2010
Read this manual carefully before operating this vehicle.
Il convient de lire attentivement ce manuel avant la première utilisation du véhicule.
Bitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen.
Leggere attentamente questo manuale prima di utilizzare questo veicolo.
YZ250F(Z)
2010
PRINTED ON RECYCLED PAPER
YAMAHA MOTOR CO., LTD.
2500 SHINGAI IWATA SHIZUOKA JAPAN
PRINTED IN JAPAN
2009.05-2.0×1 CR
(E,F,G,H)
OWNER’S SERVICE MANUAL
MANUEL D’ATELIER DU
PROPRIETAIRE
FAHRER- UND
WARTUNGSHANDBUCH
MANUALE DI SERVIZIO DEL
PROPRIETARIO
YZ250F(Z)
17D-28199-30
Read this manual carefully before operating this vehicle. This manual should stay with this vehicle if it is sold.
Il convient de lire attentivement ce manuel avant la première utilisation du véhicule. Le manuel doit être remis
avec le véhicule en cas de vente de ce dernier.
Bitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen. Diese
Bedienungsanleitung muss, wenn das Fahrzeug verkauft wird, beim Fahrzeug verbleiben.
Leggere attentamente questo manuale prima di utilizzare il veicolo. Questo manuale dovrebbe accompagnare il veicolo se viene venduto.
2010
Read this manual carefully before operating this vehicle.
OWNER’S SERVICE MANUAL
YZ250F(Z)
17D-28199-30-E0
YZ250F(Z)
OWNER'S SERVICE MANUAL
©2009 by Yamaha Motor Co., Ltd.
1st Edition, May 2009
All rights reserved.Any reprinting or
unauthorized use without the written
permission of Yamaha Motor Co., Ltd.
is expressly prohibited.
Printed in Japan
FOREWORD
INTRODUCTION
Congratulations on your purchase of
a Yamaha YZ series. This model is
the culmination of Yamaha's vast experience in the production of pacesetting racing machines. It represents
the highest grade of craftsmanship
and reliability that have made Yamaha a leader.
This manual explains operation, inspection, basic maintenance and tuning of your machine. If you have any
questions about this manual or your
machine, please contact your Yamaha dealer.
Yamaha continually seeks advancements in product design and quality.
Therefore, while this manual contains
the most current product information
available at the time of printing, there
may be minor discrepancies between
your machine and this manual. If you
have any questions concerning this
manual, please consult your Yamaha
dealer.
PLEASE READ THIS MANUAL
CAREFULLY AND COMPLETELY
BEFORE OPERATING THIS MACHINE. DO NOT ATTEMPT TO OPERATE THIS MACHINE UNTIL YOU
HAVE ATTAINED A SATISFACTORY KNOWLEDGE OF ITS CONTROLS AND OPERATING
FEATURES AND UNTIL YOU HAVE
BEEN TRAINED IN SAFE AND
PROPER RIDING TECHNIQUES.
REGULAR INSPECTIONS AND
CAREFUL MAINTENANCE,
ALONG WITH GOOD RIDING
SKILLS, WILL ENSURE THAT YOU
SAFETY ENJOY THE CAPABILITIES AND THE RELIABILITY OF
THIS MACHINE.
IMPORTANT MANUAL
INFORMATION
Particularly important information is
distinguished in this manual by the
following notations.
This is the safety alert symbol. It is
used to alert you to potential personal injury hazards. Obey all safety messages that follow this
symbol to avoid possible injury or
death.
A WARNING indicates a hazardous
situation which, if not avoided,
could result in death or serious injury.
A NOTICE indicates special precautions that must be taken to
avoid damage to the vehicle or other property.
A TIP provides key information to
make procedures easier or clearer.
SAFETY INFORMATION
THIS MACHINE IS DESIGNED
STRICTLY FOR COMPETITION
USE, ONLY ON A CLOSED
COURSE. It is illegal for this machine
to be operated on any public street,
road, or highway. Off-road use on
public lands may also be illegal.
Please check local regulations before
riding.
• THIS MACHINE IS TO BE OPERATED BY AN EXPERIENCED RIDER ONLY.
Do not attempt to operate this machine at maximum power until you
are totally familiar with its characteristics.
• THIS MACHINE IS DESIGNED TO
BE RIDDEN BY THE OPERATOR
ONLY.
Do not carry passengers on this
machine.
• ALWAYS WEAR PROTECTIVE
APPAREL.
When operating this machine, always wear an approved helmet with
goggles or a face shield. Also wear
heavy boots, gloves, and protective
clothing. Always wear proper fitting
clothing that will not be caught in
any of the moving parts or controls
of the machine.
• ALWAYS MAINTAIN YOUR MACHINE IN PROPER WORKING
ORDER.
For safety and reliability, the machine must be properly maintained.
Always perform the pre-operation
checks indicated in this manual.
Correcting a mechanical problem
before you ride may prevent an accident.
• GASOLINE IS HIGHLY FLAMMABLE.
Always turn off the engine while refueling. Take care to not spill any
gasoline on the engine or exhaust
system. Never refuel in the vicinity
of an open flame, or while smoking.
• GASOLINE CAN CAUSE INJURY.
If you should swallow some gasoline, inhale excess gasoline vapors,
or allow any gasoline to get into
your eyes, contact a doctor immediately. If any gasoline spills onto
your skin or clothing, immediately
wash skin areas with soap and water, and change your clothes.
• ONLY OPERATE THE MACHINE
IN AN AREA WITH ADEQUATE
VENTILATION.
Never start the engine or let it run
for any length of time in an enclosed
area. Exhaust fumes are poisonous. These fumes contain carbon
monoxide, which by itself is odorless and colorless. Carbon monoxide is a dangerous gas which can
cause unconsciousness or can be
lethal.
• PARK THE MACHINE CAREFULLY; TURN OFF THE ENGINE.
Always turn off the engine if you are
going to leave the machine. Do not
park the machine on a slope or soft
ground as it may fall over.
• THE ENGINE, EXHAUST PIPE,
MUFFLER, AND OIL TANK WILL
BE VERY HOT AFTER THE ENGINE HAS BEEN RUN.
Be careful not to touch them or to
allow any clothing item to contact
them during inspection or repair.
• PROPERLY SECURE THE MACHINE BEFORE TRANSPORTING
IT.
When transporting the machine in
another vehicle, always be sure it is
properly secured and in an upright
position and that the fuel cock is in
the "OFF" position. Otherwise, fuel
may leak out of the carburetor or
fuel tank.
F.I.M. MACHINE WEIGHTS
Weights of machines without fuel
The minimum weights for motocross
machines are:
for the class 125 cc:
minimum 88 kg (194 lb)
for the class 250 cc:
minimum 98 kg (216 lb)
for the class 500 cc:
minimum 102 kg (225 lb)
In modifying your machine (e.g., for
weight reduction), take note of the
above limits of weight.
HOW TO USE THIS MANUAL
FINDING THE REQUIRED PAGE
1. This manual consists of seven
chapters; "General Information",
"Specifications", "Regular inspection and adjustments", "Engine",
"Chassis", "Electrical" and "Tuning"
2. The table of contents is at the beginning of the manual. Look over
the general layout of the book before finding then required chapter
and item.
Bend the book at its edge, as
shown, to find the required fore
edge symbol mark and go to a
page for required item and description.
MANUAL FORMAT
All of the procedures in this manual
are organized in a sequential, stepby-step format. The information has
been complied to provide the mechanic with an easy to read, handy
reference that contains comprehensive explanations of all disassembly,
repair, assembly, and inspection operations.
In this revised format, the condition of
a faulty component will precede an
arrow symbol and the course of action required will follow the symbol,
e.g.,
• Bearings
Pitting/damage → Replace.
HOW TO READ DESCRIPTIONS
To help identify parts and clarify procedure steps, there are exploded diagrams at the start of each removal
and disassembly section.
1. An easy-to-see exploded diagram
"1" is provided for removal and
disassembly jobs.
3
2. Numbers "2" are given in the order of the jobs in the exploded diagram. A number that is enclosed
by a circle indicates a disassembly step.
3. An explanation of jobs and notes
is presented in an easy-to-read
way by the use of symbol marks
"3". The meanings of the symbol
marks are given on the next page.
4. A job instruction chart "4" accompanies the exploded diagram,
providing the order of jobs, names
of parts, notes in jobs, etc.
5. For jobs requiring more information, the step-by-step format supplements "5" are given in addition
to the exploded diagram and job
instruction chart.
5
1
2
4
ILLUSTRATED SYMBOLS (Refer to
the illustration)
Illustrated symbols "1" to "7" are used
to identify the specifications appearing in the text.
1. With engine mounted
2. Filling fluid
3. Lubricant
4. Special tool
5. Tightening
6. Specified value, Service limit
7. Resistance (Ω), Voltage (V),
Electric current (A)
Illustrated symbols "8" to "13" in the
exploded diagrams indicate grade of
lubricant and location of lubrication
point.
8. Apply engine oil
9. Apply molybdenum disulfide oil
10. Apply brake fluid
11. Apply lightweight lithium-soap
base grease
12. Apply molybdenum disulfide
grease
13. Apply silicone grease
Illustrated symbols "14" to "15" in the
exploded diagrams indicate where to
apply a locking agent and where to install new parts.
14. Apply locking agent (LOCTITE®)
15. Use new one
TABLE OF CONTENTS
GENERAL INFORMATION
1
SPECIFICATIONS
2
REGULAR INSPECTION AND
ADJUSTMENTS
3
ENGINE
4
CHASSIS
5
ELECTRICAL
6
TUNING
7
CONTENTS
CHAPTER 1
GENERAL
INFORMATION
LOCATION OF
IMPORTANT LABELS ..... 1-1
DESCRIPTION ................. 1-5
CONSUMER
INFORMATION................. 1-6
INCLUDED PARTS .......... 1-6
IMPORTANT
INFORMATION................. 1-6
CHECKING OF
CONNECTION.................. 1-7
SPECIAL TOOLS ............. 1-8
CONTROL
FUNCTIONS ................... 1-12
STARTING AND
BREAK-IN ...................... 1-13
TORQUE-CHECK
POINTS........................... 1-15
CLEANING AND
STORAGE ...................... 1-16
CHAPTER 2
SPECIFICATIONS
GENERAL
SPECIFICATIONS............ 2-1
MAINTENANCE
SPECIFICATIONS............ 2-3
TIGHTENING
TORQUES ...................... 2-10
LUBRICATION
DIAGRAMS .................... 2-16
CABLE ROUTING
DIAGRAM....................... 2-18
CHAPTER 3
REGULAR
INSPECTION AND
ADJUSTMENTS
MAINTENANCE
INTERVALS...................... 3-1
PRE-OPERATION
INSPECTION AND
MAINTENANCE................ 3-5
ENGINE ............................ 3-6
CHASSIS ........................ 3-14
ELECTRICAL ................. 3-24
CHAPTER 4
ENGINE
SEAT, FUEL TANK AND
SIDE COVERS.................. 4-1
EXHAUST PIPE AND
SILENCER ........................ 4-3
RADIATOR ....................... 4-5
CARBURETOR................. 4-7
CAMSHAFTS.................. 4-14
CYLINDER HEAD........... 4-19
VALVES AND VALVE
SPRINGS ........................ 4-21
CYLINDER AND
PISTON........................... 4-25
CLUTCH ......................... 4-29
OIL FILTER ELEMENT
AND WATER PUMP....... 4-33
BALANCER .................... 4-38
OIL PUMP....................... 4-40
KICK SHAFT AND
SHIFT SHAFT................. 4-44
CDI MAGNETO............... 4-49
ENGINE REMOVAL ....... 4-51
CRANKCASE AND
CRANKSHAFT ............... 4-55
TRANSMISSION,
SHIFT CAM AND
SHIFT FORK................... 4-61
CHAPTER 5
CHASSIS
FRONT WHEEL AND
REAR WHEEL ..................5-1
FRONT BRAKE AND
REAR BRAKE ..................5-6
FRONT FORK.................5-16
HANDLEBAR..................5-24
STEERING ......................5-28
SWINGARM ....................5-31
REAR SHOCK
ABSORBER....................5-36
CHAPTER 6
ELECTRICAL
ELECTRICAL
COMPONENTS AND
WIRING DIAGRAM ...........6-2
IGNITION SYSTEM...........6-3
THROTTLE POSITION
SENSOR SYSTEM ...........6-6
CHAPTER 7
TUNING
ENGINE.............................7-1
CHASSIS ..........................7-6
LOCATION OF IMPORTANT LABELS
GENERAL INFORMATION
LOCATION OF IMPORTANT LABELS
Please read the following important labels carefully before operating this vehicle.
1
CANADA
1-1
LOCATION OF IMPORTANT LABELS
EUROPE
1-2
LOCATION OF IMPORTANT LABELS
AUS, NZ, ZA
1-3
LOCATION OF IMPORTANT LABELS
Familiarize yourself with the following pictograms and read the explanatory text.
Read Owner’s service manual.
This unit contains high-pressure nitrogen gas. Mishandling can cause explosion. Do not incinerate,
puncture or open.
Turn off the main switch after riding to avoid draining the battery.
Use unleaded gasoline only.
Measure tire pressure when tires are cold.
Adjust tire pressure.
Improper tire pressure can cause loss of control.
Loss of control can result in severe injury or death.
