufacturer's line indicating maximum recommended height (see
photo). Riding with the seatpost raised above that point is dangerous
because there may not be enough post within the seat tube to support your
weight. If you can't set your saddle to the proper height without moving above
that line, then you probably need a bike with a larger frame. A less-expensive
solution is to purchase a longer seatpost.
Any time you pull the seatpost out of the frame, clean it off and
apply a fresh coat of grease before sliding it back in
(see photo). This helps protect it from corrosion and makes it
easier to raise and lower the saddle. This type of maintenance should be done
periodically. You don't want your seatpost permanently rusted into the frame.
Carbon fibre seatposts are the exception to this rule — they should be installed
spotlessly clean and free of oil or grease.
SADDLES AND SEATP051 - 5 285
-4111b
1
•. R■11111•10
After setting your saddle to the proper height, adjust the fore-andaft position. Sit on the bike as you did before, and rotate the
crankset to the 3-o'clock and 9-o'clock positions. Hold a plumb
line (or a string with a weight tied on the end) next to the knee of your forward leg. Place the top of the string in the groove next to your kneecap and
observe where the weight falls. It should touch your foot at a point in line with
the pedal axle (see photo).
If the weight falls in front of the pedal axle, the saddle needs to be moved
back a bit. If it falls behind the axle, the saddle needs to go forward. Loosen
the seatpost clamp and move the saddle in the direction needed. Before
retightening the clamp, check to make sure the tilt of the saddle is still right.
12
41.
Once you've properly set the saddle height, tilt and horizontal
position, check the position of the handlebar and stem. For
general riding purposes, the top of the bar should be set about
2 to 3 cm (1 inch) below the level of the top of the saddle.
As a rough guideline, check the distance between the bar and the saddle
by placing your elbow against the nose of the saddle and extending your
forearm towards the handlebar. The tips of your fingers should fall about
2 to 3 cm (1 inch) short of touching the bar (see photo).
Racers may want the bars a little lower and further away from the saddle;
tourists may want them a little higher and closer to the saddle. If the distance
from the saddle to the bar doesn't fall within a suitable range for your type
of riding, replace the stem to dial in your position.
CHAPTER 16
Pedals
Pedals are not only the means of applying your muscle power
to the drivetrain of your bicycle. They also serve an important
function as a control surface. By moving the pedals to different positions and shifting your weight on them, it is possible to steer your bike more quickly and more accurately, to
increase the rear tyre's traction on climbs and to stabilize the
bike on descents and technical trails.
All of these abilities come with their own specific
demands. Pedals must be strong, have smooth bearings and
complement your footwear. No, this isn't vanity. Simply put,
if your choice of shoes can't maintain contact with your
pedals, the rest becomes difficult, if not impossible.
Bicycle pedals come in many different types and levels of
quality. Some types, the ones most serious cyclists use, are made
to work with special shoes that have cleats screwed onto the
bottoms. These attach to the pedal, improving your pedalling
efficiency immensely. Other pedals cannot be used with cleats,
such as nylon models found on entry-level bikes, and wideplatform BMX pedals used for stunt riding. There are also
pedals designed for both cleats and noncleated shoes.
Although pedals come in many different shapes, almost all
pedals share several common characteristics. At the heart of a
pedal is a spindle that threads into the end of a crankarm.The
inner races of two sets of bearings are located on this spindle:
one at the inside end of the spindle next to the crankarm and
the other at the spindle's outer end. A separate body holds the
outer races of the two bearing sets. Attached to this pedal
body is a pair of 'rattraps', a quill cage or some sort of platform, which acts as the pushing surface for your foot.
Most of the apparent differences between pedals are just
that, cosmetic differences; their internal parts are usually strikingly similar. As you'll see later, that also means that servicing
is usually the same procedure for different types and even different brands of pedals.
platform and clipless. There are many variations within these
basic types, as well as new pedals that come along every year.
In terms of the century-long history of the bicycle, the clipless pedal is a relatively new design. It utilizes a clamping
mechanism that grips special hardware attached to cycling
shoes. It renders toeclips and straps unnecessary. Clipless
pedals are easier to use and are more comfortable than pedals
using clips and straps. Once you get used to them, the best
ones almost instantaneously release your foot in a crash or
emergency. Clipless pedals are now widely used by all types of
cyclists because of the many advantages they offer.
Rubber Block or Nylon
If you see these on a bike, you know right away that it's not
intended for serious use. These pedals shine in commuter situations where the cyclist will most likely be wearing dress
shoes. If you've ever tried the slippery combination of leather
soles on metal pedals, you can appreciate the sticky advantage
of leather on rubber pedals. On the down side, rubber pedals
are usually heavy and nonserviceable, and they don't hold
your foot in the right position when you're pedalling.
Lots of lower-priced mountain bikes and hybrids come
equipped with nylon pedals. These are okay for starting out.
They don't weigh much and they can take a fair bit of abuse.
Sometimes it can be difficult to attach toeclips and straps,
Rubber Block
Pedal Types
When shopping for pedals, it helps to have a good idea of how
you ride your bike. For instance, if you're a road rider who
seldom stops, you probably aren't concerned with a pedal
system that includes a shoe geared to `walkability.' A tourist or
mountain biker finds walking quite important, so a shoe that
has a sole with decent tread and a little flexibility is desirable,
and your choice of pedal will need to take that into account.
Most bicycles are equipped with pedals belonging to
one of five basic types: rubber block or nylon, rattrap, quill.
Standard pedals come in four basic styles: rubber block or nylon,
Platform
rattrap, quill and platform.
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The Clipless Pedal
PEDAL THREADS
JAWS
PEDAL BODY
PEDALS 289
which is a drawback. Most riders use the nylon pedals for a
while and then upgrade to a better system such as clipless.
Rattrap
You'll find rattrap pedals on less-expensive road bikes. Their
thin cage plates allow the use of cleated shoes and also provide
a location for bicycle touring shoes with ridged soles. Unfortunately, the thin cage plates also mean that shoes without
some sort of reinforcement in the soles, like your gardenvariety trainers, will transmit pressure unevenly to the soles of
your feet, and you may develop tender spots on rides longer
than 8 to 15 km (5 to 10 miles). If that happens and you don't
want to switch to a flatter-topped platform-type pedal, buy
touring-style cycling shoes. They have stiffer soles than most
athletic shoes but are still flexible enough for walking.
On many rattrap models, the dustcap at the outer end
of the pedal has no provision for a spanner or other tool
to remove it. Normally, this would mean that the pedal is
unserviceable; that's often the case with inexpensive rattraps.
Sometimes, the cap can be pried off with a small screwdriver
to get to the bearings beneath it. If that doesn't work, it's often
possible to drip oil into the bearings from the crankarm end
of the pedal if you remove the pedal.
There are racers who prefer the rattrap design to clipless
pedals, so rattraps are not limited just to cheap pedals. One
example is the track (velodrome) rider. A rattrap designed for
track use has the twin-cage-plate rattrap design because of the
extra ground, or banking, clearance it provides at the end of
the pedal, which is all-important for racers who are jamming
around a banked oval track. Some track riders produce explosive sprinting power, and it's possible for their feet to come
out of clipless pedals. So instead, they'll use a rattrap pedal
with toeclips and straps (often they use two straps for each
foot), which essentially locks their feet in place.
Quill
The only real difference between quill pedals and rattraps is
that a quill pedal has a curved section of metal that connects
the front and rear cage plates, making the two of them one
part. This creates a stronger structure and also provides a little
more shoe contact area.The latter point is especially important
for people with large, wide feet. For years, this was the only
`acceptable' design for road racing pedals, and Campagnolo
Record pedals were the model for a legion of imitators.
Quill pedals are almost always serviceable. However, you
cannot disassemble a pedal without first removing its dustcap,
and you may have to purchase a special dustcap spanner in
order to remove that part.
Platform
As you might guess from the name, platform pedals offer a
flatter, larger area for foot contact than do other types of
pedals. These pedals are adaptable to different types of shoes,
although some models are designed to accommodate cleats.
People with large feet, downhill racers, tourists and commuters are all riders who like wider pedals.
Platform pedals don't necessarily have a completely flat
body, although some designs approach it. Even pedals that at
first glance might appear to be rattrap or quill can be classified as platform pedals if some parts of the pedal other than
the cage plates are raised high enough to provide additional
shoe contact. This is usually accomplished with the cross
members that connect the barrel of the pedal body to the
cage plates.There are even platform clipless pedals, such as the
Shimano models that many downhillers race on.
Most modern platform pedals are some variation of a single
rear cage plate attached to the wide end of a V- or U-shaped
body.This hybrid design works well with cleats, and it also provides a fair amount of contact surface for touring shoes. In
addition, the internal parts are sometimes identical to those of
rattrap or quill designs from the same manufacturer.
Toeclips for these designs usually mount on the horizontal
surface of the pedal body instead of on the vertical surface of
the missing front cage plate. Because in most cases this means
that the toeclip can move forwards and backwards as well as
side to side, small adjustments can be made to accommodate
shoes of different sizes. If your toeclips don't fit your feet, try
adjusting them to provide more room before shopping for
larger-size toeclips.
Pedals for mountain bikes are either platform style or the
less-common 'bear trap' style, which used to be quite popular
before clipless pedals took off.The former looks like a square
doughnut with a spindle running through it, and the latter
looks like a quill pedal with a round or rounded cage. The
bear trap cage invariably has a notched or 'tooth' profile for a
secure grip on your shoes. Extra gripping power on the platform type is often provided by small flat-top pins that are far
less damaging to your shins than notches or teeth.
Happily, the insides of mountain bike pedals are virtually
identical to those of their road cousins, with one significant
difference: seals and sealed mechanisms are the rule here
rather than the exception.
Clipless
Among both mountain and road enthusiasts, there's been a
long-standing movement away from the traditional pedal, toeclip and toe strap trio towards a system that invariably involves
a pedal/cleat combination, which locks the rider's foot onto
the pedal. This integrated locking feature makes clips and
straps, and their adjustment, obsolete. It's fast and easy to lock
and unlock cleats into and out of these pedals, which makes
them safer and more convenient than other contemporary
pedals. The Look pedal, produced by the makers of Look ski
bindings in 1983, was the first successful clipless pedal.
290 ILLUSTRATED BICYCLE MAINTENANCE
Currently, there are more than a dozen different clipless pedal
systems. Some of the more popular ones include Look, Shimano,
Time and Speedplay.The primary difference between systems is
in the way that the pedal grips the cleat. It's always important to
purchase shoes that are compatible with the cleat system used by
the clipless pedals that you plan to purchase.
Toeclips
These days, although most top-quality bikes come with clipless
pedals, you'll find toeclips and straps on older models and entryto medium-level bikes. There is a misconception that the purpose of toeclips is to prevent your feet from slipping forward on
the pedals; in reality their primary function is to hold up the toe
strap loops so you can easily place your feet through them. The
strap's function is to prevent your feet from slipping off the
pedals, particularly if you wear cleated shoes that permit you to
pull up slightly on the back side of your pedalling circle. Even
under racing conditions, toe straps are not normally cinched
down tightly. This is done only at the start of particularly steep
hills and just before finish-line sprints.
Under normal riding conditions, most people don't keep
their straps tight, just without much slack. That way, the straps
provide a measure of security without preventing you from
being able to quickly remove your feet from the pedals. With
a little practice, the technique of lifting your foot up before
you pull it back out of the strap becomes automatic.
Toeclips should be just long enough to give a little clearance for your toes when the balls of your feet are centred over
the pedal spindle. The right-length clip should have a little
clearance for your toes. Your toes should never be jammed
against the clip. Toeclips come in different sizes. If you have
really large feet, you may need to add spacers between the
toeclips and pedals, which can give you the needed clearance.
Crank Brotheres Eggbeaters
The minimalist design of these
four-sided pedals allows them to
shed mud easily.
Time Atac Z
This downhill-intended pedal
adds a large platform to Time's
tried-and-true retention system.
Keeping Clipless Pedals Working
A clipless pedal must hold the cleat tightly to keep the rider's
foot secure and to prevent accidental release. Reduce cleat
wear by not walking in them. Except for walkable cleat
designs, which are recessed, most clipless cleats wear faster
than regular types because they are thicker and protrude more
from the shoe sole. It's better to remove your shoes and ruin
your socks if you have to walk any distance.
You can tell that the cleats are worn if you have excessive
foot movement on the pedals. Some clipless models allow
your foot to swivel, but when a cleat becomes worn, the shoe
begins to move in several directions and can rattle around on
the pedal. When a Shimano SPD cleat wears enough, it
becomes difficult to get your feet out of the pedals.You can
also identify a worn cleat by comparing it to a new one.Worn
cleats should be replaced before they get so bad that they
release prematurely or, in the case of SPDs, stick.
The other part of the release mechanism is the cleat-gripping
pedal hardware. Look, Shimano and Time pedals use plastic,
carbon and steel parts, and constant use can grind them down.
The parts may also become loose and vibrate. If the mechanism
loosens, the fit between the cleat and pedal is not secure enough,
and engagement and release suffer.Additionally, you may develop
an annoying squeak that's most noticeable when climbing. The
noise is made by two pieces of plastic or steel — the cleat and the
pedal backplate — rubbing against each other. You can temporarily quiet plastic parts by applying oil to the pedal and cleat,
but if the noise is chronic, a more lasting solution is to replace the
hardware. Oiling SPDs is considered regular maintenance, and
the cleats shouldn't need replacing until you start to experience
difficulty releasing them.
In wet and cold conditions, the small cleats and retention
mechanisms common on mountain biking shoes and pedals
Crank Brothers Candy
Add a small platform to an
Eggbeater pedal, and you
get a Candy.
Campagnolo
These road-specific pedals
offer a wide platform for
extra stability.
can become clogged with mud and snow, and they then resist
engaging. Manufacturers have recognized this and improved
cleat and pedal shapes, but some riders still experience difficulty in extreme conditions. A trick to alleviate clogging is to
spray your cleats and pedals with a non-stick cooking spray or
some similar product. Just as it can help keep your eggs from
sticking to the frying pan in the morning, it can keep mud
and ice off of your cleats and pedals during your sloppy rides.
pedals that gauge cleat position. They are installed on your
crankset and your bike is mounted on an indoor trainer.As you
ride, the mechanic can determine how to adjust your cleats for
best performance by observing special wands that are attached
to the pedals. The final position will be biomechanically correct for your knees. This greatly reduces the chance of knee
injuries and ensures easy entry into the pedals.