1-4
DESCRIPTION
DESCRIPTION
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
Clutch lever
Hot starter lever
Front brake lever
Throttle grip
Radiator cap
Fuel tank cap
Engine stop switch
Kickstarter crank
Fuel tank
Radiator
Coolant drain bolt
Rear brake pedal
Valve joint
14.
15.
16.
17.
18.
19.
20.
Fuel cock
Cold starter knob
Air filter
Drive chain
Shift pedal
Oil level check window
Front fork
• The machine you have purchased may differ slightly from those shown in the following.
• Designs and specifications are subject to change without notice.
1-5
CONSUMER INFORMATION
CONSUMER INFORMATION
There are two significant reasons for
knowing the serial number of your
machine:
1. When ordering parts, you can
give the number to your Yamaha
dealer for positive identification of
the model you own.
2. If your machine is stolen, the authorities will need the number to
search for and identify your machine.
VEHICLE IDENTIFICATION
NUMBER
The vehicle identification number "1"
is stamped on the right of the steering
head pipe.
ENGINE SERIAL NUMBER
The engine serial number "1" is
stamped into the elevated part of the
right-side of the engine.
MODEL LABEL
The model label "1" is affixed to the
frame under the rider's seat. This information will be needed to order
spare parts.
HANDLEBAR PROTECTOR
Install the handlebar protector "1" so
that the mark "a" face forward.
VALVE JOINT
This valve joint "1" prevents fuel from
flowing out and is installed to the fuel
tank breather hose.
In this installation, make sure the
arrow faces the fuel tank and also
downward.
SPARK PLUG WRENCH
This spark plug wrench "1" is used to
remove and install the spark plug.
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL
AND DISASSEMBLY
1. Remove all dirt, mud, dust, and
foreign material before removal
and disassembly.
• When washing the machine with
high pressured water, cover the
parts follows.
Silencer exhaust port
Side cover air intake port
Water pump housing hole at the
bottom
Drain hole on the cylinder head
(right side)
NIPPLE WRENCH
This nipple wrench "1" is used to
tighten the spoke.
2. Use proper tools and cleaning
equipment. Refer to "SPECIAL
TOOLS" section.
INCLUDED PARTS
JET NEEDLE PULL-UP TOOL
The jet needle pull-up tool "1" is used
to pull the jet needle out of the carburetor.
DETACHABLE SIDESTAND
This sidestand "1" is used to support
only the machine when standing or
transporting it.
3. When disassembling the machine, keep mated parts together.
They include gears, cylinders,
pistons, and other mated parts
that have been "mated" through
normal wear. Mated parts must
be reused as an assembly or replaced.
• Never apply additional force to
the sidestand.
• Remove this sidestand before
starting out.
1-6
CHECKING OF CONNECTION
4. During the machine disassembly,
clean all parts and place them in
trays in the order of disassembly.
This will speed up assembly time
and help assure that all parts are
correctly reinstalled.
5. Keep away from fire.
ALL REPLACEMENT PARTS
1. We recommend to use Yamaha
genuine parts for all replacements. Use oil and/or grease recommended by Yamaha for
assembly and adjustment.
GASKETS, OIL SEALS AND ORINGS
1. All gaskets, oil seals, and O-rings
should be replaced when an engine is overhauled. All gasket surfaces, oil seal lips, and O-rings
must be cleaned.
2. Properly oil all mating parts and
bearings during reassembly. Apply grease to the oil seal lips.
LOCK WASHERS/PLATES AND
COTTER PINS
1. All lock washers/plates "1" and
cotter pins must be replaced
when they are removed. Lock
tab(s) should be bent along the
bolt or nut flat(s) after the bolt or
nut has been properly tightened.
BEARINGS AND OIL SEALS
1. Install the bearing(s) "1" and oil
seal(s) "2" with their manufacturer's marks or numbers facing outward. (In other words, the
stamped letters must be on the
side exposed to view.) When installing oil seal(s), apply a light
coating of lightweight lithium base
grease to the seal lip(s). Oil the
bearings liberally when installing.
Do not use compressed air to spin
the bearings dry. This causes damage to the bearing surfaces.
2. Dry each terminal with an air
blower.
3. Connect and disconnect the connector two or three times.
4. Pull the lead to check that it will
not come off.
5. If the terminal comes off, bend up
the pin "1" and reinsert the terminal into the connector.
6. Connect:
• Connector
The two connectors "click" together.
7. Check for continuity with a tester.
CIRCLIPS
1. All circlips should be inspected
carefully before reassembly. Always replace piston pin clips after
one use. Replace distorted circlips. When installing a circlip "1",
make sure that the sharp-edged
corner "2" is positioned opposite
to the thrust "3" it receives. See
the sectional view.
CHECKING OF
CONNECTION
Dealing with stains, rust, moisture,
etc. on the connector.
1. Disconnect:
• Connector
1-7
• If there in no continuity, clean the
terminals.
• Be sure to perform the steps 1 to 7
listed above when checking the
wire harness.
• For a field remedy, use a contact revitalizer available on the market.
• Use the tester on the connector as
shown.
SPECIAL TOOLS
SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the correct special tool will
help prevent damage caused by the use of improper tools or improvised techniques. The shape and part number used for
the special tool differ by country, so two types are provided. Refer to the list provided to avoid errors when placing an order.
• For U.S.A. and Canada, use part number starting with "YM-", "YU-" or "ACC-".
• For others, use part number starting with "90890-".
Tool name/Part number
How to use
Crankcase separating tool
YU-1135-A, 90890-01135
These tool is used to remove the
crankshaft from either case.
Flywheel puller
YM-1189, 90890-01189
This tool is used to remove the flywheel magneto.
Rotor holding tool
YU-1235, 90890-01235
This tool is used when loosening or
tightening the flywheel magneto securing nut.
Dial gauge and stand
YU-3097, 90890-01252
Stand
YU-1256
These tools are used to check each
part for runout or bent.
Crankshaft installing tool
Crankshaft installing pot
YU-90050, 90890-01274
Crankshaft installing bolt
YU-90050, 90890-01275
Spacer (crankshaft installer)
YU-91044, 90890-04081
Adapter (M12)
YU-90063, 90890-01278
These tools are used to install the
crankshaft.
Piston pin puller set
YU-1304, 90890-01304
This tool is used to remove the piston pin.
1-8
Illustration
SPECIAL TOOLS
Tool name/Part number
How to use
Radiator cap tester
YU-24460-01, 90890-01325
Radiator cap tester adapter
YU-33984, 90890-01352
These tools are used for checking
the cooling system.
Steering nut wrench
YU-33975, 90890-01403
This tool is used when tighten the
steering ring nut to specification.
Cap bolt wrench
YM-01500, 90890-01500
This tool is used to loosen or tighten
the base valve.
Cap bolt ring wrench
YM-01501, 90890-01501
This tool is used to loosen or tighten
the damper assembly.
Fork seal driver
YM-A0948, 90890-01502
This tool is used when install the fork
oil seal.
Spoke nipple wrench
YM-01521, 90890-01521
This tool is used to tighten the
spoke.
Pocket tester
YU-3112-C, 90890-03112
Use this tool to inspect the coil resistance, output voltage and amperage.
1-9
Illustration
SPECIAL TOOLS
Tool name/Part number
How to use
Timing light
YM-33277-A, 90890-03141
This tool is necessary for checking
ignition timing.
Valve spring compressor
YM-4019, 90890-04019
This tool is needed to remove and
install the valve assemblies.
Clutch holding tool
YM-91042, 90890-04086
This tool is used to hold the clutch
when removing or installing the
clutch boss securing nut.
Valve guide remover
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
YM-4111, 90890-04111
YM-4116, 90890-04116
This tool is needed to remove and
install the valve guide.
Valve guide installer
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
YM-4112, 90890-04112
YM-4117, 90890-04117
This tool is needed to install the
valve guide.
Valve guide reamer
Intake 4.0 mm (0.16 in)
Exhaust 4.5 mm (0.18 in)
YM-4113, 90890-04113
YM-4118, 90890-04118
This tool is needed to rebore the
new valve guide.
1-10
Illustration
SPECIAL TOOLS
Tool name/Part number
How to use
Dynamic spark tester
YM-34487
Ignition checker
90890-06754
This instrument is necessary for
checking the ignition system components.
Digital tachometer
YU-39951-B, 90890-06760
This tool is needed for observing engine rpm.
YAMAHA Bond No. 1215 (ThreeBond® No. 1215)
90890-85505
This sealant (Bond) is used for
crankcase mating surface, etc.
1-11
Illustration
CONTROL FUNCTIONS
CONTROL FUNCTIONS
ENGINE STOP SWITCH
The engine stop switch "1" is located
on the left handlebar. Continue pushing the engine stop switch till the engine comes to a stop.
THROTTLE GRIP
The throttle grip "1" is located on the
right handlebar; it accelerates or decelerates the engine. For acceleration, turn the grip toward you; for
deceleration, turn it away from you.
CLUTCH LEVER
The clutch lever "1" is located on the
left handlebar; it disengages or engages the clutch. Pull the clutch lever
to the handlebar to disengage the
clutch, and release the lever to engage the clutch. The lever should be
pulled rapidly and released slowly for
smooth starts.
SHIFT PEDAL
The gear ratios of the constant-mesh
5 speed transmission are ideally
spaced. The gears can be shifted by
using the shift pedal "1" on the left
side of the engine.
FRONT BRAKE LEVER
The front brake lever "1" is located on
the right handlebar. Pull it toward the
handlebar to activate the front brake.
FUEL COCK
The fuel cock supplies fuel from the
tank to carburetor and also filters the
fuel. The fuel cock has the two positions:
OFF:
With the lever in this position, fuel will
not flow. Always return the lever to
this position when the engine is not
running.
ON:
With the lever in this position, fuel
flows to the carburetor. Normal riding
is done with the lever in this position.
COLD STARTER KNOB
When cold, the engine requires a
richer air-fuel mixture for starting. A
separate starter circuit, which is controlled by the cold starter knob "1",
supplies this mixture. Pull the cold
starter knob out to open the circuit for
starting. When the engine has
warmed up, push it in to close the circuit.
REAR BRAKE PEDAL
The rear brake pedal "1" is located on
the right side of the machine. Press
down on the brake pedal to activate
the rear brake.
HOT STARTER LEVER
The hot starter lever "1" is used when
starting a warm engine. Use the hot
starter lever when starting the engine
again immediately after it was
stopped (the engine is still warm).
Pulling the hot starter lever injects
secondary air to thin the air-fuel mixture temporarily, allowing the engine
to be started more easily.
KICKSTARTER CRANK
Rotate the kickstarter crank "1" away
from the engine. Push the starter
down lightly with your foot until the
gears engage, then kick smoothly
and forcefully to start the engine. This
model has a primary kickstarter crank
so the engine can be started in any
gear if the clutch is disengaged. In
normal practices, however, shift to
neutral before starting.
1-12
STARTING AND BREAK-IN
STARTING AND BREAK-IN
FUEL
Always use the recommended fuel as
stated below. Also, be sure to use
new gasoline the day of a race.
Recommended fuel:
Premium unleaded
gasoline only with a research octane number
of 95 or higher.
Use only unleaded gasoline. The
use of leaded gasoline will cause
severe damage to the engine internal parts such as valves, piston
rings, and exhaust system, etc.
AIR FILTER MAINTENANCE
According to "CLEANING THE AIR
FILTER ELEMENT" section in the
CHAPTER 3, apply the foam-air-filter
oil or its equivalent to the element.
(Excess oil in the element may adversely affect engine starting.)
STARTING A COLD ENGINE
1. Inspect the coolant level.
2. Turn the fuel cock to "ON".
3. Shift the transmission into neutral.
4. Fully open the cold starter knob
"1".
5. Kick the kickstarter crank.
HANDLING NOTE
Never start or run the engine in a
closed area. The exhaust fumes
are poisonous; they can cause
loss of consciousness and death
in a very short time. Always operate the machine in a well-ventilated
area.
• The carburetor on this machine
has a built-in accelerator pump.
Therefore, when starting the engine, do not operate the throttle
or the spark plug will foul.
• Unlike a two-stroke engine, this
engine cannot be kick started
when the throttle is open because the kickstarter may kick
back. Also, if the throttle is open
the air/fuel mixture may be too
lean for the engine to start.
• Before starting the machine, perform the checks in the pre-operation check list.
Thrott
Cold Hot
le
start- startgrip
er er leoperknob ver
ation*
Air temperature = Open
less than 3 or 4
times
5 °C (41
°F)
If knocking or pinging occurs, use a
different brand of gasoline or higher
octane grade.
• For refueling, be sure to stop the
engine and use enough care not
to spill any fuel. Also be sure to
avoid refueling close to a fire.
• Refuel after the engine, exhaust
pipe, etc. have cooled off.
Restarting an engine after a fall
Pull the hot starter lever and start the
engine. As soon as the engine starts,
release the hot starter lever to close
the air passage.
The engine fails to start
Pull the hot starter lever all the way
out and while holding the lever, kick
the kickstarter crank 10 to 20 times to
clear the engine. Then, restart the engine. Refer to "Restarting an engine
after a fall".
Do not open the throttle while kicking the kickstarter crank. Otherwise, the kickstarter crank may
kick back.
6. Return the cold starter knob to its
original position and run the engine at 3,000–5,000 r/min for 1 or
2 minutes.