When to Service Pedals
Tension and Float Adjustments
On most clipless pedals, there's a provision for adjusting how
hard it is to get in and out of the pedal. Mountain bikers need
to get in easily, but even more important is getting out in a
hurry when the trail turns dangerous. Look for a small bolt on
each end of the pedal or inside the pedal body. These are
usually marked in some way, and they're almost always turned
anticlockwise to loosen the tension setting and turned clockwise to tighten the tension.
Another consideration is float, a feature that allows your
foot to swivel slightly to protect your knee. Certain pedal
designs rely on the cleat to provide the float, so it's possible to
simply switch to these other cleats to make the pedals fixed or
floating. Some pedals have set screws that are adjusted to
reduce or increase the amount of float on the pedals.
With new clipless pedal systems coming out all the time,
the best bet is to study your owner's manual to understand all
the adjustments that are offered by your type of clipless pedals
and how to dial them in.
Cleat Adjustment
While cleat adjustment is not really bicycle maintenance, it's
an important consideration when setting up cleated shoes.
Cleats hold your feet on the pedals in a certain position. The
problem is, it's possible to get the cleat in the wrong position.
Everyone has a natural gait or position where his or her foot
sits on a pedal. When the cleat is adjusted incorrectly, it forces
you to pedal with your foot in an unnatural position, which
puts stress on the knee and often leads to injury. Additionally,
for clipless pedals, if the cleat is not adjusted properly, it's more
difficult to click into the pedals.
These days, many pedal systems include a float feature,
meaning that the cleats move slightly on the pedals, allowing the
feet to pivot laterally. This float is designed to allow the feet to
find their natural position throughout the pedal circle. It's a mistake to assume that because there's some float in the cleat, it's
okay to set the cleat position any which way. The proper cleat
position will be at the centre of the cleat float.That way, your feet
can move either way, as necessary, while you're riding.
The best way to adjust cleats is to have it done by a shop that
uses the Fit Kit. Go to www.bikefitkit.com for a list of shops
offering this service. This bicycle-sizing system includes Rotational Adjustment Devices, which are actually two special
There are four general pedal conditions that indicate that it's
time for service. The first is simply the passage of time. In the
absence of any other condition, mountain bike pedals ought
to be serviced every 6 months, and road models should be
serviced yearly as preventive maintenance. Open up the pedal
and make sure that you don't have water or other contaminants trapped inside. (Those seals can work both ways.) These
problems are difficult to detect from the outside.
The second condition is when you hear or feel a maddening
click with every complete revolution of the pedal or crank.This
could result from a loose bottom bracket cup, crankarm or toeclip bolt, so check those easily fixed problems first. If those parts
are all tight and the click continues, it's probably something
within the pedal bearings. If you've recently overhauled your
pedals, try to isolate the offending side and service only that one.
If it's been a while since their last servicing, you may as well do
both of your pedals now. Ironically, you'll most likely never find
the small bit of dirt that causes the problem, which almost always
goes away after cleaning and regreasing.
The last two conditions are easily detected with a simple
inspection that you should perform regularly, either before or
after every few rides. Hold each pedal body with your fingertips
while you rotate it around the crankarm. A slight roughness to
the touch suggests that there may be dirt in the pedal bearings or
that they may be slightly out of adjustment. If the pedal binds,
you have a very dirty or a badly adjusted set of bearings. If the
pedal works okay to this point, try to rock it back and forth.An
adjustment is called for if you discover any play in the bearings.
Keep in mind that it's not worth the effort to overhaul
cheap pedals. Parts are rarely available so it's best to upgrade
to a better model.
Removing Pedals
Pedal removal is something you don't do frequently.You might
need to remove pedals to fit your bike into a shipping box so
you can take it on vacation with you or to an event. Removing
the pedals makes servicing them easier. And you'll definitely
have to remove them to upgrade to better or different models.
Many people have difficulty removing pedals. It's usually
because they don't know one fact: the left pedal is reversethreaded. This means that you must turn it clockwise to
loosen it. The right pedal is regular-thread. It's turned anticlockwise to loosen. The left is the opposite because if it were
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ordinary-thread, the action of pedalling would cause the pedal
to loosen on the crankarm. Since it is reverse-threaded, the
pedalling action turns it in the direction that will tighten it.
It can take considerable force to loosen a pedal that's been
adequately tightened or one that's been on a bike for some
time.There are some sharp things down there, too, such as the
chainrings, which can cause injury. When you're removing
the right pedal, it's a good idea to shift onto the largest chainring. The chain will prevent you from slipping and getting
jabbed by the chainring teeth.
Sometimes pedals seem stuck. If you're sure that you're
turning them the right way but they won't budge, one of
these methods should get the pedal off: add a cheater bar to
your pedal spanner, heat the crankarm slightly with a propane
torch or remove the entire crankarm and place it in a vice,
then use the spanner and cheater bar.
Cleaning and Greasing
You can perform certain adjustments on some pedals while
they're still screwed onto the crankarm, but don't try to disassemble a pedal without first removing it from the bike.
You'll probably need a thin 15 mm spanner like that found at
the small end of the fixed cup spanner in most bottom
bracket tool sets. Remember that the direction in which each
pedal is threaded is the same as the side of the bike that it's
on.That means that as you straddle the bike, the pedal on your
right side unscrews anticlockwise, while the pedal on your
left side unscrews clockwise. In each case, to remove the
pedals, turn the spanner towards the rear of the bike.
To disassemble the pedal after taking it off the crankarm,
hold its threaded end down in a vice with soft jaws or
between two pieces of wood. Remove the dustcap with the
appropriate tool. Underneath the dustcap, you'll find the
locknut and cone for the outboard bearings.
At this point, determine whether the pedal you are
working on is one you can easily disassemble or whether you
might prefer to take it to a shop. Some pedals, including most
clipless models, have precision sealed-cartridge bearings that
require special tools for service. Sealed bearings require less
maintenance than loose bearings because it's more difficult
for dirt and water to enter. However, they can wear and
develop play. When they need to be replaced or serviced, you
might prefer to have shop personnel do the job. All that's
visible of cartridge bearings is the seal (the bearings are
underneath it), which is a black plastic ring that often has
writing on it. Regular bearings, however, are easy to spot
when you remove the dustcap.They are small shiny steel balls.
If the pedal has regular bearings, hold the cone in place with
one spanner while you loosen the locknut with another. In an
emergency, if you don't have a spanner for the cone, you can
sometimes hold it steady by wedging a screwdriver between it
and the inside of the pedal body. Unscrew the locknut and cone.
Pick the ball bearings out of their race with a pair of
tweezers or, holding the spindle firmly within the pedal body,
turn the pedal upside down and dump the bearings into a
container. Before you go any further, count the ball bearings
— if you drop any during disassembly and the inside bearing
has a different number of balls, you may not know if you
found all of the ones you dropped. Don't lift the pedal body
off the spindle, or all the inboard bearings may drop on the
floor.Turn the pedal upside down if it isn't already, and lift the
spindle out of the pedal body. If the pedal has a rubber seal,
gently pry it out of the body to make it easy to remove the
inboard ball bearings. Count them before any get lost.
Replace your ball bearings with new ones. The old ones
are invariably slightly out of round, which will make adjusting
them difficult when they're reassembled into the pedal. Most
loose-ball pedals use .-inch bearings, but take a sample to the
bike shop to make sure you get a good match.
Use a rag to clean everything well. Clean all metal parts
with solvent, but keep the solvent away from plastic parts and
rubber seals. Use something mild, such as alcohol, to clean
those parts. Make sure that you remove all the old grease from
the inside of the pedal body. If the inner end of the pedal body
has a rubber seal that you didn't remove and you can't get the
area behind it clean, gently pry it out of the body.
If any of the bearing races have pitted areas or more than
a slight groove, look for replacement parts. Availability varies
considerably among manufacturers.
Apply a layer of medium-weight grease to the races in the
pedal body. Hold the inside end up and place the required
number of ball bearings in the layer of grease. Repeat for the
outer end. Carefully place the spindle halfway back into the
body, then apply additional grease to the ball bearings either
directly or by loading up the area next to the inside cone. Seat
the spindle and turn it to make sure it isn't binding. Grease
that oozes out of the inboard bearings indicates that the bearings are fully packed and will resist contamination.
Holding the spindle in the pedal body, turn the assembly
over and thread the cone onto it a couple of turns. Hold the
cone still, and turn the spindle. This will draw the cone onto
the bearings without scrambling them. Add the lockwasher
and locknut. Now you're ready to do a pedal adjustment.
Pedal Adjustment
The spindle should turn smoothly with no play in the bearing
adjustment. Snug the locknut and feel the adjustment. If it's
tight (binding), loosen the locknut, back off the cone, tighten
the locknut and recheck the adjustment. For play, back off the
locknut and tighten the cone, then tighten the locknut. Continue the process until the pedal turns smoothly on the
spindle without any rough feel.
Replace the dustcap and you're done. Take it easy when
you tighten it; most dustcaps are made of plastic.
PEDALS 293
Pedals may seem like an insignificant part of a bicycle,
something you should be able to take for granted. While it is
true that proper pedal adjustment is less critical to the safe
operation of a bike than proper adjustment of its brakes and
headset, there is still no point in neglecting this process.
Smooth-turning pedals add a lot to the joy and efficiency of
cycling. All it takes is a little time and proper maintenance.
TROUBLESHOOTING
PROBLEM: The
pedal squeaks when you're pedalling.
Spray the cleats with lube (just don't walk in
the house in your now-oily shoes).
PROBLEM: Even
though you're using a good pedal
spanner, you can't get the pedal off.
SOLUTION: Make sure that you're turning the pedal the
right way. The right pedal is turned anticlockwise to loosen
it, but the left pedal is turned clockwise. It's still not coming
off? Add a cheater bar to the pedal spanner. Still stuck? Heat
the crankarm with a propane torch slightly. Or, remove the
crankarm, put it in a vice and use a long cheater bar on your
spanner to remove the pedal.
PROBLEM: You need to replace your clipless pedal cleats
but the bolt heads are full of crud or damaged.
SOLUTION:
PROBLEM: The
cleats won't engage when mountain
hiking in wet or cold weather.
Spray a non-stick cooking spray on the cleats
and pedals before a ride so mud and ice won't stick.
SOLUTION:
PROBLEM: You're having trouble getting out of your
SPD-style clipless pedals.
SOLUTION: The cleats have probably worn and can no
longer spread the pedal jaws to release. Install new cleats.
PROBLEM: You
can't find toeclips to fit your huge feet.
Put washers between the pedals and toeclips for
additional clearance, or try different pedals with wider cages.
SOLUTION:
PROBLEM: With
SOLUTION:
Clean them out with an awl, and then force a
hex key in by tapping on it with a hammer. If you can get
the hex key to reform the hole in the bolt, you should be
able to loosen the screws.
SOLUTION:
PROBLEM: You
installed the pedals in the wrong sides
before you realized it. Now the left pedal is in the right
crankarm and the right is in the left.
Next time, look at the pedals right at the
threaded portion of the spindle. Usually, pedals are marked
with an R or an L designating right and left. (The R pedal
is for the right crankarm and the L is for the left.) All you
can do to fix pedals threaded into the wrong sides is to
remove the pedals and hope for the best. Usually, threading
them into the wrong sides destroys the threads in the
crankarms. If that's the case, you'll need to replace the
crankarms. The pedals should be reusable, as the crankarm
threads are soft and shouldn't damage the pedal threads.
SOLUTION:
each pedal stroke, you hear a click.
A pedal may have loosened. Tighten them.
PROBLEM: You're
having trouble getting into your Look
clipless pedals.
Make sure that the cleat is installed correctly
on the shoe. If have small feet, you may have curved the cleat
too much when tightening it to your shoes.The cleats must
be fairly flat to engage correctly. Shim the edges with leather
to flatten the cleat.
SOLUTION:
PROBLEM: Your clipless pedal cleats will not come off
because the bolts are damaged or frozen.
a penetrating lubricant, then use a punch
and hammer to loosen the screws. Use a pointed punch and
strike the bolt to make a small divot. Put the point of the
punch into the divot and strike the punch so that the force
pushes the screw anticlockwise and loosens it.
SOLUTION: Apply
PROBLEM: You
In some shoes, it's possible to lift up the liner
inside the shoe and replace the threaded insert. If not, it's
usually possible to cut a hole in the shoe that's just large
enough to allow you to perform surgery and replace the
threaded insert. Then you can glue or tape the liner back.
SOLUTION:
PROBLEM: You
need to remove the pedal but can't find
a place to fit your pedal spanner.
SOLUTION: The pedal is probably installed and removed
with a hex key only. Look at the back of the crankarm to
see if there is a hex-shaped hole in the pedal spindle.
stripped the threaded plate in your shoe.
294 ILLUSTRATED BICYCLE MAINTENANCE
Mountain Bike Clipless
Pedal Maintenance
1
Click-in convenience comes at the cost of more upkeep, primarily
because cleat engagement mechanisms complicate the pedal design.
Here are adjustment and repair tips for many common mountain
bike clipless pedals.
If you're having trouble getting in or out of a new pair of pedals, make sure
the cleat engages the pedal properly. The shoe's sole can interfere and prevent
proper engagement. Trim it with a sharp knife to get the clearance needed. Still
problematic? Most pedals have a bolt on the front and back (or just the rear on
single-sided pedals) for spring tension adjustment. Turn these screws anticlockwise (see photo) to ease entry and release. Lightly lube the cleat and jaws.
Snug the screws that secure the jaws atop the pedals because they
can loosen. Many models also have screws to check on the pedal
ends facing the crankarms.
With enough use, cleats wear and it begins to get difficult to escape the
pedals. At the first signs of unreliable release, for safety's sake, replace
the cleats. Mark the position by scratching indicator lines in the soles.
If the cleat bolts won't budge, use a hammer and punch to drive the screws
anticlockwise (see photo), or use a propane torch to slightly heat them (wrap
wet rags around the sole to prevent it from melting). Grease the bolts and the
nuts inside the shoes. Align and install the new cleats.