Since this model is equipped with an
accelerator pump, if the engine is
raced (the throttle opened and
closed), the air/fuel mixture will be too
rich and the engine may stall. Also
unlike a two-stroke engine, this model
can idle.
Do not warm up the engine for extended periods of time.
STARTING A WARM ENGINE
Do not operate the cold starter knob
and throttle. Pull the hot starter lever
"1" and start the engine by kicking
the kickstarter crank forcefully with a
firm stroke. As soon as the engine
starts, release the hot starter lever to
close the air passage.
ON
Air temperature =
more than None ON
5 °C (41
Star °F)
ting Air tema
perature
cold (normal
en- temperagine ture) = be- None ON/
OFF
tween 5
°C (41 °F)
and 25 °C
(77 °F)
Air temperature =
more than None OFF
25 °C (77
°F)
OFF
OFF
OFF
OFF
Starting an engine after a long
period of time
None
ON
OFF
Restarting a
warm engine
None OFF
ON
Restarting an
engine after a
fall
None OFF
ON
* Operate the throttle grip before kick
starting.
Observe the following break-in
procedures during initial operation
to ensure optimum performance
and avoid engine damage.
1-13
STARTING AND BREAK-IN
BREAK-IN PROCEDURES
1. Before starting the engine, fill the
fuel tank with the fuel.
2. Perform the pre-operation checks
on the machine.
3. Start and warm up the engine.
Check the idle speed, and check
the operation of the controls and
the engine stop switch. Then, restart the engine and check its operation within no more than 5
minutes after it is restarted.
4. Operate the machine in the lower
gears at moderate throttle openings for five to eight minutes.
5. Check how the engine runs when
the machine is ridden with the
throttle 1/4 to 1/2 open (low to medium speed) for about one hour.
6. Restart the engine and check the
operation of the machine throughout its entire operating range. Restart the machine and operate it
for about 10 to 15 more minutes.
The machine will now be ready to
race.
• After the break-in or before each
race, you must check the entire
machine for loose fittings and
fasteners as per "TORQUECHECK POINTS". Tighten all
such fasteners as required.
• When any of the following parts
have been replaced, they must
be broken in.
CYLINDER AND CRANKSHAFT:
About one hour of break-in operation is necessary.
PISTON, RING, VALVES, CAMSHAFTS AND GEARS:
These parts require about 30
minutes of break-in operation at
half-throttle or less. Observe the
condition of the engine carefully
during operation.
1-14
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Frame construction
Frame to rear frame
Combined seat and fuel tank
Fuel tank to frame
Exhaust system
Silencer to rear frame
Engine mounting
Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering
Steering stem to handlebar
Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension
Front
Steering stem to front fork
Rear
For link type
Front fork to upper bracket
Front fork to lower bracket
Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Wheel
Installation of rear shock absorber
Rear shock absorber to frame
Installation of swingarm
Tightening of pivot shaft
Installation of wheel
Front
Tightening of wheel axle
Rear
Tightening of wheel axle
Tightening of axle holder
Wheel to rear wheel sprocket
Brake
Front
Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Tightening of brake hose holder
Rear
Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Fuel system
Fuel tank to fuel cock
Lubrication system
Tightening of oil hose clamp
Concerning the tightening torque, refer to "TIGHTENING TORQUES" section in the CHAPTER 2.
1-15
CLEANING AND STORAGE
CLEANING AND STORAGE
CLEANING
Frequent cleaning of your machine
will enhance its appearance, maintain
good overall performance, and extend the life of many components.
1. Before washing the machine,
block off the end of the exhaust
pipe to prevent water from entering. A plastic bag secured with a
rubber band may be used for this
purpose.
2. If the engine is excessively
greasy, apply some degreaser to
it with a paint brush. Do not apply
degreaser to the chain, sprockets,
or wheel axles.
3. Rinse the dirt and degreaser off
with a garden hose; use only
enough pressure to do the job.
Excessive hose pressure may
cause water seepage and contamination of wheel bearings, front
forks, brakes and transmission
seals. Many expensive repair bills
have resulted from improper high
pressure detergent applications
such as those available in coin-operated car washers.
4. After the majority of the dirt has
been hosed off, wash all surfaces
with warm water and a mild detergent. Use an old toothbrush to
clean hard-to-reach places.
5. Rinse the machine off immediately with clean water, and dry all
surfaces with a soft towel or cloth.
6. Immediately after washing, remove excess water from the
chain with a paper towel and lubricate the chain to prevent rust.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover
pliable and glossy.
8. Automotive wax may be applied
to all painted or chromed surfaces. Avoid combination cleanerwaxes, as they may contain abrasives.
9. After completing the above, start
the engine and allow it to idle for
several minutes.
STORAGE
If your machine is to be stored for 60
days or more, some preventive measures must be taken to avoid deterioration. After cleaning the machine
thoroughly, prepare it for storage as
follows:
1. Drain the fuel tank, fuel lines, and
the carburetor float bowl.
2. Remove the spark plug, pour a tablespoon of SAE 10W-40 motor
oil in the spark plug hole, and reinstall the plug. With the engine
stop switch pushed in, kick the engine over several times to coat the
cylinder walls with oil.
3. Remove the drive chain, clean it
thoroughly with solvent, and lubricate it. Reinstall the chain or store
it in a plastic bag tied to the frame.
4. Lubricate all control cables.
5. Block the frame up to raise the
wheels off the ground.
6. Tie a plastic bag over the exhaust
pipe outlet to prevent moisture
from entering.
7. If the machine is to be stored in a
humid or salt-air environment,
coat all exposed metal surfaces
with a film of light oil. Do not apply
oil to rubber parts or the seat cover.
Make any necessary repairs before
the machine is stored.
1-16
GENERAL SPECIFICATIONS
SPECIFICATIONS
GENERAL SPECIFICATIONS
Model name:
YZ250FZ (USA, CDN, AUS, NZ)
YZ250F (EUROPE, ZA)
Model code number:
17D5 (USA,CDN)
17D6 (EUROPE)
17D8 (AUS, NZ, ZA)
Dimensions:
USA, CDN
EUROPE
2,168 mm (85.35
in)
AUS, NZ, ZA
Overall length
2,159 mm (85.00
in)
Overall width
825 mm (32.48 in) ←
←
Overall height
1,303 mm (51.30
in)
←
Seat height
988 mm (38.90 in) 991 mm (39.02 in) 990 mm (38.98 in)
Wheelbase
1,466 mm (57.72
in)
Minimum ground clearance
375 mm (14.76 in) 377 mm (14.84 in) 376 mm (14.80 in)
1,304 mm (51.34
in)
1,473 mm (57.99
in)
2,166 mm (85.28
in)
←
Weight:
With oil and fuel
102.0 kg (224.9 lb)
Engine:
Engine type
Liquid cooled 4-stroke, DOHC
Cylinder arrangement
Single cylinder, forward inclined
Displacement
250 cm3 (8.80 Imp oz, 8.45 US oz)
Bore × stroke
77.0 × 53.6 mm (3.03 × 2.11 in)
Compression ratio
13.5 : 1
Starting system
Kickstarter
Lubrication system:
Dry sump
Oil type or grade:
Engine oil
Recommended brand: YAMALUBE
SAE10W-30, SAE10W-40, SAE10W-50
SAE15W-40, SAE20W-40 or SAE20W-50
API service SG type or higher,
JASO standard MA
Oil capacity:
Engine oil
Periodic oil change
0.95 L (0.84 Imp qt, 1.00 US qt)
With oil filter replacement
1.05 L (0.92 Imp qt, 1.11 US qt)
Total amount
1.20 L (1.06 Imp qt, 1.27 US qt)
Coolant capacity (including all routes):
1.00 L (0.88 Imp qt, 1.06 US qt)
Air filter:
Wet type element
Fuel:
Type
Premium unleaded gasoline only with a research octane
number of 95 or higher.
Tank capacity
6.4 L (1.4 Imp gal, 1.69 US gal)
2-1
2
GENERAL SPECIFICATIONS
Carburetor:
Type
FCR-MX37
Manufacturer
KEIHIN
Spark plug:
Type/manufacturer
CR8E/NGK (resistance type)
Gap
0.7–0.8 mm (0.028–0.031 in)
Clutch type:
Wet, multiple-disc
Transmission:
USA, CDN
EUROPE, AUS, NZ, ZA
Primary reduction system
Gear
←
Primary reduction ratio
57/17 (3.353)
←
Secondary reduction system
Chain drive
←
Secondary reduction ratio
49/13 (3.769)
51/13 (3.923)
Transmission type
Constant mesh, 5-speed
←
Operation
Left foot operation
←
30/14 (2.143)
←
2nd
28/16 (1.750)
←
3rd
26/18 (1.444)
←
4th
22/18 (1.222)
←
5th
25/24 (1.042)
←
Gear ratio:
1st
Chassis:
USA, CDN
EUROPE
AUS, NZ, ZA
Frame type
Bilateral beam
←
←
Caster angle
27.5°
27.2°
27.4°
Trail
120.2 mm (4.73
in)
117.4 mm (4.62
in)
119.6 mm (4.71
in)
Tire:
Type
With tube
Size (front)
80/100-21 51M
Size (rear)
100/90-19 57M
Tire pressure (front and rear)
100 kPa (1.0 kgf/cm2, 15 psi)
Brake:
Front brake type
Single disc brake
Operation
Right hand operation
Rear brake type
Single disc brake
Operation
Right foot operation
Suspension:
Front suspension
Telescopic fork
Rear suspension
Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber
Coil spring/oil damper
Rear shock absorber
Coil spring/gas, oil damper
Wheel travel:
USA, CDN
EUROPE, AUS, NZ, ZA
Front wheel travel
300 mm (11.8 in)
←
Rear wheel travel
307 mm (12.1 in)
310 mm (12.2 in)
Electrical:
Ignition system
CDI magneto
2-2
MAINTENANCE SPECIFICATIONS
MAINTENANCE SPECIFICATIONS
ENGINE
Item
Standard
Limit
Cylinder head:
Warp limit
----
0.05 mm (0.002
in)
Bore size
77.00–77.01 mm (3.0315–3.0319 in)
----
Out of round limit
----
0.05 mm (0.002
in)
Drive method
Chain drive (Left)
----
Camshaft cap inside diameter
22.000–22.021 mm (0.8661–0.8670 in)
----
Camshaft outside diameter
21.959–21.972 mm (0.8645–0.8650 in)
----
Shaft-to-cap clearance
0.028–0.062 mm (0.0011–0.0024 in)
0.08 mm (0.003
in)
Intake "A"
30.330–30.430 mm (1.1941–1.1980 in)
30.230 mm
(1.1902 in)
Intake "B"
22.45–22.55 mm (0.8839–0.8878 in)
22.35 mm
(0.8799 in)
Exhaust "A"
30.399–30.499 mm (1.1968–1.2007 in)
30.299 mm
(1.1929 in)
Exhaust "B"
22.45–22.55 mm (0.8839–0.8878 in)
22.35 mm
(0.8799 in)
Camshaft runout limit
----
0.03 mm
(0.0012 in)
Timing chain type/No. of links
92RH2010-114M/114
----
Timing chain adjustment method
Automatic
----
Cylinder:
Camshaft:
Cam dimensions
Timing chain:
2-3
MAINTENANCE SPECIFICATIONS
Item
Standard
Limit
Valve, valve seat, valve guide:
Valve clearance (cold)
IN
0.12–0.17 mm (0.0047–0.0067 in)
----
EX
0.17–0.22 mm (0.0067–0.0087 in)
----
"A" head diameter (IN)
22.9–23.1 mm (0.9016–0.9094 in)
----
"A" head diameter (EX)
24.4–24.6 mm (0.9606–0.9685 in)
----
"B" face width (IN)
2.26 mm (0.089 in)
----
"B" face width (EX)
2.26 mm (0.089 in)
----
"C" seat width (IN)
0.9–1.1 mm (0.0354–0.0433 in)
1.6 mm (0.0630
in)
"C" seat width (EX)
0.9–1.1 mm (0.0354–0.0433 in)
1.6 mm (0.0630
in)
"D" margin thickness (IN)
0.8 mm (0.0315 in)
----
"D" margin thickness (EX)
0.7 mm (0.0276 in)
----
Stem outside diameter (IN)
3.975–3.990 mm (0.1565–0.1571 in)
3.945 mm
(0.1553 in)
Stem outside diameter (EX)
4.460–4.475 mm (0.1756–0.1762 in)
4.430 mm
(0.1744 in)
Guide inside diameter (IN)
4.000–4.012 mm (0.1575–0.1580 in)
4.050 mm
(0.1594 in)
Guide inside diameter (EX)
4.500–4.512 mm (0.1772–0.1776 in)
4.550 mm
(0.1791 in)
Stem-to-guide clearance (IN)
0.010–0.037 mm (0.0004–0.0015 in)
0.08 mm (0.003
in)
Stem-to-guide clearance (EX)
0.025–0.052 mm (0.0010–0.0020 in)
0.10 mm (0.004
in)
Valve dimensions:
2-4
MAINTENANCE SPECIFICATIONS
Item
Standard
Limit
Stem runout limit
----
0.01 mm
(0.0004 in)
Valve seat width (IN)
0.9–1.1 mm (0.0354–0.0433 in)
1.6 mm (0.0630
in)
Valve seat width (EX)
0.9–1.1 mm (0.0354–0.0433 in)
1.6 mm (0.0630
in)
Free length (IN)
39.76 mm (1.57 in)
38.76 mm (1.53
in)
Free length (EX)
37.78 mm (1.49 in)
36.78 mm (1.45
in)
Set length (valve closed) (IN)
28.98 mm (1.14 in)
----
Set length (valve closed) (EX)
28.30 mm (1.11 in)
----
Compressed force (installed) (IN)
99–114 N at 28.98 mm (9.9–11.4 kg at
28.98 mm, 22.27–25.57 lb at 1.14 in)
----
Compressed force (installed) (EX)
126–145 N at 28.30 mm (12.6–14.5 kg at
28.30 mm, 28.44–31.97 lb at 1.11 in)
----
Tilt limit* (IN)
----
2.5°/1.7 mm
(2.5°/0.067 in)
Tilt limit* (EX)
----
2.5°/1.6 mm
(2.5°/0.063 in)
Direction of winding (top view) (IN)
Clockwise
----
Direction of winding (top view) (EX)
Clockwise
----
Piston to cylinder clearance
0.030–0.055 mm (0.0012–0.0022 in)
0.1 mm (0.004
in)
Piston size "D"
76.955–76.970 mm (3.0297–3.0303 in)
----
Measuring point "H"
8 mm (0.31 in)
----
Piston off-set
0.5 mm (0.020 in)/IN-side
----
Valve spring:
Piston:
2-5
MAINTENANCE SPECIFICATIONS
Item
Standard
Limit
Piston pin bore inside diameter
16.002–16.013 mm (0.6300–0.6304 in)
16.043 mm
(0.6316 in)
Piston pin outside diameter
15.991–16.000 mm (0.6296–0.6299 in)
15.971 mm
(0.6288 in)
Piston rings:
Top ring:
Type
Barrel
----
Dimensions (B × T)
0.90 × 2.75 mm (0.04 × 0.11 in)
----
End gap (installed)
0.15–0.25 mm (0.006–0.010 in)
0.50 mm (0.020
in)
Side clearance (installed)
0.030–0.065 mm (0.0012–0.0026 in)
0.12 mm (0.005
in)
Type
Taper
----
Dimensions (B × T)
0.80 × 2.75 mm (0.03 × 0.11 in)
----
End gap (installed)
0.30–0.45 mm (0.012–0.018 in)
0.80 mm (0.031
in)
Side clearance
0.020–0.055 mm (0.0008–0.0022 in)
0.12 mm (0.005
in)
Dimensions (B × T)
1.50 × 2.25 mm (0.06 × 0.09 in)
----
End gap (installed)
0.10–0.40 mm (0.004–0.016 in)
----
Crank width "A"
55.95–56.00 mm (2.203–2.205 in)
----
Runout limit "C"
0.03 mm (0.0012 in)
0.05 mm (0.002
in)
Big end side clearance "D"
0.15–0.45 mm (0.0059–0.0177 in)
0.50 mm (0.02
in)
Small end free play "F"
0.4–1.0 mm (0.016–0.039 in)
2.0 mm (0.08
in)
2nd ring:
Oil ring:
Crankshaft:
2-6
MAINTENANCE SPECIFICATIONS
Item
Standard
Limit
Clutch:
Friction plate thickness
Quantity
2.9–3.1 mm (0.114–0.122 in)
2.8 mm (0.110
in)
9
----
1.1–1.3 mm (0.043–0.051 in)
----
Quantity
8
----
Warp limit
----
0.1 mm (0.004
in)
35.7 mm (1.41 in)
34.7 mm (1.37
in)
5
----
Clutch housing thrust clearance
0.050–0.300 mm (0.0020–0.0118 in)
----
Clutch housing radial clearance
0.010–0.044 mm (0.0004–0.0017 in)
----
Clutch release method
Inner push, cam push
----
Clutch plate thickness
Clutch spring free length
Quantity
Shifter:
Shifter type
Cam drum and guide bar
----
Guide bar bending limit
----
0.05 mm (0.002
in)
Kickstarter:
Type
Kick and ratchet type
Carburetor:
USA, CDN
---EUROPE, AUS, NZ,
ZA
Type/manufacturer
FCR-MX37/KEIHIN
I. D. mark
17D5 50
17D6 60
----
Main jet (M.J)
#180
←
----
Main air jet (M.A.J)
ø2.0
←
----
Jet needle-clip position (J.N)
NDJR-4
NHKR-4
----
Cutaway (C.A)
1.5
←
----
Pilot jet (P.J)
#45
#42
----
Pilot air jet (P.A.J)
#105
←
----
Pilot outlet (P.O)
ø0.9
←
----
Pilot screw (example) (P.S)
1-3/4
←
----
Bypass (B.P)
ø1.0
←
----
Valve seat size (V.S)
ø3.8
←
----
Starter jet (G.S)
#72
←
----
Leak jet (Acc.P)
#70
#110
----
Float height (F.H)
8 mm (0.31 in)
←
----
Engine idle speed
1,900–2,100 r/min
←
----
Intake vacuum
29.3–34.7 kPa
(220–260 mmHg,
8.66–9.45 inHg)
←
----
Hot starter lever free play
3–6 mm (0.12–0.24 ←
in)
----
2-7
←
----
MAINTENANCE SPECIFICATIONS
Item
Standard
Limit
Lubrication system:
Oil filter type
Paper type
----
Oil pump type
Trochoid type
----
Tip clearance
0.12 mm or less (0.0047 in or less)
0.20 mm (0.008
in)
Side clearance
0.09–0.17 mm (0.0035–0.0067 in)
0.24 mm (0.009
in)
Housing and rotor clearance
0.03–0.10 mm (0.0012–0.0039 in)
0.17 mm
(0.0067 in)
Width
121.4 mm (4.8 in)
----
Height
235 mm (9.3 in)
----
Thickness
28 mm (1.1 in)
Cooling:
Radiator core size
---2,
Radiator cap opening pressure
110 kPa (1.1 kg/cm 15.6 psi)
----
Radiator capacity (total)
0.64 L (0.56 Imp qt, 0.68 US qt)
----
Single-suction centrifugal pump
----
Water pump
Type
CHASSIS
Item
Standard
Limit
Steering system:
Steering bearing type
Taper roller bearing
----
Front suspension:
USA, CDN
EUROPE, AUS, NZ, ZA
Front fork travel
300 mm (11.8 in)
←
----
Fork spring free length
454 mm (17.9 in)
←
449 mm (17.7
in)
Spring rate, STD
K = 4.4 N/mm (0.449 kg/ K = 4.5 N/mm (0.459 kg/ ---mm, 25.1 lb/in)
mm, 25.7 lb/in)
Optional spring
Yes
←
----
Oil capacity
541 cm3 (19.0 lmp oz,
18.3 US oz)
528 cm3 (18.6 lmp oz,
17.9 US oz)
----
Oil grade
Suspension oil "S1"
←
----
Inner tube outer diameter
48 mm (1.89 in)
←
----
Front fork top end
5 mm (0.20 in)
←
----
Rear suspension:
Shock absorber travel
USA, CDN
EUROPE, AUS, NZ, ZA
131.5 mm (5.18 in)
←
----
Spring free length
260 mm (10.24 in)
←
----
Fitting length
250 mm (9.84 in)
←
<Min.–Max.>
1.5–20 mm (0.06–0.79
in)
←
----
Spring rate, STD
K = 52.0 N/mm (5.30 kg/ ←
mm, 296.8 lb/in)
----
Optional spring
Yes
←
----
←
----
Preload length
Enclosed gas pressure
1,000 kPa (10 kg/cm
142 psi)
2-8
2,
MAINTENANCE SPECIFICATIONS
Item
Standard
Limit
Swingarm:
Swingarm free play limit
End
----
1.0 mm (0.04
in)
Front wheel type
Spoke wheel
----
Rear wheel type
Spoke wheel
----
Front rim size/material
21 × 1.60/Aluminum
----
Rear rim size/material
19 × 1.85/Aluminum
----
Radial
----
2.0 mm (0.08
in)
Lateral
----
2.0 mm (0.08
in)
Wheel:
Rim runout limit:
Drive chain:
USA, CDN
EUROPE, AUS, NZ, ZA
Type/manufacturer
DID520DMA2 SDH/
DAIDO
←
----
Number of links
111 links + joint
113 links + joint
----
Chain slack
50–60 mm (2.0–2.4 in)
←
----
Chain length (15 links)
----
←
242.9 mm
(9.563 in)
Front disc brake:
Disc outside dia.×Thickness
250 × 3.0 mm (9.84 × 0.12 in)
250 × 2.5 mm
(9.84 × 0.10 in)
Pad thickness
4.4 mm (0.17 in)
1.0 mm (0.04
in)
Master cylinder inside dia.
9.52 mm (0.375 in)
----
Caliper cylinder inside dia.
22.65 mm (0.892 in) × 2
----
Brake fluid type
DOT #4
----
Disc outside dia.×Thickness
245 × 4.0 mm (9.65 × 0.16 in)
245 × 3.5 mm
(9.65 × 0.14 in)
Deflection limit
----
0.15 mm
(0.006 in)
Pad thickness
6.4 mm (0.25 in)
1.0 mm (0.04
in)
Master cylinder inside dia.
11.0 mm (0.433 in)
----
Caliper cylinder inside dia.
25.4 mm (1.000 in) × 1
----
Brake fluid type
DOT #4
----
95 mm (3.74 in)
----
Rear disc brake:
Brake lever and brake pedal:
Brake lever position
Brake pedal height (vertical height above footrest Zero mm (Zero in)
top)
----
Clutch lever free play (lever end)
7–12 mm (0.28–0.47 in)
----
Throttle grip free play
3–5 mm (0.12–0.20 in)
----
2-9
TIGHTENING TORQUES
ELECTRICAL
Item
Standard
Limit
Ignition system:
Advancer type
Electrical
----
CDI:
Magneto-model (stator)/manufacturer
17D-50/YAMAHA
----
Charging coil 1 resistance (color)
720–1,080 Ωat 20 °C (68 °F)
(Green–Brown)
----
Charging coil 2 resistance (color)
44–66 Ωat 20 °C (68 °F) (Black–Pink)
----
Pickup coil resistance (color)
248–372 Ωat 20 °C (68 °F) (White–Red)
----
CDI unit-model/manufacturer
17D-50/YAMAHA (For USA and CDN)
----
17D-60/YAMAHA (Except for USA and
CDN)
----
Model/manufacturer
5UL-20/DENSO
----
Minimum spark gap
6 mm (0.24 in)
----
Primary coil resistance
0.08–0.10 Ωat 20 °C (68 °F)
----
Secondary coil resistance
4.6–6.8 kΩat 20 °C (68 °F)
----
Ignition coil:
TIGHTENING TORQUES
ENGINE
△ - marked portion shall be checked for torque tightening after break-in or before each race.