To remove the pedals, shift onto the large chainring, place the pedal
in the 3-o'clock (right side) and 9-o'clock (left) positions, attach the
pedal spanner so that it's nearly in line with the crankarm and push
down to loosen and remove the pedals (see photo). If they won't turn, ask a
strong friend to help, use a cheater bar on the spanner or remove the
crankarm, put it in a vice and try again (remember the left pedal turns clockwise to loosen).
When the pedals are off, spin the spindles between your fingers. If they turn
without resistance or feel dry, tight, loose or rough, regrease the bearings. If
there's a hydraulic resistance while turning the spindle, the grease is still fine.
PEDALS 295
Most of Shimano's pedals, as well as some other brands, come apart
by unscrewing and removing the spindle and bearings as a unit. Use
the pedal spindle tool (see photo) or appropriate tool to unscrew the
spindle/bearing assembly. Hold the right pedal in the vice with the spindle
upright, and turn the tool clockwise to unscrew the spindle. To unscrew the
left pedal spindle, turn the tool anticlockwise.
MOW
in
Some clipless pedals have a dust cap that you must remove to access
the bearings. Some, like Shimano's PD-M535, use a simple plastic
cap that can be pried out (see photo). Others require the use of a
hex key or a flat screwdriver. In most cases, it's relatively obvious how the
cap is removed. With the number of different designs in current use, it's best
to consult the owner's manual before delving too deep.
6
If you add grease every few months, the pedals may never need
new parts. For most Shimano models and similar pedals with cartridge spindle/bearings, put about 15 ml ('4 ounce) of grease inside
the pedal body and reinstall the spindle assembly, which will regrease all the
bearings (see photo). Lube Speedplay pedals by removing the tiny bolts in the
ends and pumping grease in with a needlenose grease gun. For Shimano
pedals with a plastic dust cap, remove the cap and push grease into the
exposed bearings. Pull back the rubber seal on the spindle, and push fresh
grease into the inside bearings.
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ILLUSTRATED BICYCLE MAINTENANCE
Shimano SPD Pedal Bearing
Overhaul
1111■=1111IF
1
Shimano SPD pedals are nicely sealed and should resist penetration by
water and dirt under most conditions. Check the pedals by removing
them from the crankarm, turning the spindles and feeling for play. If
the spindles turn with a hydraulic smoothness and there is no play when you
push and pull them, the pedals don't need service. If the spindles turn roughly
or you feel play, take the following steps to refurbish them.
You'll need a Shimano spindle removal tool and a spanner that fits on it
to separate the spindle from the pedal body (see photo). You can use an
adjustable spanner. (It's also possible to place the spindle removal tool in a
vice and turn the pedal to remove the spindle.)
Place the tool on the splined portion of the spindle, attach the spanner
to the tool and turn the tool to unscrew and remove the spindle (see
mai photo). If you look closely at the face of the tool, you'll see that it's
marked to show which way to turn the tool for both the right and left pedals.
Turn the tool clockwise to loosen the right spindle and anticlockwise to remove
the left.
Don't force the tool. If it doesn't turn with a little pressure, you may
be turning it the wrong way. If it doesn't turn, apply pressure in the
other direction. After a few turns, you should be able to pull the
spindle out of the pedal.
PEDALS 297
Clean off any dirt that's on the end of the spindle, which is where one
of the bearing cartridges resides. Clean off any contaminated grease
or dirt that you find on the rest of the spindle. Use a swab to wipe
any dirt, contaminated grease or water from inside the pedal body.
Place a dollop of grease on the end of the spindle assembly (see
photo). Place a small dollop (about the size of a marble) inside the
pedal body. Turning it by hand only, screw the spindle into the pedal
a few turns. Extract it and repeat. This will push the fresh grease into the
spindle body and work it along the spindle.
To finish the job, install the tool on the spindle and thread the spindle
back into the pedal body fully by hand (see photo). Sometimes the
new grease will cause a hydraulic resistance that can damage plastic
parts inside the pedal if you force the spindle. If the spindle resists at any
point, extract it and start again. When you have hand-turned the spindle all
the way into the pedal, use the spanner to hold the tool and tighten the
spindle. Don't overtighten – it needs little effort to remain tight. The pedal
spindle should now turn smoothly and without play.
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Conventional Pedal Repair and
Maintenance
1
Pedals are always easiest
to
maintain when they are removed from the
crankarms. Keep in mind that a left-hand pedal threads in the opposite
direction from a right-hand pedal. To loosen a pedal for removal, rotate
its crankarm forward (towards the front of the bike), put the pedal spanner on
the pedal, then push the spanner down towards the ground. This procedure
will work for both pedals. To disassemble a pedal, remove the dustcap from
the end of the spindle opposite the threaded end. On many models, you pry
off the dustcap with a flat-blade screwdriver or similar tool (see photo). If you
have a bench vice, use it to hold the pedal in an upright position while you disassemble it. If you don't have a vice, hold the pedal with locking pliers or by
hand. It won't make the job that much more difficult.
2
Once the dustcap is off, you'll see a locknut on the end of the spindle.
It holds the spindle and the bearings inside the body of the pedal.
Hold the spindle with a 15-mm ('/-inch) spanner while you use an
appropriately sized spanner to loosen the locknut inside the pedal body. A
keyed washer usually separates the cone and locknut, making it possible to
loosen the locknut without holding the cone directly.
Remove the locknut and the lockwasher behind it. Thread off the
cone. Be careful as you remove the cone because there are bearings
behind it that can easily fall out and become lost.
To remove the bearings, either turn the pedal upside down and shake the
bearings into a container or use a pair of tweezers to pick them out one by
one. Make sure that the spindle remains inside the pedal body while the first
set of bearings is being removed. As soon as the outer bearings are out,
record the number so you'll know how many replacements to put back in.
PEDALS 299
4
Turn the pedal over and pull the spindle out. If the spindle has a
rubber seal, this may take some effort. Remove the second set of
bearings, count them and record their number. Take a sample with
you to buy replacements of the same size. Clean all metal parts with solvent.
For plastic parts and rubber seals, use something mild, such as alcohol. Get
all of the old grease out of the inside of the pedal body. Inspect the bearing
races. If they are pitted, you'll need to replace them.
When you have a complete set of clean and usable parts, reassemble
the pedal. Pack medium-weight grease into the bearing race and
install new sets of bearings. As you insert the spindle, it's important
that you don't turn it because that can dislodge the bearings. Turn the pedal
over. If you just screw on the cone, you'll scramble the bearings in the top
race, forcing you to reposition them and try again. Hold the bottom of the
pedal spindle and push up to keep the spindle fully inserted in the pedal.
Holding the pedal spindle like this, screw the cone only a couple of turns. To
seat the cone on the bearings, turn the bottom of the spindle while you hold
the cone. Don't turn the cone or the pedal, just the spindle. This will draw the
cone onto the bearings without unseating them in their race. Put the lockwasher back in place and thread the locknut back on the end of the spindle.
Make sure that the locknut is loose enough to give you some working room,
then back the cone off until you know it's too loose. Slowly turn the cone
down. Once you reach the point where most of the play is out of the adjustment, hold the spindle with a 15-mm ( 3/4-inch) spanner and use a second
spanner to tighten the locknut. Spin the pedal. If you feel any binding, your
adjustment is too tight. If binding is no problem but you feel play in the bearings when you wiggle the spindle up and down, loosen the locknut and turn
the cone down a little more. Tighten the locknut and check the adjustment
again. Work in small increments in this way until you reach the point where
there is neither binding nor looseness in the adjustment. Then make sure that
the locknut is firmly fastened, and replace the dustcap.
-
11111111111111=111111,
11M11,
-,111111W.
6
When installing a leather toe strap, put a single twist in the strap as
you run it between the two sides of the pedal. This prevents the strap
from shifting position.
Lace the strap through the upper end of the toeclip, then press the buckle
open and run the end of the strap straight through both the inner and outer
plates of the buckle (see photo). When you release the buckle, the end of the
strap should be caught between the cylinder of the inner plate and the teeth
in the outer plate of the buckle.
300 ILLUSTRATED BICYCLE MAINTENANCE
Look Pedal Bearing Overhaul
Look pedals were one of the first clipless types and are perhaps the
most widely used ones today. The backing plates on newer models
rarely wear out and do not need service. If you have problems in this
area, the best remedy is to install new cleats on your shoes. (Also, avoid
walking on your cleats, which wears them.) The pedal spindles employ
cassette-type cartridge bearings. While these are quite resistant to dirt and
water, they still require service occasionally. To service Look pedal bearings,
remove the spindle cap with a 15-mm ('/-inch) open-end spanner or pin tool.
The cap also serves as the outer bearing retainer. Therefore, a loose cap will
allow the pedal to rattle on the spindle. Keep the cap tight when in use.
While holding the pedal spindle near its threads with the 15-mm (3/4-inch)
spanner, loosen the spindle end nut with an 11-mm ( 1A-inch) socket
spanner (Note: the left spindle nut is left-hand threaded, while the right
one is right-hand threaded.) You'll feel resistance because the nut has a nylon
bushing. (The left and right nut bushings are different colours for identification.)
Stop when the nut protrudes from the pedal body but still has three or four
threads engaged. Tap the nut against your workbench, or free the spindle with
a wooden or plastic mallet. Unscrew the nut completely and pull the spindle
out of the pedal. Wipe off the grease and inspect the spindle's bearing surface
for roughness or discolouration. If you find any, replace the spindle.
3
The outer bearing slip-fits into the pedal and can be removed by gently
poking it from behind with a driftpin or screwdriver (see photo). Soak
the outer bearing and pedal body/inner bearing in solvent to loosen
the dirt and old grease.
PEDALS 301
d
Use a bottle brush to gently clean the inside of the inner bearing
(don't dislodge any of the needle bearings) and the outer bearing If
you have access to compressed air, blow the bearings dry. If not,
rinse them with clean solvent and let them air-dry on a rag or paper towel.
5
Work some grease into the dry bearings. Lightly grease the entire
inner portion of the spindle and insert it into the pedal (see photo).
4,4.,Slide the outer bearing into the pedal body so the spindle threads
protrude through the centre. Thread on the correct spindle nut, hold the spindle
with the 15-mm ( 3A-inch) spanner and tighten the nut with the 11-mm (',-inch)
spanner. Don't overtighten! The spindle should barely protrude from the nut
when tight and should rotate freely within the pedal body until the spindle cap
is attached.
6
Screw on the spindle cap and gently tighten it with the 15 mm
spanner or pin tool. Once you have finished, spin the pedal to make
sure it rotates easily
CHAPTER 17
Gears
With a limited range of motion and gross power output, the
human body is not well equipped to move very fast, very
far, for very long. There are, of course, super-athletes who run
double marathons, but what of the rest of us: the mere
mortals? How can we get about more efficiently?
The bicycle is a way that even the most average of us can
move quickly over distances with much less effort than would
be possible on foot. This is all thanks to gearing.
Add the convenience of variable gearing provided by a
derailleur drivetrain or internally geared hub, and our range
extends for miles. Low gears allow you to climb steep grades,
and high gears can propel you as fast as your nerves will
allow coming back down. Of course, we mustn't forget those
perfectly comfortable medium gears that are ideal for a casual
ride to the corner store or a relaxing cruise to the ice cream
shop by the beach.
But what is the right medium gear? What makes a good
high gear or low gear? Gearing is often misunderstood. So
here, we take some time to explain the basics of gearing.
The Lingo
Designated gear sizes date back to the days of highwheelers,
those antique bikes with the large front wheel. With a highwheeler, each complete revolution of the pedals resulted in a
single wheel revolution. The diameter of the front wheel was
a gauge of how fast it was possible to go. A highwheeler with
a 56-inch-diameter front wheel was faster than one with a
48-inch-diameter front wheel but was harder to ride up hills.
Today, we still refer to gears by the equivalent highwheeler
size that would give you the same distance travelled per pedal
revolution as the distance you would cover with one pedal
revolution on your 26- or 27-inch wheel. For example, when
you ride on a 52-tooth chainring and a 14-tooth cassette cog,
your gear ratio is 52/14, or 3.714. If you multiply that ratio
by the wheel diameter of a standard derailleur road bike — 27
inches — you have a 100-inch gear. (See the tables on pages
308 and 309 for the gear-inch equivalents of most bicycle
gear combinations.)
Notice that the gear ratio is determined by dividing the
number of teeth on the chainring by the number of teeth on
the rear cog — 54 divided by 14 equals 3.714. A 52-tooth
chainring and a 14-tooth cog are in a ratio of 3.714 to 1. If
the chainring is reduced in size to 30 teeth and the size of the
rear cog increased to 30 teeth, it would be a 1-to-1 ratio.
Multiplying this ratio by the wheel diameter, we find that this
combination of chainring and cassette gives us a gear of only
27 inches.The difference in the size of these numbers reflects
the different levels of effort needed to propel a bicycle using
the two gears. A 100-inch gear will move you 3.714 times as
far down the road with each revolution of the pedals as will
a 27-inch gear. However, the smaller gear will allow you to
pedal up a steep grade with a heavy load, while the larger gear
is useful only on fast descents or, if you are quite strong, on
flat terrain.
Later in this chapter, charts display common road and
mountain bike gear ranges, giving some different chainring
and cassette cog combinations. For now, we want to make
clear the logic of how these numbers are derived and what
they mean in relation to one another.The higher the number,
the greater the size of the chainring in relation to the cassette
cog, and the greater the effort needed to use the gear (in
other words, the bigger the chainring, the harder it is to
pedal). Conversely, the lower the number, the smaller the size
of the chainring in relation to the cassette cog, and the less
effort needed to propel the bike (in other words, the smaller
the chainring, the easier it is to pedal).
From this, you can see that there are two ways you can
move to a gear that is larger (harder to pedal) or smaller
(easier to pedal) than the one you are in. To move to a larger
gear (harder), you can either shift the chain onto either a
larger chainring or a smaller rear cog. Either move will
increase the gear ratio and thus the size of the gear. Conversely, you can move to a smaller gear (easier) by shifting
onto either a larger rear cog or a smaller chainring.