Part to be tightened
Spark plug
Thread size
Q'ty
Tightening torque
Nm
m•kg
ft•lb
M10S × 1.0
1
13
1.3
9.4
Camshaft cap
M6 × 1.0
10
10
1.0
7.2
Cylinder head blind plug screw
M12 × 1.0
1
28
2.8
20
Cylinder head (stud bolt)
M6 × 1.0
2
7
0.7
5.1
Cylinder head (stud bolt)
M8 × 1.25
1
15
1.5
11
Cylinder head (bolt)
M9 × 1.25
4
38
3.8
27
Cylinder head (nut)
M6 × 1.0
2
10
1.0
7.2
Cylinder head cover
M6 × 1.0
2
10
1.0
7.2
Cylinder
M6 × 1.0
1
10
1.0
7.2
Balancer weight
M6 × 1.0
2
10
1.0
7.2
Balancer shaft driven gear
M14 × 1.0
1
50
5.0
36
Timing chain guide (intake side)
M6 × 1.0
2
10
1.0
7.2
Timing chain tensioner
M6 × 1.0
2
10
1.0
7.2
Timing chain tensioner cap bolt
M6 × 1.0
1
7
0.7
5.1
Impeller
M8 × 1.25
1
14
1.4
10
Radiator hose clamp
M6 × 1.0
10
2
0.2
1.4
Coolant drain bolt
M6 × 1.0
1
10
1.0
7.2
Water pump housing
M6 × 1.0
4
10
1.0
7.2
Radiator
M6 × 1.0
6
10
1.0
7.2
Radiator pipe
M6 × 1.0
1
10
1.0
7.2
Oil pump cover
M4 × 0.7
1
1.7
0.17
1.2
Oil pump
M6 × 1.0
3
10
1.0
7.2
2-10
TIGHTENING TORQUES
Part to be tightened
△
△
Thread size
Q'ty
Oil filter element drain bolt
M6 × 1.0
Oil filter element cover
Tightening torque
Nm
m•kg
ft•lb
1
10
1.0
7.2
M6 × 1.0
2
10
1.0
7.2
Oil strainer (crankcase)
M6 × 1.0
2
10
1.0
7.2
Oil delivery pipe 1 (M10)
M10 × 1.25
1
20
2.0
14
Oil delivery pipe 1 (M8)
M8 × 1.25
2
18
1.8
13
Oil hose
M6 × 1.0
2
8
0.8
5.8
Oil hose clamp
—
1
2
0.2
1.4
Oil strainer (oil tank)
M6 × 1.0
1
9
0.9
6.5
Oil tank drain bolt
M8 × 1.25
1
18
1.8
13
Oil tank (upper)
M6 × 1.0
1
4
0.4
2.9
Oil tank and frame
M6 × 1.0
3
9
0.9
6.5
Carburetor joint clamp
M5 × 0.8
1
3
0.3
2.2
Air filter joint clamp
M6 × 1.0
1
3
0.3
2.2
Throttle cable adjust bolt and locknut
M6 × 0.75
1
4
0.4
2.9
Throttle cable (pull)
M6 × 1.0
1
4
0.4
2.9
Throttle cable (return)
M12 × 1.0
1
11
1.1
8.0
Throttle cable cover
M5 × 0.8
2
4
0.4
2.9
Hot starter plunger
M12 × 1.0
1
2
0.2
1.4
Hot starter cable adjust bolt and locknut
M6 × 0.75
1
4
0.4
2.9
Air filter case
M6 × 1.0
2
8
0.8
5.8
Air filter joint and air filter case
M5 × 0.8
1
4
0.4
2.9
Air filter element
M6 × 1.0
1
2
0.2
1.4
Exhaust pipe
M8 × 1.25
2
20
2.0
14
△
Exhaust pipe protector
M6 × 1.0
3
10
1.0
7.2
△
Silencer
M8 × 1.25
2
30
3.0
22
Silencer clamp
M8 × 1.25
1
14
1.4
10
Crankcase
M6 × 1.0
11
12
1.2
8.7
Crankcase bearing stopper
M6 × 1.0
11
10
1.0
7.2
Crankcase bearing stopper (crankshaft)
M6 × 1.0
4
14
1.4
10
Left crankcase cover
M6 × 1.0
8
10
1.0
7.2
Right crankcase cover
M6 × 1.0
8
10
1.0
7.2
Clutch cover
M6 × 1.0
7
10
1.0
7.2
Crankcase oil drain bolt
M10 × 1.25
1
20
2.0
14
△
Crankshaft end accessing screw
M32 × 1.5
1
—
—
—
△
Timing mark accessing screw
M14 × 1.5
1
—
—
—
△
Drive chain sprocket cover
M6 × 1.0
2
7
0.7
5.1
Kick shaft ratchet wheel guide
M6 × 1.0
2
12
1.2
8.7
Kickstarter crank
M8 × 1.25
1
33
3.3
24
Primary drive gear
M18 × 1.0
1
75
7.5
54
Clutch spring
M6 × 1.0
5
10
1.0
7.2
Clutch boss
M16 × 1.0
1
75
7.5
54
Clutch cable locknut
M8 × 1.25
1
7
0.7
5.1
Clutch cable adjust bolt and locknut
M6 × 0.75
1
4
0.4
2.9
Push lever shaft
M6 × 1.0
1
10
1.0
7.2
2-11
TIGHTENING TORQUES
Part to be tightened
Thread size
Q'ty
Drive sprocket
M18 × 1.0
Drive axle oil seal stopper
Tightening torque
Nm
m•kg
ft•lb
1
75
7.5
54
M6 × 1.0
2
10
1.0
7.2
Segment
M8 × 1.25
1
30
3.0
22
Shift guide
M6 × 1.0
2
10
1.0
7.2
Stopper lever
M6 × 1.0
1
10
1.0
7.2
Shift pedal
M6 × 1.0
1
12
1.2
8.7
CHASSIS
△ - marked portion shall be checked for torque tightening after break-in or before each race.
Part to be tightened
Thread size
Q'ty
Tightening torque
Nm
m•kg
ft•lb
△
Upper bracket and outer tube
M8 × 1.25
4
21
2.1
15
△
Lower bracket and outer tube
M8 × 1.25
4
21
2.1
15
△
Upper bracket and steering stem
M24 × 1.0
1
145
14.5
105
△
Handlebar upper holder and handlebar lower holder
M8 × 1.25
4
28
2.8
20
△
Handlebar lower holder and upper bracket
M10 × 1.25
2
34
3.4
25
△
Steering stem and steering ring nut
M28 × 1.0
1
Front fork and damper assembly
M51 × 1.5
2
Front fork and adjuster
M22 × 1.25
2
55
5.5
40
Damper assembly and base valve
M42 × 1.5
2
29
2.9
21
Adjuster and damper assembly
M12 × 1.25
2
29
2.9
21
M5 × 0.8
2
1
0.1
0.7
Front fork bleed screw and base valve
Refer to TIP.
30
3.0
22
△
Front fork and front fork protector
M6 × 1.0
6
5
0.5
3.6
△
Lower bracket and brake hose guide
M6 × 1.0
1
9
0.9
6.5
△
Front fork protector and brake hose holder
M6 × 1.0
2
8
0.8
5.8
Throttle grip cap
M5 × 0.8
2
4
0.4
2.9
Front brake master cylinder
M6 × 1.0
2
9
0.9
6.5
Brake lever mounting bolt
M6 × 1.0
1
6
0.6
4.3
Brake lever mounting nut
M6 × 1.0
1
6
0.6
4.3
Brake lever position locknut
M6 × 1.0
1
5
0.5
3.6
△
Clutch lever holder
M6 × 1.0
2
5
0.5
3.6
Clutch lever mounting nut
M6 × 1.0
1
4
0.4
2.9
Clutch lever position lock nut
M5 × 0.8
1
5
0.5
3.6
Hot starter lever holder
M5 × 0.8
2
4
0.4
2.9
M4 × 0.7
2
2
0.2
1.4
△
Front brake master cylinder cap
Front brake hose union bolt
M10 × 1.25
2
30
3.0
22
△
Front brake caliper
M8 × 1.25
2
28
2.8
20
Pad pin plug
M10 × 1.0
2
3
0.3
2.2
△
Front brake caliper and pad pin
M10 × 1.0
1
18
1.8
13
△
Rear brake caliper and pad pin
M10 × 1.0
1
18
1.8
13
△
Brake caliper and bleed screw
M8 × 1.25
2
6
0.6
4.3
△
Front wheel axle and axle nut
M16 × 1.5
1
105
10.5
75
△
Front wheel axle holder
M8 × 1.25
4
21
2.1
15
2-12
TIGHTENING TORQUES
Part to be tightened
Thread size
Q'ty
Tightening torque
Nm
m•kg
ft•lb
△
Front brake disc
M6 × 1.0
6
12
1.2
8.7
△
Rear brake disc
M6 × 1.0
6
14
1.4
10
△
Footrest bracket and frame
M10 × 1.25
4
55
5.5
40
△
Brake pedal
M8 × 1.25
1
26
2.6
19
△
Rear brake master cylinder
M6 × 1.0
2
10
1.0
7.2
Rear brake master cylinder cap
M4 × 0.7
2
2
0.2
1.4
△
Rear brake hose union bolt
M10 × 1.25
2
30
3.0
22
△
Rear wheel axle and axle nut
M22 × 1.5
1
135
13.5
98
△
Nipple (spoke)
—
72
3
0.3
2.2
△
Rear wheel sprocket
M8 × 1.25
6
42
4.2
30
△
Rear brake disc cover
M6 × 1.0
2
10
1.0
7.2
△
Rear brake caliper protector
M6 × 1.0
2
7
0.7
5.1
Drive chain puller adjust bolt and locknut
M8 × 1.25
2
21
2.1
15
Engine mounting:
△
Engine and engine bracket (front)
M10 × 1.25
1
53
5.3
38
△
Engine and frame (lower)
M10 × 1.25
1
53
5.3
38
△
Upper engine bracket and frame
M8 × 1.25
4
34
3.4
25
△
Front engine bracket and frame
M8 × 1.25
4
34
3.4
25
△
Engine and engine bracket (upper)
M10 × 1.25
2
55
5.5
40
Lower engine guard
M6 × 1.0
3
10
1.0
7.2
CDI unit bracket
M6 × 1.0
2
7
0.7
5.1
Cable guide and frame
M6 × 1.0
2
7
0.7
5.1
△
Pivot shaft and nut
M16 × 1.5
1
85
8.5
61
△
Relay arm and swingarm
M14 × 1.5
1
70
7.0
50
△
Relay arm and connecting rod
M14 × 1.5
1
80
8.0
58
△
Connecting rod and frame
M14 × 1.5
1
80
8.0
58
△
Rear shock absorber and frame
M10 × 1.25
1
56
5.6
40
△
Rear shock absorber and relay arm
M10 × 1.25
1
53
5.3
38
△
Rear frame (upper)
M8 × 1.25
2
32
3.2
23
△
Rear frame (lower)
M8 × 1.25
2
32
3.2
23
△
Swingarm and brake hose holder
M5 × 0.8
4
3
0.3
2.2
Upper drive chain tensioner
M8 × 1.25
1
16
1.6
11
Lower drive chain tensioner
M8 × 1.25
1
16
1.6
11
Drive chain support
M6 × 1.0
3
7
0.7
5.1
△
Seal guard and swingarm
M5 × 0.8
4
6
0.6
4.3
△
Fuel tank
M6 × 1.0
1
9
0.9
6.5
△
Fuel cock
M6 × 1.0
2
4
0.4
2.9
Seat set bracket and fuel tank
M6 × 1.0
1
7
0.7
5.1
Fuel tank bracket and fuel tank
M6 × 1.0
2
7
0.7
5.1
Side cover set bracket and fuel tank
M6 × 1.0
2
7
0.7
5.1
Fitting band set screw and fuel tank
M6 × 1.0
1
7
0.7
5.1
△
Air scoop and fuel tank
M6 × 1.0
2
7
0.7
5.1
△
Air scoop and radiator guard
M6 × 1.0
4
7
0.7
5.1
Air scoop and frame
M6 × 1.0
2
7
0.7
5.1
2-13
TIGHTENING TORQUES
Part to be tightened
Radiator mounting boss and frame
Thread size
Q'ty
M10 × 1.25
M6 × 1.0
Tightening torque
Nm
m•kg
ft•lb
2
20
2.0
14
4
10
1.0
7.2
△
Front fender
△
Rear fender (front)
M6 × 1.0
2
7
0.7
5.1
△
Rear fender (rear)
M6 × 1.0
2
16
1.6
11
△
Side cover
M6 × 1.0
2
7
0.7
5.1
Seat
M8 × 1.25
2
23
2.3
17
Number plate
M6 × 1.0
1
7
0.7
5.1
△
1. First, tighten the steering ring nut approximately 38 Nm (3.8 m•kg, 27 ft•lb) by using the steering nut wrench, then loosen
the steering ring nut one turn.
2. Retighten the steering ring nut 7 Nm (0.7 m•kg, 5.1 ft•lb).
ELECTRICAL
Part to be tightened
Tightening torque
Thread size
Q'ty
Nm
m•kg
ft•lb
Stator
M6 × 1.0
3
10
1.0
7.2
Rotor
M12 × 1.25
1
56
5.6
40
M5 × 0.8
2
4
0.4
2.9
Neutral switch
2-14
TIGHTENING TORQUES
GENERAL TORQUE
SPECIFICATIONS
This chart specifies torque for standard fasteners with standard I.S.O.
pitch threads. Torque specifications
for special components or assemblies are included in the applicable
sections of this book. To avoid warpage, tighten multi-fastener assemblies in a crisscross fashion, in
progressive stages, until full torque is
reached. Unless otherwise specified,
torque specifications call for clean,
dry threads. Components should be
at room temperature.
B
A
(Bolt
(Nut)
)
A. Distance between flats
B. Outside thread diameter
TORQUE SPECIFICATION
Nm
m•kg
ft•lb
10
mm
6 mm
6
0.6
4.3
12
mm
8 mm
15
1.5
11
14
mm
10
mm
30
3.0
22
17
mm
12
mm
55
5.5
40
19
mm
14
mm
85
8.5
61
22
mm
16
mm
130
13
94
DEFINITION OF UNITS
Unit
Read
Definition
-3
Measure
millimeter
10 meter
Length
cm
centimeter
10-2
Length
kg
kilogram
103 gram
mm
meter
Weight
2
N
Newton
1 kg × m/sec
Nm
Newton meter
N×m
Torque
m•kg
Meter kilogram
m × kg
Torque
2
Force
Pa
Pascal
N/m
Pressure
N/mm
Newton per millimeter
N/mm
L
Liter
cm3
Cubic centimeter
—
Volume or capacity
r/min
Revolution per minute
—
Engine speed
Spring rate
—
2-15
Volume or capacity
LUBRICATION DIAGRAMS
LUBRICATION DIAGRAMS
1.
2.
3.
4.
5.
6.
7.
8.
A.
Oil filter element
Oil pump
Drive axle
Main axle
Intake camshaft
Exhaust camshaft
Oil tank
Oil delivery pipe
To oil tank
2-16
LUBRICATION DIAGRAMS
1.
2.
3.
4.
A.
Crankshaft
Oil filter element
Oil tank
Oil hose
From oil pump
2-17
CABLE ROUTING DIAGRAM
CABLE ROUTING DIAGRAM
C
C
A
A
B
B
1.
2.
3.
4.
5.
6.
7.
8.
9.
Fuel tank breather hose
Radiator hose 1
Cylinder head breather hose
Radiator hose 3
Clutch cable
Throttle position sensor lead
Hot starter cable
Fuel hose
Carburetor breather hose
10. Carburetor overflow hose
11. Throttle position sensor lead
protector
12. Throttle position sensor cover
2-18
A.