Sample Road Gearing
Cassette cog
12
13
14
15
16
17
19
21
23
26
*In chain inches
Inner chainring
39*
88
81
75
70
66
62
55
50
46
41
Outer chainring
53
119
110
1 02
95
89
84
75
68
62
55
304
ILLUSTRATED BICYCLE MAINTENANCE
Power Management
FRONT DERAILLEUR
REAR COG SET
(CASSETTE)
LARGE CHAINRING
SMALL CHAINRING
(GRANNY RING)
MIDDLE CHAINRING
GEARS 305
The manner in which bicycle gearing systems are set up
makes the distinction between larger and smaller gears easy to
remember. The smaller the chainring or the larger the rear
cog, the closer it is to the bicycle frame; the larger the chainring or the smaller the cog, the further it is from the bicycle
frame. Thus, the lowest gear — the easiest to pedal — is formed
with the chain all the way to the inside on both front and
rear; the highest gear — the hardest to pedal — when the chain
is shifted as far to the outside as it can be, both front and rear.
To simplify references to different gear combinations when
you're planning or analyzing a gear pattern, it's helpful to
assign numbers to the cassette cogs and letters to the chainrings. Mentally number the cogs consecutively from inside to
outside in order to reflect their relative effects on gear size.
Thus, the innermost cog is referred to as 1, and the outermost
is referred to as 6, 7, 8, 9 or 1 0 (depending on the total
number). In a similar way, use an L to refer to the inner chainring (the one that produces lower gears) and H to refer to the
outer chainring (the one that produces higher gears). In the
case of triple-chainring cranksets, add the letter M to designate the gears formed on the middle chainring.
Using this code, the gear formed on the inner chainring
and the inside cog is L-1, and the gear formed on the outer
chainring and outside cog is H-8 (or H-9 or 1-1-10,
depending on whether there are 8, 9 or 10 cassette cogs).This
works for either a double- or triple-chainring system, as the
gears formed on the middle ring of a triple will be identified
as M-1, M-2 and so on.
The most common method used for charting a gearing
system is to write the chainring sizes across the top and the
cog sizes down the side of vertical columns, calculate all
combinations of the two (or use a gear chart to find them)
and list the results in gear inches within the columns. In this
chapter, we've provided charts of this type for two common
gear arrangements.
The primary value of creating gear charts of this sort is that
they let you make a quick numerical comparison so you can
figure out how many usable gears you have and how large or
small the jumps are between gears. Once you know this, you
may decide to modify the gearing to better suit the terrain or
your strengths as a rider.
The ease of altering your gearing, however, depends on
your drivetrain components. Some cassettes and chainrings
are easy to modify, and others are more difficult. It's almost
always easy to install lower or higher gears, however, which
satisfies most riders' requirements.
When analyzing your gears, keep in mind that two
combinations are usually not used: the small chainlying/small
cassette cog combination and the large chainring/large
cassette cog combination.These 'crossover' gears put the chain
at an extreme angle, and it's best to avoid them because they
wear the chain and cassette cogs rapidly. Because of this,
they're generally considered unusable gears and are not shown
in gear charts.
Gearing Simplified
Only a few years ago, it was necessary for tourists, mountain
bikers and even commuters to customize gearing to get the
gear ratios they needed. Gearing was limited because freewheels were available only in five- and six-cog models, which
required some compromise in gear choice to get the low and
high gears you needed, a reasonable range in between and a
smooth shift sequence.
These days, with index drivetrains (ones where the shift
levers click into position with each shift) that shift beautifully
under the most adverse conditions and nine- and even tencog cassettes that provide a wide gear range, there's far less
need to customize drivetrains. Perhaps predictably, options
have been reduced as well. Index shifting relies on precisely
spaced cassette cogs and chainrings, so most manufacturers
make a limited range of replacements. This makes it difficult
to change the gearing too much. Fortunately, the options that
are offered satisfy most needs and work best with the index
system for which they're designed.
To give you an idea of modern gearing, here are examples
of common road and mountain bike drivetrains. The road
bike may be equipped with 39- and 53-tooth chainrings and
a 12-, 13-, 14-, 15-, 16-, 17-, 19-, 21-, 23- and 26-tooth tenspeed cassette. The mountain bike may have 22-, 32- and 42tooth chainrings and a 11-, 12-, 14-, 16-, 18-, 21)-, 23-. 28and 34-tooth nine-speed cassette.
The road bike gearing is an example of what you'd find on
many racing bicycles. A 39/26 lowest gear combination
results in a 41-inch gear, which is low enough for a fit rider
to use to tackle most paved hills at a reasonable pace. A 53/12
highest gear produces a 119-inch top end, which is a 'tall'
enough gear for all-out sprinting and pushing the pace down
hills. In between, there are one-tooth jumps on the low end
of the cassette, which allow a very gradual change in effort
Sample Mountain Bike Gearing
Cassette cog
11
12
14
16
18
20
23
28
34
*In chain inches
Inner chainring
22*
52
48
41
36
32
29
25
20
17
Middle
chainring
32
76
69
59
52
46
42
36
30
24
Outer
chainring
42
99
91
78
68
61
55
47
39
32
306
ILLUSTRATED BICYCLE MAINTENANCE
that's ideal for a racing or training rider to fine-tune the gear
while jamming on the flats or descending. On the upper end
of the cassette, the jumps are two- and three-tooth because
these gears are used for climbing, when you are moving more
slowly and need greater changes with each shift.
Normally, road riders fine-tune gear selection by shifting
the rear derailleur — each rear shift here makes a small difference in pedal effort. For a major change, they shift the front
derailleur to move between chainrings.
The mountain bike has a wider range that is better suited
to the demands of dirt riding, including gravity-defying
ascents and bone-jarring trails. One of the main differences
between the two drivetrains is the third chainring, which is
known as a 'granny' gear (presumably low enough for Granny
to get over hills).You'll also notice that the high end is not
nearly as high as on the road bike — because of the tyre size
and shape and the terrain covered, the speeds achieved off
road are rarely equal to road speeds. Furthermore, the cassette
cog spacing is wider than that of the road bike, so one shift
usually results in at least a two-tooth jump, whether you're
shifting between chainrings or between cogs. This is important because on a mountain bike you're generally not moving
as quickly as on a road bike, and it's best to have a reasonable
gear change with each shift.
Just as road bikers do, mountain bikers usually shift the rear
derailleur for small changes in pedal effort and shift between
chainrings for major changes. Because there are three chainrings, and because off-road terrain can change more abruptly
than pavement, front shifts are more frequent in mountain
biking than in road riding.
Modifying Your Gearing
To fit a gearing system to your particular needs, you need to
determine five things:
4. Chainring and cassette cogs that will combine these
high-low choices with the chosen shift pattern
5. The appropriate derailleurs, shifters and chain to
make your selections work.
If you want to modify your current bike without completely replacing your drivetrain, determine the optimum
high and low gears, decide on a shift pattern, and pick
replacement cogs and chainrings that are compatible with
your derailleurs. Use the tables on pages 308 and 309 to
quickly determine which combinations will give you gears in
the desired range.
On paper, it's possible to invent just about any gear range
and shift sequence. In reality, options are limited. Before
getting too carried away crunching numbers, check with
shops to see what replacement cassette cogs and chainrings
are available for your drivetrain, then plan your gearing
modifications accordingly.
How High?
The 90- to 120-inch high gear found on most bikes represents a kind of gear ceiling that is based on human limitations.
Even the strongest road racers use only slightly larger gears
(maybe 125 or so). In fact, average riders can't maintain a
brisk cadence in a 119-inch gear on a level road; that gear
exists for downhills and tailwinds.
If you're not concerned about the bit of extra speed you'll
lose by coasting downhill instead of pedalling, you can use a
slightly smaller high gear — something in the mid- to upper
90s — and shift down your whole gear pattern to emphasize
the middle and low ranges. It's a trade-off that is commonly
made by mountain bike riders and by touring cyclists who
carry a lot of equipment.
How Low?
1. An optimum high gear
2. An optimum low gear
3. An appropriate shift pattern (jumps between gears)
Recommended low gears
Type of riding
Mountain biking
Loaded touring
Casual road riding
Road racing
Terrain
Gear inches
steep hills
technical trails
dirt roads
steep hills
medium hills
steep hills
medium hills
flat
steep hills
flat to rolling
17-20
17-20
20-27
20-27
32-42
27-37
32-42
37-47
47-60
57-66
Deciding on the optimum lowest gear is a lot more difficult
than choosing the highest. Some factors to consider are your
strength, the steepness and length of the worst hills you usually encounter and the amount of extra weight (if any) you
may carry.You should also take into account the size of gaps
between gears and how much extra difficulty in shifting you'd
be willing to put up with in order to get extra-low gears.
Obviously, lots of personal factors influence your decision
of how low your lowest gear needs to be. Nonetheless, in the
table we make some rough recommendations for those who
don't have a good idea, based on personal experience, of what
the low should be.The recommended gears range from those
suitable for an average to a strong rider within each category.
Thinking in terms of categories is important because an
average racer planning some loaded touring can use a larger
low gear than that recommended for a strong cyclist who's
touring with a heavy load.
GEARS 307
How Many Gears?
The number of gears in your drivetrain won't affect your
choice of high or low gears, but it will affect how many
intermediate gears you have. The 22 or 14 gears provided by
a well-chosen eight-speed cassette and triple or double
crankset will satisfy most riders. (These would actually provide 24 and 16 gears, but remember that you don't use your
two extreme 'crossover' gears.)
Competition road and mountain riders may prefer ninespeed cassettes, which provide one extra cog. The extra gears
can be used on the high or low end or to bridge a too-large
jump between gears. With older five- and six-speed drivetrains (and sometimes even with seven-speeds), racers occasionally find themselves wishing for a gear they didn't have. If
they shift up a gear, it's too easy to pedal; if they shift down,
it's too difficult. With nine cogs, this almost never occurs.
Consequently, nine- and ten-speed cassettes have become
very popular with competitive cyclists both on and off road.
In fact, many century riders find nine- or ten-speed
drivetrains — such as a 12/26 cassette combined with a 39/53
chainring combination — ideal because they provide closely
spaced gears and an adequate high and low.
Likewise, mountain bikers as well as tourists and
commuters carrying loads benefit from the added convenience of a third chainring. Being able to drop down into a
granny gear when the trail steepens or when you're tackling
a tough climb at the end of a long day's ride can make a
significant difference.
Putting It Together
At this point, we should mention that if you need to change
most of the drivetrain components on your bike to get the
kind of gearing you want, it might be more economical to sell
your bike and buy one that has gearing closer to what you
desire. On the other hand, if you're considering starting with
a bare frame and custom-equipping it, the sky's the limit as to
what you can do with the gearing.
Most people's needs can be satisfied with some cassette cog
changes and maybe a new chainring. Those are the cheapest
options. When you start changing cranksets or even adding a
third chainring and making the required bottom bracket axle
change, the costs mount rapidly. Substantial changes in the
range of your bike's gearing may also require new derailleurs.
Be sure to check their gearing capacities before you start.
Generally speaking, if you have to buy a new inner
chainring or a new crankset, it's wise to get a smaller chainring than you think you'll need.You can always match it with
smaller cassette cogs to get big enough gears. If you need
smaller gears, it's a lot easier and cheaper to make further
modifications at the cassette end of your drivetrain than it is
to reorder smaller chainrings.
Your local shop should be able to tell you what size cogs
are available to match your equipment. Make sure that you
order the right type of cog for its particular position on the
cassette. Remember, it may be less expensive and easier to buy
a new cassette with the cogs you want already on it than to
replace more than two cogs on the cassette you already own.
The gearing system on a bicycle makes it possible for
humans to transcend their boundaries of speed and distance
by several quantum leaps. In a nutshell, you are the motor that
drives the bike. In the same way an automobile's motor is
most efficient running at a certain rate (rpm, or revolutions
per minute), your body is most efficient running at a certain
rate, called cadence (for the revolutions per minute you're
pedalling). When you have gearing that's appropriate for your
ability as a cyclist and the terrain you ride in, and you know
how to use the gears, you become incredibly efficient as a
pedaller.
The key is shifting often and correctly, an easy skill to
master. Don't worry about what gear you're in and whether
it's the right or wrong gear. Instead, shift according to feel.You
should have a comfortable cadence you naturally pedal at — a
certain rpm that's most efficient for you. Most cyclists pedal
about 60 rpm when they're just learning to ride and speed up
to 90 as they gain experience. Top racers can fan the pedals
upward of 150 rpm.
To use the gears most efficiently, all you have to do is monitor your pedal speed, something that becomes second nature
in time.When it drops below your comfortable rate, shift into
an easier-to-pedal gear. When you have to pedal too fast, shift
into a harder gear. Your goal is always to be in a gear that
allows you to pedal at a comfortable cadence. With practice,
shifts will become reflexive — you won't even realize you're
doing it. Your shifting skill will make easy work of long and
hilly rides.
To not utilize the full potential of today's easy-shifting,
wide-range gearing systems is to ignore the most significant
advance that has been made in the design and equipment of
the modern bicycle. So even if you're not planning to revamp
your drivetrain, take the time to get to know its strengths and
weaknesses.
308
ILLUSTRATED BICYCLE MAINTENANCE
26-Inch Wheel Gear Chart
56
42.8
44.1
45.5
47
48.5
50.2
52
53.9
56
58.2
60.7
63.3
66.2
69.3
72.8
76.6
80.9
85.6
91
97.1
1 04
112
1 21
1 32
55
42.1
43.3
44.7
46.1
47.7
49.3
51.1
53
55
57.2
59.6
62.2
65
68.1
71.5
75.3
79.4
84.1
89.4
95.3
102
110
119
130
54
41.3
42.5
43.9
45.3
46.8
48.4
50.1
52
54
56.2
58.5
61
63.8
66.9
70.2
73.9
78
82.6
87.8
93.6
1 00
1 08
117
1 28
53
40.5
41.8
43.1
44.5
45.9
47.5
49.2
51
53
55.1
57.4
59.9
62.6
65.6
68.9
72.5
76.6
81.1
86.1
91.9
98.4
1 06
115
1 25
52
39.8
41
42.3
43.6
45.1
46.6
48.3
50.1
52
54.1
56.3
58.8
61.5
64.4
67.6
71.2
75.1
79.5
84.5
90.1
96.6
1 04
113
1 23
51
39
40.2
41.4
42.8
44.2
45.7
47.4
49.1
51
53
55.3
57.7
60.3
63.1
66.3
69.8
73.7
78
82.9
88.4
94.7
1 02
111
1 21
50
38.2
39.4
40.6
41.9
43.3
44.8
46.4
48.1
50
52
54.2
56.5
59.1
61.9
65
68.4
72.2
76.5
81.3
86.7
92.9
1 00
1 08
118
49
37.5
38.6
39.8
41.1
42.5
43.9
45.5
47.2
49
51
53.1
55.4
57.9
60.7
63.7
67.1
70.8
74.9
79.6
84.9
91
98
1 06
116
48
36.7
37.8
39
40.3
41.6
43
44.6
46.2
48
49.9
52
54.3
56.7
59.4
62.4
65.7
69.3
73.4
78
83.2
89.1
96
1 04
113
47
35.9
37
38.2
39.4
40.7
42.1
43.6
45.3
47
48.9
50.9
53.1
55.5
58.2
61.1
64.3
67.9
71.9
76.4
81.5
87.3
94
1 02
111
46
35.2
36.2
37.4
38.6
39.9
41.2
42.7
44.3
46
47.8
49.8
52
54.4
57
59.8
62.9
66.4
70.4
74.8
79.7
85.4
92
99.7
1 09
45
34.4
35.5
36.6
37.7
39
40.3
41.8
43.3
45
46.8
48.8
50.9
53.2
55.7
58.5
61.6
65
68.8
73.1
78
83.6
90
97.5
106
44
33.6
34.7
35.8
36.9
38.1
394
40.9
42.4
44
45.8
47.7
49.7
52
54.5
57.2
60.2
63.6
67.3
71.5
76.3
81.7
88
95.3
1 04
43
32.9
33.9
34.9
36.1
37.3
38.6
39.9
41.4
43
44.7
46.6
48.6
50.8
53.2
55.9
58.8
62.1
65.8
69.9
74.5
79.9
86
93.2
1 02
42
32.1
33.1
34.1
35.2
36.4
37.7
39
40.4
42
43.7
45.5
47.5
49.6
52
54.6
57.5
60.7
64.2
68.3
72.8
78
84
91
99.3
41
31.4
32.3
33.3
34.4
35.5
36.8
38.1
39.5
41
4.6
44.4
46.3
48.5
50.8
53.3
56.1
59.2
62.7
66.6
71.1
76.1
82
88.8
96.9
40
30.6
31.5
32.5
33.5
34.7
35.9
37.1
38.5
40
41.6
43.3
45.2
47.3
49.5
52
54.7
57.8
61.2
65
69.3
74.3
80
86.7
94.5
39
29.8
30.7
31.7
32.7
33.8
35
36.2
37.6
39
40.6
42.3
44.1
46.1
48.3
50.7
53.4
56.3
59.6
63.4
67.6
72.4
78
84.5
92.2
38
29.1
29.9
30.9
31.9
32.9
34.1
35.3
36.6
38
39.5
41.2
43
44.9
47
49.4
52
54.9
58.1
61.8
65.9
70.6
76
82.3
89.8
37
28.3
29.2
30.1
31
32.1
33.2
34.4
35.6
37
38.5
40.1
41.8
43.7
45.8
48.1
50.6
53.4
56.6
60.1
64.1
68.7
74
80.2
87.5
36
27.5
28.4
29.3
30.2
31.2
32.3
33.4
34.7
36
37.4
39
40.7
42.5
44.6
46.8
49.3
52
55.1
58.5
62.4
66.9
72
78
85.1
39.6
41.4
43.3
45.5
47.9
50.6
53.5
56.9
60.7
65
70
75.8
82.7
38.4
40.2
42.1
44.2
46.5
49.1
52
55.3
58.9
63.1
68
73.7
80.4
35
26.8
27.6
28.4
29.4
30.3
31.4
32.5
33.7
35
36.4
37.9
34
26
26.8
27.6
28.5
29.5
30.5
31.6
32.7
34
35.4
36.8
33
25.2
26
26.8
27.7
28.6
29.6
30.6
31.8
33
34.3
35.8
37.3
39
40.9
42.9
45.2
47.7
50.5
53.6
57.2
61.3
66
71.5
78
32
24.5
25.2
26
26.8
27.7
28.7
29.7
30.8
32
33.3
34.7
36.2
37.8
39.6
41.6
43.8
46.2
48.9
52
55.5
59.4
64
69.3
75.6
31
23.7
24.4
25.2
26
26.9
27.8
28.8
29.9
31
32.2
33.6
35
36.6
38.4
40.3
42.4
44.8
47.4
50.4
53.7
57.6
62
67.2
73.3
30
22.9
23.6
24.4
25.2
26
26.9
27.9
28.9
30
31.2
32.5
33.9
35.5
37.1
39
41.1
43.3
45.9
48.8
52
55.7
60
65
70.9
68.5
29
22.2
22.8
23.6
24.3
25.1
26
26.9
27.9
29
30.2
31.4
32.8
34.3
35.9
37.7
39.7
41.9
44.4
47.1
50.3
53.9
58
62.8
28
21.4
22.1
22.8
23.5
24.3
25.1
26
27
28
29.1
30.3
31.7
33.1
347
36.4
38.3
40.4
42.8
45.5
48.5
52
56
60.7
66.2
27
20.6
21.3
21.9
22.6
23.4
24.2
25.1
26
27
28.1
29.3
30.5
31.9
33.4
35.1
36.9
39
41.3
43.9
46.8
50.1
54
58.5
63.8
26
1 9.9
20.5
21.1
21.8
22.5
23.3
241
25
26
27
28.2
29.4
30.7
32.2
33.8
35.6
37.6
39.8
42.3
45.1
48.3
52
56.3
61.5
25
1 9.1
19.7
20.3
21
21.7
22.4
23.2
24.1
25
26
27.1
28.3
29.5
31
32.5
34.2
36.1
38.2
40.6
43.3
46.4
50
54.2
59.1
24
1 8.4
1 8.9
1 9.5
20.1
20.8
21.5
22.3
23.1
24
25
26
27.1
28.4
29.7
31.2
32.8
34.7
36.7
39
41.6
44.6
48
52
56.7
23
1 7.6
18.1
1 8.7
1 9.3
1 9.9
20.6
21.4
22.1
23
23.9
24.9
26
27.2
28.5
29.9
31.5
33.2
35.2
37.4
39.9
42.7
46
49.8
54.4
22
1 6.8
1 7.3
1 7.9
1 8.5
1 9.1
1 9.7
204
21.2
22
22.9
23.8
24.9
26
27.2
28.6
30.1
31.8
33.6
35.8
38.1
40.9
44
47.7
52
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
NUMBER OF TEETH ON REAR COG
These numbers represent "gear inches", which can be used to compare the various combinations of cogs and chainrings. The lower the number, the easier the
gear is to pedal, and vice versa.
FORMULA:
Number of teeth on chain ring
Number of teeth on cog
x Wheel diameter = Gear inches
GEARS 309
27-Inch Wheel Gear Chart
56
44.5
45.8
47.3
48.8
50.4
52.1
54
56
58.2
60.5
63
65.7
68.7
72
75.6
79.6
84
88.9
94.5
1 01
1 08
116
1 26
55
43.7
45
46.4
47.9
49.5
51.2
53
55
57.1
59.4
61.9
64.6
67.5
70.7
74.3
78.2
82.5
87.4
92.8
99
1 06
114
1 24
1 35
54
42.9
44.2
45.6
47
48.6
50,3
52.1
54
56.1
58.3
60.8
63,4
66.3
69.4
72.9
76.7
81
85.8
91.1
97.2
1 04
112
122
1 33
1 37
53
42.1
43.4
44,7
46.2
47.7
49.3
51.1
53
55
57.2
59.6
62.2
65
68.1
71.6
75.3
79.5
84.2
89.4
95.4
1 02
110
119
1 30
52
41.3
42.5
43.9
45.3
46.8
48.4
50.1
52
54
56.2
58.5
61
63.8
66.9
70.2
73.9
78
82.6
87.8
93.6
1 00
1 08
117
1 28
51
40.5
41.7
43
44.4
45.9
47.5
49.2
51
53
55.1
57.4
59.9
62.6
65.6
68.9
72.5
76.5
81
86.1
91.8
98.4
1 06
115
1 25
50
39.7
40.9
42.2
43.5
45
46.6
48.2
50
51.9
54
56.3
58.7
61,4
643
67,5
71,1
75
79.4
84.4
90
96,4
1 04
113
1 23
49
38.9
40.1
41.3
42.7
44.1
45.6
47.3
49
50.9
52.9
55.1
57.5
60.1
63
66.2
69.6
73.5
77.8
82.7
88,2
94.5
1 02
110
1 20
48
38.1
39.3
40.5
41.8
43.2
44.7
46.3
48
49,8
51.8
54
56.3
58.9
61.7
64.8
68.2
72
76.2
81
86.4
92.6
99.7
1 08
118
47
37.3
38.5
39.7
40.9
42.3
43.8
45.3
47
48.8
50.8
52.9
55.2
57.7
60.4
63.5
66.8
70.5
74.6
79.3
84.6
90.6
97.6
1 06
115
46
36.5
37.6
38.8
40.1
41.4
42.8
44.4
46
47.8
49.7
51.8
54
56.5
59.1
62.1
65.4
69
73.1
77.6
82.8
88.7
95.5
1 04
113
110
45
35.7
36.8
38
39.2
40.5
41 .9
43.4
45
46.7
48.6
50.6
52.8
55.2
57.9
60.8
63.9
67.5
71.5
75.9
81
86.8
93.5
1 01
44
34.9
36
37.1
38.3
39.6
41
42.4
44
45.7
47.5
49.5
51.7
54
56.6
59.4
62.5
66
69.9
74.3
79,2
84.9
91.4
99
1 08
43
34.1
35.2
36.3
37.5
38.7
40
41.5
43
44.7
46.4
48.4
50.5
52.8
55,3
58.1
61.1
64.5
68.3
72.6
77.4
82.9
89.3
96.8
1 06
42
33.4
34.4
35.4
36,6
37.8
39.1
40.5
42
43.6
45.4
47.3
49.3
51.5
54
56.7
59.7
63
66.7
70.9
75.6
81
87.2
94.5
1 03
41
32.6
33.5
34.6
35.7
36.9
38.2
39.5
41
42.6
44.3
46.1
48.1
50.3
52.7
55.4
58.3
61.5
65.1
69.2
73.8
79.1
85.2
92.3
1 01
40
31.8
32.7
33.8
34.8
36
37.2
38.6
40
41.5
43.2
45
47
49.1
51.4
54
56.8
60
63.5
67.5
72
77,1
83.1
90
98.2
39
31
31.9
32.9
34
35.1
36,3
37.6
39
40.5
42.1
43.9
45.8
47.9
50.1
52.7
55.4
58.5
61.9
65.8
70.2
75.2
81
87.8
95.7
38
30.2
31.1
32.1
33.1
34.2
35.4
36.6
38
39.5
41
42.8
44.6
46.6
48.9
51.3
54
57
60.4
64.1
68.4
73.3
78.9
85.5
93.3
37
29.4
30.3
31.2
32.2
33.3
34.4
35.7
37
38.4
40
41.6
43.4
45.4
47.6
50
52.6
55.5
58.8
62.4
66.6
71.4
76.8
83.3
90.8
36
28.6
29.5
30.4
31.4
32.4
33.5
34.7
36
37.4
38.9
40.5
42.3
44.2
46.3
48.6
51.2
54
57.2
60.8
64.8
69.4
74.8
81
88.4
35
27.8
28.6
29.5
30.5
31.5
32.6
33.8
35
36.3
37.8
39.4
41.1
43
45
47.3
49.7
52.5
55.6
59.1
63
67.5
72.7
78.8
85.9
83.5
34
27
27.8
28.7
29.6
30.6
31.7
32.8
34
35.3
36.7
38.3
39.9
41.7
43.7
45.9
48.3
51
54
57.4
61.2
65.6
70.6
76.5
33
26.2
27
27.8
28.7
29.7
30.7
31.8
33
34.3
35.6
37.1
38.7
40.5
42.4
44.6
46.9
49.5
52.4
55.7
59.4
63.6
68.5
74.3
81
32
25.4
26,2
27
27.9
28.8
29.8
30.9
32
33.2
34.6
36
37.6
39.3
41.1
43.2
45.5
48
50.8
54
57.6
61.7
66.5
72
78.5
31
24.6
25.4
26.2
27
27.9
28.9
29.9
31
32.2
33.5
34.9
36.4
38
39.9
41.9
44.1
46.5
49.2
52.3
55.8
59.8
64.4
69.8
76.1
30
23.8
24.5
25.3
26.1
27
27.9
28.9
30
31.2
32.4
33.8
35.2
36.8
38.6
40.5
42,6
45
47.6
50.6
54
57.9
62.3
67.5
73.6
29
23
23.7
24.5
25.3
26.1
27
28
29
30.1
31.3
32.6
34
35.6
37.3
39.2
41.2
43.5
46.1
48.9
52.2
55.9
60.2
65.3
71.2
28
22.2
22.9
23.6
24.4
25.2
26.1
27
28
29.1
30.2
31.5
32.9
34.4
36
37.8
39.8
42
44.5
47.3
50.4
54
58.2
63
68.7
27
21.4
22.1
22.8
23.5
24.3
25.1
26
27
28
29.2
30.4
31.7
33.1
34.7
36.5
38.4
40.5
42.9
45.6
48.6
52.1
56.1
60.8
66.3
26
20.6
21.3
21.9
22.6
23.4
24,2
25.1
26
27
28.1
29.3
30.5
31,9
33.4
35.1
36.9
39
41.3
43,9
46.8
50.1
54
58.5
63.8
25
1 9.9
20.5
21.1
21.8
22.5
23.3
24.1
25
26
27
28.1
29.3
30,7
32.1
33.8
35.5
37.5
39.7
42.2
45
48.2
51.9
56.3
61.4
24
1 9.1
1 9.6
20.3
20.9
21.6
22.3
23.1
24
24.9
25.9
27
28.2
29.5
30.9
32.4
34.1
36
38.1
40.5
43.2
46.3
49.8
54
58.9
23
1 8.3
1 8.8
1 9.4
20
20.7
21.4
22.2
23
23.9
24.8
25,9
27
28.2
29.6
31.1
32.7
34.5
36.5
38.8
41.4
44.4
47.8
51.8
56.5
22
1 7.5
18
1 8.6
1 9.2
1 9.8
20.5
21.2
22
22.8
23.8
24.8
25.8
27
28.3
29.7
31.3
33
34.9
37.1
39.6
42.4
45.7
49.5
54
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
NUMBER OF TEETH ON REAR COG
These numbers represent "gear inches", which can be used to compare the various combinations of cogs and chainrings. The lower the number, the easier the
gear is to pedal, and vice versa.