B.
Insert the end of the fuel tank
breather hose into the hole in
the steering stem.
Aligh the paint mark on the cylinder head breather hose with the
front end of the hose guide.
CABLE ROUTING DIAGRAM
C.
D.
E.
F.
G.
Pass the cylinder head breather
hose on the outside of front engine bracket.
Pass the cylinder head breather
hose between the radiator and
radiator hose 3.
Pass the fuel hose on the outside of throttle position sensor
lead.
Pass the carburetor breather
hoses and overflow hose so that
all there hoses do not contact
the rear shock absorber.
Insert the throttle position sensor lead protector into the throttle position sensor cover.
2-19
CABLE ROUTING DIAGRAM
I
F-F
J
B
A-A
A
C
B
L
A
C
M
D
J
H-H
L
M-M
D
I
K
K
G
D-D
H
H
K-K
M
F
G
F
E
E
E-E
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Sub-wire harness
Hot starter cable
Oil hose
Neutral switch lead
Radiator hose 2
Clamp
Ignition coil lead
CDI magneto lead
Neutral switch lead coupler
CDI unit lead coupler
11.
12.
13.
14.
15.
16.
Radiator breather hose
Hot starter cable protector
Rubber cap
Throttle position sensor lead
Cylinder head breather hose
Throttle position sensor lead
coupler
17. Tension pipe
18. Radiator mounting boss
19. Cylinder head breather hose
2-20
20. Throttle position sensor tube
clamp
CABLE ROUTING DIAGRAM
A.
B.
C.
D.
E.
F.
G.
H.
I.
J.
K.
L.
M.
N.
O.
P.
Q.
Pass the hot starter cable over
the radiator mounting boss.
Pass the throttle position sensor
lead under the hot starter cable.
Fasten the throttle position sensor lead and the hot starter cable.
Locate the clamp between the
hot starter cable protector and
rubber cap.
Fasten the neutral switch lead
below the oil hose. and pass the
neutral switch lead on the inside
of the oil hose.
Pass the neutral switch lead on
the inside of the oil hose.
Fasten the neutral switch lead,
CDI magneto lead, and radiator
breather hose onto the frame.
They should all be clamped
above the engine bracket to the
left of the downtube of the
frame. The clamp ends should
face backward and the rest outside of the frame.
Pass the clutch cable through
the cable guide.
Pass the neutral switch lead and
CDI magneto lead behind the
frame.
Pass the hot starter cable on the
inside of the cylinder head
breather hose.
Fit the coupler projection into the
hole in the cover.
Fasten the sub-wire harness on
the CDI unit bracket.
Fasten the sub-wire harness at
the position-taped portion.
Pass each lead under the
clamp. Locate the CDI magneto
lead on the outside of the ignition coil lead. Locate the throttle
position sensor lead, neutral
switch lead, CDI magneto lead
and ignition coil lead so that they
do not lie one on another.
Fasten the sub-wire harness to
the CDI unit bracket with the
clamp ends located under the
bracket.
Fasten the neutral switch lead,
throttle position sensor lead,
CDI magneto lead and ignition
coil lead. Fasten them around
the periphery of the recess between the tension pipe and radiator mounting boss on the
frame.
Locate the clamp ends within
the arrowed range. Assure that
the clamp end does not contact
the cylinder head breather hose.
R.
S.
T.
U.
Pass the radiator breather hose
on the outside of the CDI magneto lead and neutral switch
lead.
Fasten the throttle position sensor lead and hot starter cable.
Fasten them between the cylinder head breather hose and
throttle position sensor tube
clamp. Fasten the clamp with its
ends toward the right-side of the
frame and cut off the other end
with 3 to 5 clamp holes left in it.
Locate the radiator breather
hose end above the down tube
and between the oil hose and
engine guard.
Fasten the neutral switch lead
above the oil hose, and pass the
neutral switch lead on the inside
of the oil hose.
2-21
CABLE ROUTING DIAGRAM
B
A
C
C
B
A
1.
2.
3.
4.
5.
6.
Radiator hose 2
Radiator breather hose
Ignition coil
Throttle cable (pull)
Throttle cable (return)
Engine stop switch lead
A.
B.
C.
D.
Put a cover over the ignition coil.
Pass the throttle cables through
the cable guide.
Pass the throttle cable over the
radiator mounting boss. Cross
the throttle cable behind the radiator.
Pass the throttle cables on the
outside of the ignition coil.
2-22
E.
F.
Insert the engine stop switch
lead into the CDI unit band.
Align the coupler lower end with
the band lower end.
Fit the hole in the CDI unit band
over the CDI unit bracket.
CABLE ROUTING DIAGRAM
1.
2.
3.
Brake master cylinder
Brake hose holder
Brake hose
A.
B.
Install the brake hose so that its
pipe portion directs as shown
and lightly touches the projection on the brake caliper.
Pass the brake hose into the
brake hose holders.
2-23
C.
D.
If the brake hose contacts the
spring (rear shock absorber),
correct its twist.
Install the brake hose so that its
pipe portion directs as shown
and lightly touches the projection on the brake master cylinder.
CABLE ROUTING DIAGRAM
A
B
C
A
B
C
1.
2.
3.
4.
5.
6.
7.
8.
Throttle cable
Clamp
Hot starter cable
Clutch cable
Engine stop switch lead
Cable guide
Brake hose
Hose guide
A.
B.
C.
Fasten the engine stop switch
lead to the handlebar.
Pass the clutch cable and hot
starter cable through the cable
guide.
Pass the engine stop switch
lead behind the CDI unit.
D.
E.
F.
G.
2-24
Pass the brake hose in front of
the number plate.
Pass the throttle cables through
the cable guide.
Pass the clutch cable and hot
starter cable through the cable
guide on the number plate.
Pass the engine stop switch
lead over the number plate
mounting location.
MAINTENANCE INTERVALS
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
• The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind that such factors as
weather, terrain, geographical location, and individual usage will alter the required maintenance and lubrication intervals.
If you are a doubt as to what intervals to follow in maintaining and lubricating your machine, consult your Yamaha dealer
• Periodic inspection is essential in making full use of the machine performance. The service life of the parts varies substantially according to the environment in which the machine runs (e.g., rain, dirt, etc.). Therefore, earlier inspection is
required by reference to the list below.
Item
After
breakin
Every
race
(about
2.5
hours)
Every
third
(about
7.5
hours)
Every
fifth
(about
12.5
hours)
As required
Remarks
ENGINE OIL
Replace
●
Inspect
3
●
●
●
OIL FILTER ELEMENT, OIL
STRAINER
Clean
●
VALVES
Check the valve clearances
●
The engine must be cold.
●
Inspect
Check the valve seats and valve
stems for wear.
●
Replace
●
VALVE SPRINGS
Inspect
Check the free length and the tilt.
●
Replace
●
VALVE LIFTERS
Inspect
Check for scratches and wear.
●
Replace
●
CAMSHAFTS
Inspect the camshaft surface.
Inspect
Inspect the decompression system.
●
Replace
●
TIMING CHAIN SPROCKETS,
TIMING CHAIN
Inspect
Check for wear on the teeth and for
damage.
●
Replace
●
PISTON
Inspect
●
Inspect crack.
Clean
●
Inspect carbon deposits and eliminate
them.
Replace
●
It is recommended that the piston pin
and ring are also replaced at the same
time.
●
PISTON RING
Inspect
●
Replace
●
3-1
Check ring end gap.
●
MAINTENANCE INTERVALS
Item
After
breakin
Every
race
(about
2.5
hours)
Every
third
(about
7.5
hours)
Every
fifth
(about
12.5
hours)
As required
Remarks
PISTON PIN
Inspect
●
Replace
●
CYLINDER HEAD
Inspect carbon deposits and eliminate
them.
Inspect and clean
●
Change gasket.
●
Inspect score marks.
CYLINDER
Inspect and clean
Replace
●
Inspect wear.
CLUTCH
Inspect and adjust
●
Inspect housing, friction plate, clutch
plate and spring.
●
Replace
●
TRANSMISSION
Inspect
●
Replace bearing
●
SHIFT FORK, SHIFT CAM,
GUIDE BAR
Inspect
●
Inspect wear.
ROTOR NUT
Retighten
●
●
EXHAUST PIPE, SILENCER,
PROTECTOR
Inspect and retighten
●
●
Clean
●
Replace
●
Replace fiber
●*
●
* When the exhaust sound becomes
louder or when a performance drop is
felt
CRANK
Inspect and clean
●
●
CARBURETOR
Inspect, adjust and clean
●
●
SPARK PLUG
Inspect and clean
●
●
Replace
●
DRIVE CHAIN
Lubricate, slack, alignment
Use chain lube.
●
Chain slack: 50–60 mm (2.0–2.4 in)
●
Replace
●
3-2
MAINTENANCE INTERVALS
Item
After
breakin
Every
race
(about
2.5
hours)
●
●
Every
third
(about
7.5
hours)
Every
fifth
(about
12.5
hours)
As required
Remarks
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
●
Replace coolant
●
Inspect hoses
Every two years
●
OUTSIDE NUTS AND BOLTS
Retighten
●
●
Refer to "STARTING AND BREAKIN" section in the CHAPTER 1.
●
●
Use foam air-filter oil or equivalent oil.
AIR FILTER
Clean and lubricate
Replace
●
OIL FILTER
Replace
●
●
OIL STRAINER
Clean
●
ENGINE GUARD
Replace
●
Breakage
FRAME
Clean and inspect
●
●
FUEL TANK, COCK
Clean and inspect
●
●
BRAKES
Adjust lever position and pedal
height
●
●
Lubricate pivot point
●
●
Check brake disc surface
●
●
Check fluid level and leakage
●
●
Retighten brake disc bolts, caliper bolts, master cylinder bolts
and union bolts
●
●
Replace pads
●
Replace brake fluid
●
Every one year
FRONT FORKS
Inspect and adjust
●
Replace oil
●
●
Suspension oil "S1"
●
Replace oil seal
●
FRONT FORK OIL SEAL AND
DUST SEAL
Clean and lube
●
Lithium base grease
●
PROTECTOR GUIDE
Replace
●
3-3
MAINTENANCE INTERVALS
Item
After
breakin
Every
race
(about
2.5
hours)
●
●
Every
third
(about
7.5
hours)
Every
fifth
(about
12.5
hours)
As required
Remarks
REAR SHOCK ABSORBER
Inspect and adjust
Lube
(After
rain
ride) ● Molybdenum disulfide grease
●
Replace spring seat
Retighten
●
Every one year
●
●
●
●
●
●
Molybdenum disulfide grease
●
●
Molybdenum disulfide grease
●
●
DRIVE CHAIN GUIDE AND
ROLLERS
Inspect
SWINGARM
Inspect, lube and retighten
RELAY ARM, CONNECTING
ROD
Inspect, lube and retighten
STEERING HEAD
Inspect free play and retighten
Clean and lube
Lithium base grease
●
Replace bearing
●
TIRE, WHEELS
Inspect air pressure, wheel runout, tire wear and spoke looseness
●
●
Retighten sprocket bolt
●
●
Inspect bearings
●
Replace bearings
●
Lubricate
Lithium base grease
●
THROTTLE, CONTROL CABLE
Check routing and connection
●
●
Lubricate
●
●
Yamaha cable lube or SAE 10W-40
motor oil
Inspect and clean (throttle cable)
●
●
Inspect dirt and wear on the throttle
cable on the carburetor side.
HOT STARTER, CLUTCH LEVER
Inspect free play
●
3-4
PRE-OPERATION INSPECTION AND MAINTENANCE
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item
Routine
Page
Coolant
Check that coolant is filled up to the radiator cap. Check the cooling system for leakage.
P.3-6 – 7
Fuel
Check that a fresh gasoline is filled in the fuel tank. Check the fuel
line for leakage.
P.1-13
Engine oil
Check that the oil level is correct. Check the crankcase and oil line
for leakage.
P.3-9 – 10
Gear shifter and clutch
Check that gears can be shifted correctly in order and that the
clutch operates smoothly.
Throttle grip/Housing
Check that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.
P.3-7 – 8
Brakes
Check the play of front brake and effect of front and rear brake.
P.3-14 – 16
Drive chain
Check drive chain slack and alignment. Check that the drive chain
is lubricated properly.
P.3-17 – 18
Wheels
Check for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.
P.3-20 – 21
Steering
Check that the handlebar can be turned smoothly and have no excessive play.
P.3-21 – 22
Front forks and rear shock
absorber
Check that they operate smoothly and there is no oil leakage.
P.3-7
P.3-18 – 20
Cables (wires)
Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or when
the front forks travel up and down.
—
Exhaust pipe
Check that the exhaust pipe is tightly mounted and has no cracks.
P.4-3 – 4
Rear wheel sprocket
Check that the rear wheel sprocket tightening bolt is not loose.
P.3-17
Lubrication
Check for smooth operation. Lubricate if necessary.
P.3-23
Bolts and nuts
Check the chassis and engine for loose bolts and nuts.
P.1-15
Lead connectors
Check that the CDI magneto, CDI unit, and ignition coil are connected tightly.
P.1-7
Settings
Is the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs before racing? Are inspection and maintenance completely done?