FORMULA:
Number of teeth on chain ring
x Wheel diameter = Gear inches
Number of teeth on cog
310
ILLUSTRATED BICYCLE MAINTENANCE
Glossary
A
ADJUSTABLE CUP: the left-hand cup in a nonsealed bottom bracket,
used in adjusting the bottom bracket bearings, and removed during
bottom bracket overhaul
CABLE END: a small aluminium or plastic cap installed on the ends
AERO LEVERS: road bike brake levers employing hidden cables that
travel out the back of the level body and under the handlebar tape
CAGE: on a front derailleur, a pair of parallel plates that push the
AHEADSET: a type of headset made by Dia-Compe that fits on a
of brake and shift cables to keep them from fraying; also known as
a cable crimp
chain from side to side; on a rear derailleur, a set of plates in which
pulleys are mounted to hold and guide the chain from cog to cog
fork that has a nonthreaded steerer
CALIPERS: (1) brake arms that reach around the sides of a wheel to
ALLEN WRENCH: a specific brand of hex key
press brake pads against the wheel rim; (2) the fixed portion of a
disc brake system that houses the pistons and brake pads
ALL-MOUNTAIN BIKE: a mountain bike designed to balance
climbing and descending abilities with slightly more emphasis
on descending prowess; features dual-suspension with 10 to 15 cm
(4 to 6 inches) of travel
CANTILEVER BRAKES: rim brakes with pivoting arms mounted on
fork blades or seatstays
CASSETTE HUB: a type of rear hub that has a built-in freewheel
mechanism
ALL-TERRAIN BIKE (ATB): a term sometimes used for
mountain bike
CHAIN: the series of links pinned together that extends from the
B
chainring to the cogs on the back wheel and allows you to propel
the bike by pedalling
BAR-ENDS: mini handlebar add-ons that fit on the ends of
mountain bike bars to add another riding position
BEACH CRUISER: a bike that is designed for casual and comfortable
road riding and that features a relaxed frame, fat 26-inch tyres, a
wide saddle, a wide handlebar and rubber pedals
BICYCLE MOTO CROSS (BMX): a type of racing done on a closed
dirt track over obstacles, usually on 20- or 24-inch-wheel bikes
with one gear
BINDER BOLT: the bolt used to fasten a stem inside a steerer tube, a
seatpost inside a seat tube or a handlebar inside a stem
BMX: see Bicycle Moto Cross
BOTTOM BRACKET: the cylindrical part of a bicycle frame that holds
CHAINRING: a sprocket fixed to the right crankarm to drive the chain
CHAINRING NUT SPANNER: a special tool used to loosen the slotted
chainring bolts (the ones behind the inner ring) that fasten a
chainring to a crankarm
CHAINSTAYS: the two tubes of a bicycle frame that run from the
bottom bracket back to the rear dropouts
CHAINWHEEL: see Chainring
CHAIN WHIP: a tool consisting of a metal bar and two sections
of chain, used in changing cogs on a cassette; also known as a
chain spanner
CHROME-MOLY: a type of high-quality steel tubing; also known as
chrome molybdenum or cro-mo
the crankset axle, two sets of ball bearings, a fixed cup and an
adjustable cup
CLINCHER TYRE: a tyre with edges that hook under the curved-in
BRAKE PAD: (1) a block of rubberlike material fastened to the end
of a rim-brake caliper; it presses against the wheel rim when the
brakes are applied, also known as a brake block; (2) a thin block of
resin, organic or metallic-compound material that is clamped onto
the disc (of a disc brake system) by the caliper
CLIPLESS PEDALS: pedals that use a releasable mechanism like that
of a ski binding to lock onto cleated shoes and do not use toeclips
or toe straps
BRAKE SHOE: the metal part that holds a brake pad and is bolted to
the end of a brake caliper
BRAZE-ONS: parts for mounting shift levers, derailleurs, water bottle
cages and racks, which are fastened to a bicycle frame through a
type of soldering process known as brazing
BRINELLED: a type of wear in bearing components that is a series of
dents in the races or cups
BUSHING: a sleeve that fits between two parts to act as a bearing,
edge of a rim
COASTER BRAKE: a foot-operated brake built into the rear hub;
normally found on one-speed kids' bikes and cruisers
COG: a sprocket that is attached directly to the rear hub on a
single-speed bike and mounted on a cassette on a multispeed bike
CONE: a bearing race that curves to the inside of a circle of ball
bearings and works in conjunction with a cup
CORNCOB: a term used to describe a cluster of cogs on a racing
cassette because of the small variation in number of teeth on
adjacent cogs
often found in suspension systems
COTTERED CRANKSET: a crankset in which the crankarms are
fastened to the axle by means of threaded cotters and nuts
BUTTED TUBING: tubing with an outside diameter that remains
constant but with a thinner-walled midsection where less
strength is needed
COTTERLESS CRANKSET: a crankset in which the crankarms are
fastened to the axle by means of a taper and nuts or bolts
(instead of cotters)
GLOSSARY 311
CRANKARM: a part, one end of which is attached to the bottom
bracket axle and the other of which holds a pedal, that, through its
forward rotation, provides the leverage needed to power the bicycle
CRANKARM BOLT: the bolt that holds a crankarm onto the end of
the axle in a cotterless crankset
CRANKSET: the bottom bracket, two crankarms and one or more
chainrings of a bike
CROSS-COUNTRY BIKE: a mountain bike suited to racing on
varied terrain; features include wide-range gearing with super lows,
sometimes with short travel (3 inches or less) dual-suspension,
great brakes and a light performance-oriented frame
CROSSOVER CABLE: see Stirrup cable
CRUISER: see Beach cruiser
C-SPANNER: a spanner with a C-shaped end that is used to loosen
the lockring on certain bottom brackets and headsets
CYCLO-CROSS BIKE: a bicycle designed specifically for cyclo-cross
racing, an event where lightweight bicycles that resemble road bikes
are raced on an off-road course that includes sections where the
rider must dismount and run with the bike; features include specific
geometry, drop handlebars, knobby tyres and cantilever brakes
D
DAMPING: the process of controlling suspension action, without
which a suspended fork would bounce like a pogo stick
DERAILLEUR: a lever-activated mechanism that pushes the chain off
of one sprocket and onto another, thus changing the gear ratio
DERAILLEUR HANGER: a threaded metal piece that extends below
the right rear dropout and is used as a mount for the rear derailleur
DIAMOND FRAME: the traditional men's bicycle frame, the principal
parts of which form a diamond shape
DIRECT-PULL BRAKE: a type of very powerful centrepull brake used
mostly on mountain bikes from the 1980s and early 1990s
DISC BRAKE: a braking system that uses a small caliper mounted
near a front or rear dropout (usually on the left side) that clamps onto
a stainless steel disc attached to the hub to generate braking force
DISH: on a multispeed bike with a cassette or freewheel, the rear
wheel's hub is located off centre (to provide room for the cogs); to
ensure that the rim aligns in the frame, the rim is centred over the
axle instead of the hub, which means that the right-side spokes are
more tightly tensioned and more steeply angled than the left-side
spokes, a condition known as 'dish'
DOWNHILL BIKE: a bike designed for racing down mountains;
features include long-travel 15 cm (6 inches or more) dual-suspension
frame, great brakes, single chainring, long saddle and a riser handlebar
DOWN TUBE: the frame tube running from the headset to the
bottom bracket; one part of the main triangle on a bicycle frame
DOWN-TUBE SHIFT LEVERS: shift levers mounted to the down tube
DRAFTING: tucking in closely behind another rider so he'll take the
full force of the wind, saving you energy
D-RING: a D-shaped ring that is found on some models of shift
levers and is used to adjust the level of tension on the inner
parts of the lever
DRIVETRAIN: the derailleurs, chain, freewheel and crankset
DROP: the vertical distance from the horizontal line connecting the
two wheel axles and the bottom bracket; one way of determining
the location of the bottom bracket in relation to the rest of the
bicycle frame; sometimes referred to as b/b drop or bottom
bracket drop
DROPOUT: slots in the frame and fork into which the rear and
front wheel axles fit
DROPS: the lower straight portions of a turned-down-type
handlebar
DUAL-CROWN FORK: a type of suspension fork that resembles a
motorcycle fork due to crowns above and below the head tube,
which increase stiffness
DUAL-SUSPENSION BIKE: a bike with front and rear suspension; also
known as a 'clualie'
DUSTCAP: a metal or plastic cap that fits into a hub shell to keep
contaminants out of hub bearings; or a metal or plastic end cover
for an axle in a pedal or a cotterless crankset
E
ELASTOMER: a material, usually urethane, that is used in suspensions
to provide shock absorption and damping, and that is favoured due
to its low cost and simple maintenance requirements
END PLUGS: the caps that fit onto or into the ends of the
handlebars
ENDURO BIKE: a mountain bike for cross-country endurance races;
generally lightweight, mid-travel (3 to 4 inches) dual-suspension
designs to balance performance and long-ride comfort
ERGOPOWER LEVERS: the name for Campagnolo's shifting
brake levers
F
FACE: to shave the outer edges of a bottom bracket shell or the
upper and lower ends of a head tube to make them parallel with
one another and square to the tube's centreline so that, when the
bottom bracket or headset is installed, the bearings will run as
smoothly as possible
FERRULES: removable cylindrical metal or plastic caps used to
reinforce the ends of cable housing
FIXED CUP: the right-hand cup in a bottom bracket
FIXED GEAR (WHEEL): as found on track-racing road bikes, a
hub-and-cog combination that's designed in such a way that
one must always pedal; it's impossible to coast
FIXING BOLT: a bolt used to hold a crankarm on an axle in a
cotterless crankset
FLANGE: the part of a hub shell to which spokes are attached
FORK: the part of the frame that fits inside the head tube and holds
the front wheel; a term also sometimes applied to the part of the
frame where chainstays and seatstays join to hold the rear axle
FORK BLADES: the parallel, usually curved tubes that hold the
front wheel
312
ILLUSTRATED BICYCLE MAINTENANCE
FORK CROWN: the horizontal piece on the upper part of the front
fork to which the fork blades attach
FORK RAKE: the shortest distance between the front axle and
an imaginary line extending through the head tube down towards
the ground
FORK TIPS:
the slotted tips of the fork blades into which the front
HYDRAULIC BRAKE:
a brake relying on a sealed fluid system instead
of a cable for operation
HYSTERESIS:
the damping provided by elastomer spring
wheel axle fits; also called dropouts
I DLER PULLEY: the pulley in a rear derailleur that stays furthest from
the cassette cogs and keeps tension on the chain
FREERIDE BIKE:
a type of mountain bike designed to ride the most
technical and punishing of downhill trails; features include longtravel (6 to 8 inches) dual-suspension and components manufactured for ultimate strength
I NDEX SHIFTERS: levers that 'click' into distinct positions that
correspond to certain cassette cogs and don't require fine-tuning
after each shift
FREEWHEEL: a removable component on the rear hub that carries
gear cogs on the outside and contains a ratcheting mechanism
inside that provides the connection to the wheel for pedalling
while also allowing coasting; sometimes used to refer to the ratcheting mechanism inside a cassette
J
FRICTION SHIFTERS: conventional (nonindex) levers that retain their
position through the use of friction washers
K
FRONT FORK: Fork
KNOBBY TYRES: heavy-duty tyres with large rubber knobs spaced
relatively far apart to provide traction in off-road terrain
a quadrilateral with one short side, it is the section of a bicycle frame that consists of the head tube, top tube, seat
tube and down tube
FRONT TRIANGLE:
LADIES' FRAME: the type of frame in which the top tube is replaced
by a second down tube to make mounting and dismounting easier
G
GEAR:
the pulley in a rear derailleur that stays closest to
the cogs and guides the chain from cog to cog during a gear shift;
sometimes called the guide pulley
JOCKEY PULLEY:
one position on a dr vetrain; for example, being on the
larges
GRANNY:
slang for the tiny inner chainring on a triple-chainring
crankset
the rubber or foam sleeves that fit on the ends of upright
handlebars; you grip them when riding
GRIPS:
GUIDE PULLEY: see Jockey pulley
H
HALF-STEP GEARING: a gearing system in which a shift between
chainrings in a double-chainring set is equivalent to half a gear
step on the freewheel
the combination of cups, cones and ball bearings that
creates the bearing mechanism that allows the fork column to
rotate inside the head tube so you can steer
HEADSET:
the shortest tube in the main triangle, it is the one in