P.7-1 – 10
3-5
ENGINE
ENGINE
CHECKING THE COOLANT LEVEL
Do not remove the radiator cap
"1", drain bolt and hoses when the
engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which
could cause serious injury. When
the engine has cooled, place a
thick towel over the radiator cap,
slowly rotate the cap counterclockwise to the detent. This procedure allows any residual
pressure to escape. When the
hissing sound has stopped, press
down on the cap while turning
counterclockwise and remove it.
Hard water or salt water is harmful
to the engine parts. You may use
distilled water, if you can't get soft
water.
1. Place a container under the engine.
2. Remove:
• Coolant drain bolt "1"
3. Remove:
• Radiator cap
Drain the coolant completely.
4. Clean:
• Cooling system
Thoroughly flush the cooling system with clean tap water.
5. Install:
• Copper washer
• Coolant drain bolt
Coolant drain bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)
6. Fill:
• Radiator
• Engine
To specified level.
1. Place the machine on a level
place, and hold it in an upright position.
2. Remove:
• Radiator cap
3. Check:
• Coolant level "a"
Coolant level low → Add coolant.
1. Radiator
CHANGING THE COOLANT
Recommended coolant:
High quality ethylene
glycol anti-freeze containing anti-corrosion
for aluminum engine
Coolant "1" and water
(soft water) "2" mixing ratio:
50%/50%
Coolant capacity:
1.00 L (0.88 Imp qt, 1.06
US qt)
• Do not mix more than one type of
ethylene glycol antifreeze containing corrosion inhibitors for
aluminum engine.
• Do not use water containing impurities or oil.
Do not remove the radiator cap
when the engine is hot.
Handling notes of coolant:
The coolant is harmful so it should be
handled with special care.
• When coolant splashes to your
eye.
Thoroughly wash your eye with
water and see your doctor.
• When coolant splashes to your
clothes.
Quickly wash it away with water
and then with soap.
• When coolant is swallowed.
Quickly make him vomit and take
him to a doctor.
7. Install:
• Radiator cap
Start the engine and warm it up
for a several minutes.
8. Check:
• Coolant level
Coolant level low → Add coolant.
CHECKING THE RADIATOR CAP
1. Inspect:
• Seal (radiator cap) "1"
• Valve and valve seat "2"
Crack/damage → Replace.
Exist fur deposits "3" → Clean or
replace.
CHECKING THE RADIATOR CAP
OPENING PRESSURE
1. Attach:
• Radiator cap tester "1" and adapter "2"
Radiator cap tester:
YU-24460-01/9089001325
Radiator cap tester
adapter:
YU-33984/90890-01352
Apply water on the radiator cap seal.
Take care so that coolant does not
splash on painted surfaces. If it
splashes, wash it away with water.
3-6
ENGINE
3. Radiator cap
2. Apply the specified pressure.
Radiator cap opening
pressure:
110 kPa (1.1 kg/cm2,
15.6 psi)
3. Inspect:
• Pressure
Impossible to maintain the specified pressure for 10 seconds →
Replace.
CHECKING THE COOLING
SYSTEM
1. Inspect:
• Coolant level
2. Attach:
• Radiator cap tester "1" and adapter "2"
Radiator cap tester:
YU-24460-01/9089001325
Radiator cap tester
adapter:
YU-33984/90890-01352
ADJUSTING THE CLUTCH LEVER
POSITION
1. Adjust:
• Clutch lever position
Clutch lever position adjustment
steps:
a. Loosen the locknuts "1".
b. Turn the adjusting bolt "2" until the
clutch lever position "a" is in the
desiered position .
Locknut:
4 Nm (0.4 m•kg, 2.9
ft•lb)
• Before adjustment, expose the adjuster by moving the boot "3" and
cap "4" away.
• Make minute adjustment on the lever side using the adjuster "5".
• After adjustment, check proper operation of clutch lever.
c. Tighten the locknuts.
Locknut:
5 Nm (0.5 m•kg, 3.6
ft•lb)
3. Apply the specified pressure.
2. Adjust:
• Clutch cable free play
Refer to "ADJUSTING THE
CLUTCH CABLE FREE PLAY".
ADJUSTING THE CLUTCH CABLE
FREE PLAY
1. Check:
• Clutch lever free play "a"
Out of specification → Adjust.
Standard pressure:
180 kPa (1.8 kg/cm2,
25.6 psi)
Clutch lever free play "a"
:
7–12 mm (0.28–0.47 in)
• Do not apply pressure more than
specified pressure.
• Radiator should be filled fully.
4. Inspect:
• Pressure
Impossible to maintain the specified pressure for 10 seconds →
Repair.
• Radiator "1"
• Radiator hose joint "2"
Coolant leakage → Repair or replace.
• Radiator hose "3"
Swelling → Replace.
Clutch lever free play adjustment
steps:
a. Loosen the locknuts "1".
b. Turn the adjuster "2" until free
play "a" is within the specified limits.
c. Tighten the locknuts.
3. Install:
• Cap "1"
• Boot "2"
Place the tip "a" of the cap in the boot.
ADJUSTING THE THROTTLE
CABLE FREE PLAY
1. Check:
• Throttle grip free play "a"
Out of specification → Adjust.
Throttle grip free play
"a":
3–5 mm (0.12–0.20 in)
2. Adjust:
• Clutch lever free play
3-7
ENGINE
2. Adjust:
• Throttle grip free play
Throttle grip free play adjustment
steps:
a. Slide the adjuster cover.
b. Loosen the locknut "1".
c. Turn the adjuster "2" until the
specified free play is obtained.
d. Tighten the locknut.
Locknut:
4 Nm (0.4 m•kg, 2.9
ft•lb)
Before adjusting the throttle cable
free play, the engine idle speed
should be adjusted.
After adjusting the throttle cable
free play, start the engine and turn
the handlebar to right and left and
make sure that the engine idling
does not run faster.
3. Install:
• Throttle grip cap
• Screw (throttle grip cap)
Screw (throttle grip cap):
4 Nm (0.4 m•kg, 2.9
ft•lb)
• Cover (grip cap)
• Cover (throttle cable cap)
ADJUSTING THE HOT STARTER
LEVER FREE PLAY
1. Check:
• Hot starter lever free play "a"
Out of specification → Adjust.
Hot starter lever free play
"a":
3–6 mm (0.12–0.24 in)
Remove:
Seat
Fitting bolt "1"
Washer "2"
Air filter element "3"
Air filter guide "4"
2. Clean:
• Air filter element
Clean them with solvent.
2. Adjust:
• Hot starter lever free play
After cleaning, remove the remaining
solvent by squeezing the element.
Hot starter lever free play adjustment steps:
a. Loosen the locknut "1".
b. Turn the adjuster "2" until free
play "a" is within the specified limits.
c. Tighten the locknut.
• Do not twist the element when
squeezing the element.
• Leaving too much of solvent in
the element may result in poor
starting.
Locknut:
4 Nm (0.4 m•kg, 2.9
ft•lb)
After adjustment, check proper operation of hot starter.
LUBRICATING THE THROTTLE
1. Remove:
• Cover (throttle cable cap) "1"
• Cover (grip cap) "2"
• Throttle grip cap "3"
2. Apply:
• Lithium soap base grease
On the throttle cable end "a".
1.
•
•
•
•
•
3. Inspect:
• Air filter element
Damage → Replace.
4. Apply:
• Foam-air-filter oil or equivalent oil
to the element
Squeeze out the excess oil. Element
should be wet but not dripping.
CLEANING THE AIR FILTER
ELEMENT
5. Install:
• Air filter guide "1"
Proper air filter maintenance is the
biggest key to preventing premature
engine wear and damage.
Align the projection "a" on filter guide
with the hole "b" in air filter element.
Never run the engine without the
air filter element in place; this
would allow dirt and dust to enter
the engine and cause rapid wear
and possible engine damage.
3-8
ENGINE
6. Apply:
• Lithium soap base grease
On the matching surface "a" on air
filter element.
7.
•
•
•
Install:
Air filter element "1"
Washer
Fitting bolt
Fitting bolt:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Align the projection "a" on filter guide
with the hole "b" in air filter case.
CHECKING THE ENGINE OIL
LEVEL
1. Start the engine, warm it up for
several minutes, and then turn off
the engine and wait for five minutes.
2. Place the machine on a level
place and hold it up on upright position by placing the suitable
stand under the engine.
3. Inspect:
• Oil level
The engine oil level should be between the minimum level mark "a"
and maximum level mark "b".
Below the minimum level mark →
Add the recommended engine oil
to the proper level.
• Engine oil also lubricates the
clutch and the wrong oil types or
additives could cause clutch
slippage. Therefore, do not add
any chemical additives or use engine oils with a grade of CD or
higher and do not use oils labeled "ENERGY CONSERVING
II".
• Do not allow foreign materials to
enter the crankcase.
4.
•
•
•
•
•
•
•
Remove:
Lower engine guard "1"
Bolt (oil tank) "2"
Washer "3"
Oil filler cap "4"
Oil tank drain bolt "5"
Crankcase oil drain bolt "6"
Oil filter element drain bolt "7"
Drain the crankcase and oil tank
of its oil.
5.
•
•
•
•
Remove:
Oil hose clamp "1"
Bolt (oil hose)
Oil hose "2"
Oil strainer "3"
Recommended brand:
YAMALUBE
Recommended engine
oil type
SAE10W-30, SAE 10W40, SAE 10W-50, SAE
15W-40, SAE 20W-40 or
SAE 20W-50
Recommended engine
oilgrade
API service SG type or
higher, JASO standard
MA
4. Install:
• Oil tank cap
5. Start the engine and let it warm up
for several minutes.
6. Turn off the engine and inspect
the oil level once again.
Wait a few minutes until the oil settles
before inspecting the oil level.
CHANGING THE ENGINE OIL
1. Start the engine and warm it up
for several minutes, and then turn
off the engine and wait for five
minute.
2. Place the machine on a level
place and hold it on upright position by placing the suitable stand
under the engine.
3. Place a suitable container under
the engine.
3-9
6. Inspect:
• Oil strainer
Clogged → Blow.
7. If the oil filter is to be replaced during this oil change, remove the following parts and reinstall them.
ENGINE
• Oil tank drain bolt
Replacement steps:
a. Remove the oil filter element cover "1" and oil filter element "2".
b. Check the O-rings "3", if cracked
or damaged, replace them with a
new one.
c. Install the oil filter element and oil
filter element cover.
Oil filter element cover:
10 Nm (1.0 m•kg, 7.2
ft•lb)
8. Install:
• O-ring "1"
• Oil strainer "2"
Oil tank drain bolt:
18 Nm (1.8 m•kg, 13
ft•lb)
• Lower engine guard
10. Fill:
• Engine oil
Oil quantity:
Periodic oil change:
0.95 L (0.84 Imp qt,
1.00 US qt)
With oil filter replacement:
1.05 L (0.92 Imp qt,
1.11 US qt)
Total amount:
1.20 L (1.06 Imp qt,
1.27 US qt)
• Oil hose
• Bolt (oil hose)
• Oil hose clamp
Oil hose clamp:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Oil pressure check bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Lower engine guard:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Oil strainer:
9 Nm (0.9 m•kg, 6.5
ft•lb)
Bolt (oil hose):
8 Nm (0.8 m•kg, 5.8
ft•lb)
e. Tighten the oil pressure check
bolt.
11. Check:
• Oil leakage
12. Install:
• Oil filler cap
• Washer (oil tank)
• Bolt (oil tank)
ADJUSTING THE PILOT SCREW
1. Adjust:
• Pilot screw "1"
Adjustment steps:
To optimize the fuel flow at a smaller
throttle opening, each machine's pilot
screw has been individually set at the
factory. Before adjusting the pilot
screw, turn it in fully and count the
number of turns. Record this number
as the factory-set number of turns
out.
a. Turn in the pilot screw until it is
lightly seated.
b. Turn out the pilot screw by the
factory-set number of turns.
Pilot screw (example):
1-3/4 turns out
Bolt (oil tank):
4 Nm (0.4 m•kg, 2.9
ft•lb)
13. Check:
• Engine oil level
CHECKING THE OIL PRESSURE
1. Check:
• Oil pressure
9. Install:
• Copper washer
• Oil filter element drain bolt
Oil filter element drain
bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Crankcase oil drain bolt
Crankcase oil drain bolt:
20 Nm (2.0 m•kg, 14
ft•lb)
Checking steps:
a. Slightly loosen the oil pressure
check bolt "1".
b. Start the engine and keep it idling
until oil starts to seep from the oil
pressure check bolt. If no oil
comes out after one minute, turn
the engine off so it will not seize.
c. Check oil passages and oil pump
for damage or leakage.
d. Start the engine after solving the
problem(s) and recheck the oil
pressure.
3-10
ADJUSTING THE ENGINE IDLING
SPEED
1. Start the engine and thoroughly
warm it up.
2. Adjust:
• Engine idling speed
Adjustment steps:
a. Adjust the pilot screw.
Refer to "ADJUSTING THE PILOT SCREW" section.
ENGINE
b. Turn the throttle stop screw "1"
until the specified engine idling
speed.
Using a digital engine tachometer for
idle speed adjustment, detect the engine idling speed by bringing the
sensing element "c" of the engine tachometer close to the ignition coil "2".
To increase idle speed→Turn the
throttle stop screw "1" in "a".
To decrease idle speed→Turn the
throttle stop screw "1" out "b".