which the fork column rotates
HEAD TUBE:
HEX KEY: a
small L-shaped hexagonal spanner that fits inside the
head of a bolt or screw; sometimes referred to as an Allen key or an
Allen wrench
HOUSING:
the plastic-covered tubing inside which the cables run
the centre of a wheel, consisting of a shell to which spokes
attach and containing an axle along with two sets of bearings,
bearing cones, lockwashers, locknuts and parts for attaching the
wheel to the frame
HUB:
any type of brake (such as disc, drum or coaster)
that operates through the wheel hub rather than through
the rim
HUB BRAKE:
LEFT-HAND THREADING: threading that's the opposite of regular
threading, meaning you must turn to the left to tighten and to the
right to loosen; always found on a bicycle's left pedal; also known as
reverse threading
LINKING CABLE: see Stirrup cable
LOADED TOURER: a bicycle with structural strength, geometry and
equipment that is designed to allow a cyclist to travel with a full
load of gear
LOCKNUT: a nut used along with a washer or a second nut to lock a
mechanism in place, such as the nut at the upper end of a headset
or the nut in front of the calipers on some caliper brakes
LOCKRING: the notched ring that fits on the left side of some
bottom brackets and prevents the adjustable cup from turning
LOCKWASHER: a washer with a small metal tab to prevent it from
turning, such as the washer beneath the locknut on a headset or
between the locknut and cone on a hub
LOOSE BALL BEARINGS: bearings inside a component that are not
held in a metal or plastic retainer
LUG: an external metal sleeve that holds two or more tubes
together at the joints of a frame
M
MAIN TRIANGLE: see Front triangle
MASTER LINK: a special link on a bicycle chain that can be opened
by flexing a plate, removing a screw or some other means besides
driving out a pin
a frame that replaces the top tube with twin lateral
tubes that run from the head tube back to the rear dropouts
MIXTE FRAME:
GLOSSARY 313
MOUNTAIN BIKE: a bicycle with a straight handlebar, sturdy fat tyres
and wide-range gearing designed for off-road use
MOUNTING BOLT: see Pivot bolt
N
NEXUS: a type of Shimano hub that has four or seven internal gears
and an internal brake
NIPPLE: a small metal piece that fits through a wheel rim and is
threaded inside to receive the end of a spoke
NOODLE: the L-shaped tubing piece found on the side of Shimano
V-Brakes and some other direct-pull cantilevers
P
PANNIERS: luggage bags used in pairs and fastened alongside one or
both wheels of a bike
RECUMBENT: bikes that place the rider in a reclining position
REGULAR THREADING: the threading that's found on almost all bike
parts; turn to the right to tighten and to the left to loosen
REVERSE THREADING: see Left-hand threading
REPLACEABLE DERAILLEUR HANGER: a type of derailleur hanger that
can be easily replaced using hand tools if it gets damaged
RETAINER: a metal or plastic ring that holds the bearings in place in
a headset, bottom bracket or sometimes a hub
RIM: the metal hoop of a wheel that holds the tyre, the tube and
the outer ends of the spokes
RIM BRAKE: any type of brake that slows or stops a wheel by
pressing its pads against the sides of the wheel rim
RISER HANDLEBAR: a mountain bike handlebar that bends up on
the ends; found on downhill, freeride and some cross-country bikes
PIN SPANNER: a spanner with pins on forked ends that is used to
turn certain adjustable cups on some bottom brackets
ROLLERCAM BRAKES: mountain bike brakes that affix to frame posts
and employ a cam-and-pulley system to modify pressure on the
ri ms
PIVOT BOLT: a bolt on which the arms of caliper brakes pivot and
which also serves as the means for mounting the brakes on the
frame
ROLLERS: a stationary training device with a boxlike frame and
three rotating cylinders (one for the front wheel and two for the
rear wheel) on which the bicycle is balanced and ridden
PLAIN GAUGE TUBING: tubing of a thickness that remains constant
over its entire length
S
POTATO CHIPPED WHEEL: see Taco'd wheel
PRELOAD: an important suspension adjustment that usually involves
modifying pressure or adjusting the elastomers to ensure that the
suspension responds appropriately to the rider's weight
PRESTA VALVE: a bicycle tube valve with a stem that has a small nut
on top that must be loosened during inflation, instead of a spring
such as is found on a Schrader valve
Q
QUICK LINK: a special connecting link that allows derailleur-type
chains to be disassembled and reassembled without the use of tools
QUICK-RELEASE: a cam-lever mechanism used to rapidly tighten or
loosen a wheel on a bike frame, a seatpost in a seat tube or a brake
cable within cable housing
QUICK-RELEASE SKEWER: a thin rod that runs through the centre of
a wheel axle; a cam lever is attached to one end, and the other end
is threaded to receive a nut
QUILL: similar to the rattrap type of pedal except that the two sides
of the pedal frame are joined by a piece of metal that loops around
the dustcap
R
RACES: curved metal surfaces of cups and cones that ball bearings
contact as they roll
RAKE: see Fork rake
RATTRAP: a type of pedal that has thin metal plates with jagged
edges running parallel on each side of the pedal spindle
REAR TRIANGLE: a frame triangle formed by the chainstays, seatstays
and seat tube
SADDLE: the seat on a bicycle
SCHRADER VALVE: a tyre valve similar to the type found on
automobile tyres
SEALED BEARINGS: bearings fastened in sealed containers to keep
out contaminants
SEALED PULLEY: a type of derailleur pulley that has sealed bearings
SEAMED TUBING: tubing made from steel strip stock that is curved
until its edges meet, then welded together
SEAMLESS TUBING: tubing made from blocks of steel that are
pierced and drawn into tube shape
SEAT CLUSTER: the conjunction of top tube, seat tube and seatstays
near the top of the seat tube
SEATPOST: the part to which the saddle clamps and which runs
down inside the seat tube
SEATSTAYS: parallel tubes that run from the top of the seat tube
back to the rear axle
SEAT TUBE: the tube that runs from just below the saddle down to
the bottom bracket
SEMISLICK TYRE: a type of mountain bike tyre with limited tread;
popular for not-too-technical courses because it rolls faster than
a knobby tyre
SEW-UP: see Tubular
SHALLOW ANGLES: angles that position frame tubes further from
vertical and closer to horizontal; also known as slack angles
SKIPPING: a popping feeling in the drivetrain when you pedal
hard; it occurs when a cog is worn out and when you install a
new chain on worn cogs
SLACK ANGLES: see Shallow angles
314
ILLUSTRATED BICYCLE MAINTENANCE
SOLVENT: a liquid used to cut grease and grime
SPIDER: the multiarmed piece to which the chainwheels are bolted;
usually welded to or part of the right crankarm
SPINDLE: another term for an axle (such as a pedal axle or a
TOP TUBE: the horizontal tube that connects the seat tube with the
head tube
TOURIST: a cyclist who takes excursions by bicycle, often carrying
several panniers containing clothing and camping equipment
bottom bracket axle)
TRACK BIKE: a type of bike used for racing on a bicycle track (velo-
SPOKE: one of several wires used to hold the hub in the centre of a
drome); looks a lot like a road bike but features only one gear and
has no brakes
wheel rim and to transfer the load from the perimeter of the wheel
to the hub and onto the frame
SPORTS TOURER: a
bicycle with structural strength, geometry and
components designed to make it a compromise between a bike
suitable for racing and one suitable for loaded touring; good for
general pleasure riding
SPROCKET: a disc bearing teeth for driving a chain; a general term
that applies both to chainrings and to cassette cogs
TRANSVERSE CABLE: see Stirrup cable
TRIALS: a mountain bike competition that tests riders' abilities to
negotiate large obstacles such as boulders, logs and parked cars;
these competitions are judged on technical ability rather than speed
TRIPLE CRANK: a triple-chainring crankset designed to provide a
wide range of gears
TUBULAR: a type of tyre that has a tube sewn inside the casing; also
STAINLESS STEEL: a type of steel that will not rust; ideal for spokes
known as a sew-up
STATIONARY TRAINER: device you attach your bike to so you can
TWIST SHIFTER: a type of shift lever that's twisted to shift the gears,
ride in place
such as Grip Shift models.
STEEP ANGLES: angles that position frame tubes nearer to vertical
than do shallow angles
U
STEERER TUBE: the tube that forms the top of the fork and rotates
U-BRAKES: heavy-duty centrepull mountain bike brakes that affix to
inside the head tube
frame posts
STEM: the part that fits into or on the fork and holds the handlebar
UCI (UNION CYCLISTE INTERNATIONALE): international governing
body of professional and amateur bicycle racing
STI: Shimano's name for its shifting brake levers
STIRRUP CABLE: on centrepull-type brakes, a short cable, each end
of which attaches to a brake arm and which is pulled up at the
centre to activate the brakes; also known as straddle cable
SUSPENSION: as found on all cars, most mountain bikes and some
road- and casual- bike models, forks and frames that absorb road
and trail shocks to improve comfort and control
SWINGARM: the movable rear end of a suspended bicycle
U-LOCK: a U-shaped lock; sometimes called a D-lock
UNICROWN FORK: a fork (usually on mountain bikes) on which
the blades curve in at the top and are welded directly to the steerer
instead of fitting into a fork crown
UNIVERSAL CABLE: a shift or brake cable that's designed to fit all
types of levers; on each end is a different lead end, and you cut off
the one you don't need
V
TACO'D WHEEL: a wheel that's been bent so severely that it curls
back on itself and resembles a hard taco
V-BRAKE: Shimano's brand name for their model of direct-pull
brake
TANDEM: a bicycle that has seats, bars and pedals for two or more
riders, one behind the other
TAP: to cut threads inside a tube or opening; also the name of the
tool that does the cutting
THREADLESS HEADSET: a type of headset that fits on a fork with a
WHEELBASE: the distance between the front and rear axles
Y
threadless steerer; often found on mountain bikes
YOKE: a triangular metal piece used to connect the main brake
THREAD LOCKING COMPOUND: a liquid applied to threads to
cable with the stirrup cable in a centrepull brake system; also
known as a pickup
ensure that the part stays tight after it's attached
THREE-CROSS: a spoking pattern in which a spoke passes over two
and under a third spoke before being attached to the rim
THUMB SHIFTER: a shifter designed to be operated with the thumbs,
such as Shimano Rapid Fire models or Sturmey Archer three-speed
models
TOECLIPS AND TOE STRAPS: a cagelike kit attached to pedals to
keep your feet in the correct position (unnecessary on clipless pedals)
ZIP-TIE: a plastic strap that, when threaded through its end and
pulled, tightens and stays tight to affix cables or number plates
to a bicycle
RESOURCES 315
Resources
CYCLE MANUFACTURERS
BIANCHI
www.bianchi.it
BROMPTON BICYCLES (FOLDING BIKES)
www.bromptonbicycle.co.uk
CANNONDALE
www.cannondale.com
GIANT BICYCLES
NETTI
ww.netti.com.au
www.speedplay.com
NIKE
www.nike.com
wwwsram.com
SPEEDPLAY PEDALS
SRAM
PANDA SPORTSWEAR
www.pandasport.co.za
BIKE FITTING SERVICE
PEARL IZUMI CLOTHING
www.pearlizumi.com
FIT KIT
www.bikefitkit.com
www.giant-bicycles.corn
SIDI SHOES
KONA MOUNTAIN BIKES
www.konaworld.com
www.sidisport.com
MAIL ORDER AND INTERNET SHOPS
LEMOND BICYCLES
TOOLS AND COMPONENTS
www.bicycles.net.au
WN\ .1e111011dblkeS.00111
ABUS LOCKS
CECIL WALKER CYCLES (AUSTRALIA)
LITESPEED TITANIUM BICYCLES
www.abus.com
www.litespeed.com
BONTRAGER
www.bontrager.corn
www.cecilwalker.com.au
+61 (0)3 6900 9000
MARIN MOUNTAIN BIKES
www.marinbikes.com
MERLIN
www.merlinbike.com
BICYCLES NETWORK AUSTRALIA
CAMPAGNOLO
KAYALAMI PRO CYCLES (SOUTH AFRICA)
www.kayalamicycles.co.za
+27 11 9072466
www.campagnolo.com
CATEYE COMPUTERS AND LIGHTING
PARKER INTERNATIONAL (UK)
www.parker-international.co.uk
www.cateye.com
+44 (0)870 0660340
CINELLI HANDLEBARS
WIGGLE (UK)
QUINTANA ROO
www.rooworld.com
www.cinelli.it
www.wiggle.co.uk
SEROTTA
www.serotta.com
www.conti-online.com
NATIONAL CYCLING BODIES
EASTON
SPECIALIZED
www.specialized.com
AUSTRALIAN CYCLING FEDERATION
www.eastonbike.com
www.cycling.org.au
FINISHLINE LUBES
www.finishlineusa.com
www.bcf.uk.com
OMEGA TITANIUM
www.omegacycleworks.co.uk
TREK
www.trekbikes.corn
CLOTHING, SHOES, HELMETS
ASSOS CLOTHING
www.assos.com
BELL HELMETS
www.bellbikehelmets.com
CARNAC SHOES
www.carnacsport.com
CASTELLI CLOTHING
www.castellisport.it
CONTINENTAL TYRES
HUTCHINSON TYRES
www.hutchinson.fr
LOOK PEDALS
SOUTH AFRICAN CYCLING FEDERATION
www.sacf.co.za
MAGURA SUSPENSION AND DISC BRAKES
www.magura.com
MAVIC
WWW.mavic.corn
PARK TOOLS
www.parktool.com
RITCHEY
www.ritcheylogic.com
GIRO HELMETS
ROCK SHOX SUSPENSION
www.rockshox.com
I MPSPORT CLOTHING
www.impsport.com
MET HELMETS
www.met-helmets.corn
CYCLING NEW ZEALAND
www.cyclingnz.com
www.lookcycle. corn
GIORDANA CLOTHING
www.giordana.com
www.giro.com
BRITISH CYCLING
SELLE ITALIA SADDLES
www.selleitalia.com
SHIMANO
www.shimano.com
316
ILLUSTRATED BICYCLE MAINTENANCE
Index
Page numbers in italics refer to
illustrations
A
aero brake levers 223,225,238-9,
238-9
alcohol 20
aluminium 31,36
axles 87-9,105
diameter 52-3
quick-release 52,53
through 87-9
B
ball–tipped hex key set 16
bearings:
bottom bracket 111,117,119
hub, lubricating 101,101
pedal 292
Look, overhaul 300-1,300-1
Shimano SPD, overhaul 296-7,
296-7
biodegradable cleaning products 20
BMX bikes 145
bottom brackets 103-6,105
cartridge-style, installing 109-10,
126-7,126-7
cup-and-cone:
adjusting 111-12
installing 111-12
overhauling 110-11
tapping and facing 110-11
external 105,106,107
height 32
identifying type 106
maintenance 18
overhauling 108,109,110-11,116-21,
116-21
spline interfaces 105-6
threading 106,107
boxing a bike 24-5,24-5
brake booster 228-9
brake cables see cables
brake jack 41
brake levers:
adjustment 232,232
aero 223,225
installing 238-9,238-9
conventional (non-aero) 223,224
installing 223-4
mountain 224
installing 237,237
positioning 224
removing 223-4,232,232
brake pads:
adjustment 228
cleaning 20
maintenance 18,254-5,254-5
sticking 228
brake-shift levers 155,157,157, 160
installing 166-7,166-7
brakes 217-55
see also cables
adjustment 228
attaching cables 226
attaching discs 219
breakdowns 229
buying 223
cable housing 222-3,225-6,225
cantilever 56,222,223,224,226-7,
228
installing and adjusting 250-1,
250-1
centrepull 222,226-7,228
centring 227-8
cleaning 20
coaster 217
direct-pull 222,223,224,227
adjustment 252-3,252-3
disc 56,217
aligning calipers 220-2
hydraulic 217-20
bleeding 220
installation and setup 246-9,
246-9
maintenance 242-3,242-3
mechanical 220-2
installation and setup 244-5,244-5
mounting disc 220
rotors 221
troubleshooting 229-30
drum 217
hub brakes 217
installing 224-6
maintenance 219,229
opening 56
rim brakes 217,222
sidepull 56,218, 222,223,224,227-8
installing 240-1,240-1
sizes 223
squealing 228-9
troubleshooting 229-31
types 217
V–brake 222
adjustment 252-3,252-3
brinelling 206
brushes 20
C
cable housings 222-3
installing 225,225
sizing 225-6
cables:
adjustment 189-90
attaching to brakes 226
installing 225,233-6,233-6, 237,237,
238-9,238-9
lubricating 22
protection 229
stretching 228
carbon 31,36
cassette lockring tools 16
cassettes 132,132
cleaning 132
lubricating 132
maintenance 136,138-9,138-9
removal 140-1,140-1
removing cogs 134-5
troubleshooting 136-7
worn cogs 147
caulk 35
chain tools 148,149
chainring changer 174
chainrings:
cleaning 20,109
double 173
gang 104
I NDEX 317
lubricating 21
maintenance 124-5,124-5
removing 112
sizes 107,131
straightening 112,124,124
triple 173
chains 145-53
adjustment 189-90
checking 147
cleaning 20,21,149-50
construction 146
identification 145
installing 22
length 147-8
lubricating 21-2,149-50
maintenance 152-3,152-3
reassembling 150
repairing 152-3,152-3
separating 148-9,148, 149, 152,152
servicing 145-8
size 145
skipping 147
squeaking 150
stiff links 147,150,150
troubleshooting 151
width 145
worn 145-6
chainstays 27
length 32
protectors for 35
chainsuck 147
chainwhip 16
children's bikes 217
cleaning:
materials for 18-20
routine 18
cleats 290-1
adjustment 291
coaster brake bikes, chains 148
coaster brakes 217
cogs:
cogsets 135
disassembly 141,141
removing 134-5,143,143
replacement 143,143
size 131
worn 147
combination spanners 17
composites, for frames 31
cone wrench 16
corrosion 34-5
cotters, removing 108
crankarm puller 16
crankarms:
adjustment 114-15,114-15
installing 112
length 107-8
removing 108-9
removing cotters 108
cranksets 103-29
Ashtabula (one-piece) 103
changing 106-8
construction 103
tottered 103,112
cotterless 103,103, 105, 112
installing 122-3,122-3, 129,129
maintenance 112-13
overhauling 108-9
removal 122,122,128-9, 128-9
Shimano Octalink, removal and
installation 122-3,122-3
troubleshooting 113
two-piece, removal and installation
128-9,128-9
types 103
cruiser saddles 277
cutting oil 18
cycling shoes 287,289
cycling shorts 278
cyclocross 34
D
damping 39-41
degreasers 20
derailleur cages 187-8,189
derailleur chains 145,148-9,149
derailleur hangers 188,189
damage to 35-6
derailleurs 52
front 173-83
adjustment 176,182-3,182-3
installing 179-81,179-81
maintenance 175-6,177-8,177-8
selecting 175
technology 173-5
troubleshooting 176
types 173
rear 185-97,187
accessories 191
adjustment 190-1,196-7,196-7
anatomy 186,187-8
cleaning 189,194,194
double–pivot 187,188
index barrel adjustment 190-1
installing 190,193,193
lubrication 189,195,195
maintenance 189
modifications 191
mounting 188-9
removal 192-3,192-3
replacing 185-7
selecting 188
single-pivot 187-8
technology 187-8
troubleshooting 191
types 185-7,185
shift levers 155
diagonal cutter 16
disc brakes 56,217
aligning calipers 220-2
hydraulic 217-20
bleeding 220
installation and setup 246-9,246-9
maintenance 242-3,242-3
mechanical 220-2
installation and setup 244-5,244-5
mounting disc 220
rim, troubleshooting 230-1
rotors 221
troubleshooting 229-30
downhill bikes 34,43-4,54,87
drivetrains:
fixed 131,217
floating 42-3,43
index 305
dropouts 52,53
drum brakes 217
E
elastomers 39,45,47
Enduro bike 34
F
facing tools 17
Fit Kit 291
float 291
floating drivetrain 42-3,43
318
ILLUSTRATED BICYCLE MAINTENANCE
forks 27
lubricating 21
maintenance 41
suspension 39-41,40, 41, 42
width 37
four-bar linkage 42,43
frame-alignment tables 17
frames 27-37
alignment checks 36-7
anatomy 27-9,28
bent 35
geometry 27-9,30,31-4
history 29-30
ladies' 29-30,30
maintenance 34-6
materials 30-1
men's 29,30
mixte 29,30,30
repainting 37
tube types 32
waxing 36
freeride bikes 34,43-4,54,87
freewheel removers 133
freewheels 53-4,131-43
cassette 132,132
cleaning 132
cog removal and replacement 143,
143
installing 136
lubricating 132
maintenance 138-9,138-9
removing 133-4,142,142
replacing 142,142
troubleshooting 136-7
gearing:
charts 305,308-9
modifying 306
theory 303-5
gears 303-9
see also shift levers
cassette 53-4
high 306
low 306
number of 307
patterns 305
ratios 303
shifting 303,305-6,307
sizes 303
testing 56
gloves 20
grease (lubricant) 20-1
`green' cleaners 20
H
handlebar grips, installing 263,273,273
handlebar stems see stems
handlebars 257-73
adjusting 263-4,265-7,265-7, 285,
285
anatomy 258
compatibility with stem 259-60
installing 261-2,269,269, 272-3,272-3
padding 262
removing 268-9,268-9
selecting 260-1
size 260
taping 262-3,270-1,270-1
troubleshooting 264
types 260
head angle 27-32
headset wrench 16
headsets 199-215
adjustment 202-3,205, 206,208-9,
208-9,214, 214
anatomy 200, 201
buying 201-2
cleaning 18
cup-and-cone 202
double locknuts 203
fitting 206
function 199
integrated 201,201, 202
maintenance 18
overhaul 203-6,203, 210-13,210-13,
215,215
reassembling 204-6
sealed-bearing 199,201-2
seals 202
sizes 199,202
threaded 201,202-3,204-5,206
adjustment 208-9,208-9
overhaul 210-13,210-13
threadless 201,202,204-5
adjustment and overhaul 214-15,
214-15
top caps 205-6
troubleshooting 207
types 199-201,199
hex key set 16
high-forward pivot 42,43
high-wheelers 131,303
highly coupled linkage 42,43
hook spanner 16
hub brakes, types 217
hubs 49,87-101
adjustment 89-90,89, 92-3,92-3,
98-100,98-100
bearings, lubricating 101,101
Campagnolo, overhauling and
adjusting 98-100,98-100
cassette 90-1,136
cleaning 18
cone-and-locknut type:
adjusting 92-3,92-3
overhaul 94-7,94-7
construction 87-9,87, 88
freewheel 90-1
maintenance 18
new, shopping for 90-1
overhaul 90,94-7,94-7, 98-100,98–
100
quick-release 89, 90
size 52
solid-axle 87
through-axle 87-9,87
tips 90
troubleshooting 91
width 52,53, 91
hybrid bikes 34,287
hydraulics 217-19
I
injuries 22-3
inner tubes see tubes
J
jump bike 34
I
ladies' frame 29-30,30
loaded touring bike:
brakes 222
frame geometry 33
I NDEX 319
locknuts 203
lockring tools 16
low pivot 42, 43
lubricants 20-2, 149-50
recommended 23
lubrication 18
M
maintenance:
basic principles 23
preventive 18-22
schedule 22
men's frame 29, 30
mini-tools 20
mixte frame 29, 30, 30
mountain bikes 34
brake levers 224
installing 237, 237
brakes 217, 222
cable housing 225
cable installation 237, 237
chainsuck 147
crankarms 108, 112
derailleurs 175, 185, 185
frame geometry 32, 33-4
gears 305, 306, 307
handlebar grips, installing 263, 273,
273
handlebars 259, 260, 261
adjusting 264
pedals 287, 289, 291
maintenance 294-5, 294-5
seatposts 279
shift levers 155, 157, 158, 158, 159,
168-70, 168-70
spoke protectors 191
stems 257
installing 272-3, 272-3
tyres 49, 55
wheels 54
multi-tools 20
N
needlenose pliers 16
O
oils 21-2
P
paint protection 35
paintwork 37
pedal wrenches 16
pedals 287-301
adjustment 292-3
bearing overhaul 296-7, 296-7,
300-1, 300-1
checking 112
cleaning 292
clipless 287, 288, 289-90
adjusting 291
maintenance 290-1, 294-5, 294-5
disassembling 292
greasing 292
Look, bearing overhaul 300-1, 300-1
maintenance 298-9, 298-9
removing 108, 291-2
repair 298-9, 298-9
servicing 291
Shimano SPIN, bearing overhaul
296-7, 296-7
troubleshooting 293
types 287-90, 287, 290
pegboard 17
Phillips screwdriver 16
pin spanner, adjustable 16
pinch-flats 60
platform pedals 287, 289
pliers 16, 17
preload adjustments 44-5
Presta valve 60
preventive maintenance 18-22
Q
quill pedals 287, 289
R
racing bikes 52
frame geometry 32
saddles 277
tyres 49
rattrap pedals 287, 289
rims 49
maintenance 80-1, 80-1
repairing 80-1, 80-1
width 51, 52
road bikes:
derailleurs 185, 185
gearing 305-6
handlebars 259, 260-1, 260
removing and installing 269, 269
shift levers 155, 157-9, 160
stems, removing and installing 268-9,
268-9
road racing bikes:
frame geometry 32-3
wheels 54
road sport touring bike, frame geometry
33
S
saddle covers 277
saddles 275-85
adjustment 282-5, 282-5
anatomic 275
construction 275-7, 276
cutaway 275, 277
height 278-9
installing 281-2, 281-2
position 279
selecting 277-8
suspension 43
tilt 278
troubleshooting 280
types 277
women's 275, 277
Schrader valve 60
scouring pads 20
screwdrivers 16, 17
screws:
centring 228
stuck 36
seat angle 27, 31
seatposts 278
suspension 279-80, 279
troubleshooting 280
seatstays 27
shift levers 155-71
bar-end 155, 157-8, 159-60, 164-5,
164-5
braze-on 161-3, 161-3
down-tube 155, 157, 158-9
installing 159-60, 161-71, 161-71
locations 155-7
320 ILLUSTRATED BICYCLE MAINTENANCE
performance 157
removing 157-8
servicing 158-9
technology 156
three-speed type 171, 171
thumb shifter 170, 170
troubleshooting 160
twist 155, 157, 159, 168-9,
168-9
types 155
shimmy 36
shoes 287, 289
shorts 278
soft tail 43, 43
solvents 20
spanners, adjustable 16, 17
speed wobble 36
spindle removal tool 296, 296
spindles 103, 105, 112
spoke key 16
spoke protectors 191
spokes 49
broken 63, 64
damage to 55, 63
maintenance 82, 82
replacement 82-3, 82-3
tension 49, 54-5, 62-3
springs 39, 44-5
rate progressions 44
sprockets see cogs
standover clearance 33
stands 17, 17
steel 30-1, 36
stems, handlebar 257-73
adjusting 263-4, 265-7, 265-7
compatibility with bar 259-60
frozen 204
installing 261-2, 269, 269
quill-style 257
removing 268-9, 268-9
size 257
suspension 41
threadless 257-9
troubleshooting 264
types 257-80
suspension 17, 39-47, 40-3, 46-7
adjustments 44-5, 46-7, 46-7
front 39-41, 40, 41, 42
maintenance 45
rear 41-3, 43
troubleshooting 45
suspension seatposts 279-80, 279
suspension stems 41
tandems 217, 222
third hand tool 16, 224
titanium 31, 36
toe-in 228
toe-straps 290
installing 299, 299
toeclips 289, 290
tool kit 21
tools 15, 16, 17-18, 19
multi 20
pro mechanic's 18
storage 17
touring bikes:
brakes 222
frame geometry 32, 33
handlebars 261
track bikes 54, 131
trail 32
trials bike 34
triathlon bikes 54
truing 84-5, 84-5
tubes:
frame see frames
inner:
installing 58
repairing 57-8
size 57
Two-niners 34
tyre levers 16, 58
tyres:
see also tubes, inner
casings 51-2
clincher:
remounting 70-1, 70-1
removing 59, 68-9, 68-9
repairing 68-70, 68-70
emergency repairs 63-4
inflation pressures 51, 55
maintenance schedule 18
mounting 57-9
removing 57, 59
rim compatibility 52
selecting 51-2
sizes 51-2
structure 49-51, 50
tubeless (UST) 59-60
mounting 60, 62, 74-5, 74-5
removing 59, 72, 72
repairing 59-60, 70-4, 72-4
tubular 54
gluing 61
patching 61-2
remounting 78-9, 78-9
removing 76, 76
repairing 76-8, 76-8
types 49, 51
valves 57, 58-9, 60
V
velocipedes 131
w
water bottle mounts 36
waxing 36
WD-40 20
wheel tracking 37
wheels 49-85
see also hubs; rims; spokes; tubes; tyres
cleaning 18
compatibility with bike 52-4
custom-built 49
diameter 51, 52
emergency repairs 63-4
maintenance 54-6, 62-3
mounting 56, 57, 67, 67
removing 56-7, 66-7, 66-7
repairing 62-3, 80-1, 80-1
selecting 51-2
sizes 30, 51
special-use 54
straightening, emergency 64
structure 49, 50
troubleshooting 64-5
truing 84-5, 84-5
wheel systems 54
women's saddles 275, 277
work space 17-18
workbench 17
workstand see stands
wrenches 16
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