Engine idling speed:
1,900–2,100 r/min
1. Remove:
• Seat
• Fuel tank
Refer to "SEAT, FUEL TANK
AND SIDE COVERS" section in
the CHAPTER 4.
2. Remove:
• Spark plug
• Cylinder head cover
Refer to "CAMSHAFTS" section
in the CHAPTER 4.
3. Remove:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw
"2"
• O-ring
c. Measure the valve clearance "e"
using a feeler gauge "1".
Record the measured reading if the
clearance is incorrect.
4. Check:
• Valve clearance
Out of specification → Adjust.
Valve clearance (cold):
Intake valve:
0.12–0.17 mm
(0.0047–0.0067 in)
Exhaust valve:
0.17–0.22 mm
(0.0067–0.0087 in)
ADJUSTING THE VALVE
CLEARANCE
• This section is intended for those
who have basic knowledge and skill
concerning the servicing of Yamaha motorcycles (e.g., Yamaha dealers, service engineers, etc.) Those
who have little knowledge and skill
concerning servicing are requested
not to undertake inspection, adjustment, disassembly, or reassembly
only by reference to this manual. It
may lead to servicing trouble and
mechanical damage.
• The valve clearance should be adjusted when the engine is cool to
the touch.
• The piston must be at Top Dead
Center (T.D.C.) on compression
stroke to check or adjust the valve
clearance.
Checking steps:
a. Turn the crankshaft counterclockwise with a wrench.
b. Align the T.D.C. mark "a" on the
rotor with the align mark "b" on the
crankcase cover when piston is at
T.D.C. on compression stroke.
In order to be sure that the piston is at
Top Dead Center, the punch mark "c"
on the exhaust camshaft and the
punch mark "d" on the intake camshaft must align with the cylinder
head surface, as shown in the illustration.
3-11
5. Adjust:
• Valve clearance
Adjustment steps:
a. Remove the camshaft (intake and
exhaust).
Refer to "CAMSHAFTS" section
in the CHAPTER 4.
b. Remove the valve lifters "1" and
the pads "2".
• Place a rag in the timing chain
space to prevent pads from falling
into the crankcase.
• Identity each valve lifter and pad
position very carefully so that they
can be reinstalled in their original
place.
ENGINE
f.
c. Select the proper pad using the
pad selecting table.
Pad range
No.
120–N
o. 240
Pad Availability: 25 increments
Install the new pads "3" and the
valve lifters "4".
• Apply the engine oil on the valve lifters.
• Apply the molybdenum disulfide oil
on the valve stem ends.
• Valve lifter must turn smoothly
when rotated with a finger.
• Be careful to reinstall valve lifters
and pads in their original place.
1.20
Pads are availmm–2. able in 0.05 mm
40 mm
increments
The thickness "a" of each pad is indicated in hundredths of millimeters on
the pad upper surface.
g. Install the camshafts (exhaust
and intake).
Refer to "CAMSHAFTS" section
in the CHAPTER 4.
d. Round off the last digit of the installed pad number to the nearest
increment.
Last digit of pad
number
Rounded valve
0, 1 or 2
0
4, 5 or 6
5
8 or 9
10
EXAMPLE:
Installed pad number = 148
Rounded off value = 150
Pads can only be selected in 0.05
mm increments.
e. Locate the rounded-off value and
the measured valve clearance in
the chart "PAD SELECTION TABLE". The field where these two
coordinates intersect shows the
new pad number to use.
Use the new pad number only as a
guide when verifying the valve clearance adjustment.
3-12
ENGINE
INTAKE
MEASURED
CLEARANCE
0.00 - 0.01
0.02 - 0.06
0.07 - 0.11
0.12 - 0.17
0.18 - 0.22
0.23 - 0.27
0.28 - 0.32
0.33 - 0.37
0.38 - 0.42
0.43 - 0.47
0.48 - 0.52
0.53 - 0.57
0.58 - 0.62
0.63 - 0.67
0.68 - 0.72
0.73 - 0.77
0.78 - 0.82
0.83 - 0.87
0.88 - 0.92
0.93 - 0.97
0.98 - 1.02
1.03 - 1.07
1.08 - 1.12
1.13 - 1.17
1.18 - 1.22
1.23 - 1.27
1.28 - 1.32
1.33 - 1.37
120 125 130 135
120
120 125
120 125 130
140
125
130
135
145
130
135
140
150
135
140
145
155
140
145
150
125
130
135
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
120 125 130 135
120
120 125
120 125 130
140
125
130
135
145
130
135
140
150
135
140
145
155
140
145
150
125
130
135
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
130
135
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
135
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
INSTALLED PAD NUMBER
160 165 170 175 180 185 190 195 200 205 210 215 220 225
145 150 155 160 165 170 175 180 185 190 195 200 205 210
150 155 160 165 170 175 180 185 190 195 200 205 210 215
155 160 165 170 175 180 185 190 195 200 205 210 215 220
STANDARD CLEARANCE
165 170 175 180 185 190 195 200 205 210 215 220 225 230
170 175 180 185 190 195 200 205 210 215 220 225 230 235
175 180 185 190 195 200 205 210 215 220 225 230 235 240
180 185 190 195 200 205 210 215 220 225 230 235 240
185 190 195 200 205 210 215 220 225 230 235 240
190 195 200 205 210 215 220 225 230 235 240
195 200 205 210 215 220 225 230 235 240
200 205 210 215 220 225 230 235 240
205 210 215 220 225 230 235 240
210 215 220 225 230 235 240
215 220 225 230 235 240
220 225 230 235 240
225 230 235 240
VALVE CLEARANCE (cold):
230 235 240
0.12 - 0.17 mm
235 240
240
Example: Installed is 175
230
215
220
225
235
220
225
230
240
225
230
235
235 240
240
Measured clearance is 0.23 mm
Replace 175 pad with 185 pad
Pad number: (example)
Pad No. 175 = 1.75 mm
Pad No. 185 = 1.85 mm
EXHAUST
MEASURED
CLEARANCE
0.00 - 0.04
0.05 - 0.09
0.10 - 0.16
0.17 - 0.22
0.23 - 0.25
0.26 - 0.30
0.31 - 0.35
0.36 - 0.40
0.41 - 0.45
0.46 - 0.50
0.51 - 0.55
0.56 - 0.60
0.61 - 0.65
0.66 - 0.70
0.71 - 0.75
0.76 - 0.80
0.81 - 0.85
0.86 - 0.90
0.91 - 0.95
0.96 - 1.00
1.01 - 1.05
1.06 - 1.10
1.11 - 1.15
1.16 - 1.20
1.21 - 1.25
1.26 - 1.30
1.31 - 1.35
1.36 - 1.40
130
135
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
135
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
140
145
150
155
160
165
170
175
180
185
190
195
200
205
210
215
220
225
230
235
240
INSTALLED PAD NUMBER
160 165 170 175 180 185 190 195 200 205 210 215 220 225
145 150 155 160 165 170 175 180 185 190 195 200 205 210
150 155 160 165 170 175 180 185 190 195 200 205 210 215
155 160 165 170 175 180 185 190 195 200 205 210 215 220
STANDARD CLEARANCE
165 170 175 180 185 190 195 200 205 210 215 220 225 230
170 175 180 185 190 195 200 205 210 215 220 225 230 235
175 180 185 190 195 200 205 210 215 220 225 230 235 240
180 185 190 195 200 205 210 215 220 225 230 235 240
185 190 195 200 205 210 215 220 225 230 235 240
190 195 200 205 210 215 220 225 230 235 240
195 200 205 210 215 220 225 230 235 240
200 205 210 215 220 225 230 235 240
205 210 215 220 225 230 235 240
210 215 220 225 230 235 240
215 220 225 230 235 240
220 225 230 235 240
225 230 235 240
VALVE CLEARANCE (cold):
230 235 240
235 240
0.17 - 0.22 mm
240
Example: Installed is 175
230
215
220
225
235
220
225
230
235 240
240
Measured clearance is 0.27 mm
Replace 175 pad with 185 pad
Pad number: (example)
Pad No. 175 = 1.75 mm
Pad No. 185 = 1.85 mm
3-13
240
225
230
235
CHASSIS
CHASSIS
BLEEDING THE HYDRAULIC
BRAKE SYSTEM
Bleed the brake system if:
• The system has been disassembled.
• A brake hose has been loosened
or removed.
• The brake fluid is very low.
• The brake operation is faulty.
A dangerous loss of braking performance may occur if the brake
system is not properly bled.
1.
•
•
•
•
2.
•
Remove:
Brake master cylinder cap
Diaphragm
Reservoir float (front brake)
Protector (rear brake)
Bleed:
Brake fluid
Air bleeding steps:
a. Add proper brake fluid to the reservoir.
b. Install the diaphragm. Be careful
not to spill any fluid or allow the
reservoir to overflow.
c. Connect the clear plastic tube "2"
tightly to the caliper bleed screw
"1".
h. Tighten the bleed screw when the
lever or pedal limit has been
reached; then release the lever or
pedal.
b. Turn the adjusting bolt "2" until the
lever position "a" is within specified position.
Bleed screw:
6 Nm (0.6 m•kg, 4.3
ft•lb)
i.
Repeat steps (e) to (h) until of the
air bubbles have been removed
from the system.
c. Tighten the locknut.
If bleeding is difficult, it may be necessary to let the brake fluid system
stabilize for a few hours. Repeat the
bleeding procedure when the tiny
bubbles in the system have disappeared.
j.
Add brake fluid to the level line on
the reservoir.
Check the operation of the brake
after bleeding the brake system.
3. Install:
• Protector (rear brake)
• Reservoir float (front brake)
• Diaphragm
• Brake master cylinder cap
ADJUSTING THE FRONT BRAKE
1. Check:
• Brake lever position "a"
Locknut:
5 Nm (0.5 m •kg, 3.6
ft•lb)
Be sure to tighten the locknut, as it
will cause poor brake performance.
4. Install:
• Brake lever cover
ADJUSTING THE REAR BRAKE
1. Check:
• Brake pedal height "a"
Out of specification → Adjust.
Brake pedal height "a":
Zero mm (Zero in)
Brake lever position "a":
A. Front
B. Rear
d. Place the other end of the tube
into a container.
e. Slowly apply the brake lever or
pedal several times.
f. Pull the lever in or push down on
the pedal. Hold the lever or pedal
in position.
g. Loosen the bleed screw and allow
the lever or pedal to travel towards its limit.
Standard position
Extent of adjustment
95 mm (3.74 in)
86–105 mm
(3.39–4.13 in)
2. Adjust:
• Brake pedal height
Pedal height adjustment steps:
a. Loosen the locknut "1".
b. Turn the adjusting nut "2" until the
pedal height "a" is within specified
height.
c. Tighten the locknut.
2.
•
3.
•
Remove:
Brake lever cover
Adjust:
Brake lever position
Brake lever position adjustment
steps:
a. Loosen the locknut "1".
3-14
• Adjust the pedal height between
the maximum "A" and the minimum "B" as shown. (In this adjustment, the bolt "3" end "b"
should protrude out of the
threaded portion "4" but not be
less than 2 mm (0.08 in) "c" away
from the brake pedal "5").
• After the pedal height adjustment, make sure that the rear
brake does not drag.
CHASSIS
d. Remove the pad pin and brake
pads "4".
j.
e. Connect the transparent hose "5"
to the bleed screw "6" and place
the suitable container under its
end.
CHECKING AND REPLACING THE
FRONT BRAKE PADS
1. Inspect:
• Brake pad thickness "a"
Out of specification → Replace as
a set.
Brake pad thickness:
4.4 mm (0.17 in)
<Limit>: 1.0 mm (0.04
in)
f.
Loosen the bleed screw and push
the brake caliper piston in.
Do not reuse the drained brake fluid.
g. Tighten the bleed screw.
Bleed screw:
6 Nm (0.6 m•kg, 4.3
ft•lb)
h. Install the brake pads "7" and pad
pin.
2. Replace:
• Brake pad
Brake pad replacement steps:
a. Remove the pad pin plug "1".
b. Loosen the pad pin "2".
c. Remove the brake caliper "3"
from the front fork.
• Install the brake pads with their projections "a" into the brake caliper recesses "b".
• Temporarily tighten the pad pin at
this point.
i.
Install the brake caliper "8" and
tighten the pad pin "9".
Bolt (brake caliper):
28 Nm (2.8 m•kg, 20
ft•lb)
Pad pin:
18 Nm (1.8 m•kg, 13
ft•lb)
3-15
Install the pad pin plug "10".
Pad pin plug:
3 Nm (0.3 m•kg, 2.2
ft•lb)
3. Inspect:
• Brake fluid level
Refer to "CHECKING THE
BRAKE FLUID LEVEL" section.
4. Check:
• Brake lever operation
A softy or spongy feeling → Bleed
brake system.
Refer to "BLEEDING THE HYDRAULIC BRAKE SYSTEM" section.
CHECKING AND REPLACING THE
REAR BRAKE PADS
1. Inspect:
• Brake pad thickness "a"
Out of specification → Replace as
a set.
Brake pad thickness:
6.4 mm (0.25 in)
<Limit>: 1.0 mm (0.04
in)
CHASSIS
2. Replace:
• Brake pad
h. Install the brake pad "10" and pad
pin "11".
Brake pad replacement steps:
a. Remove the protector "1" and pad
pin plug "2".
• Install the brake pads with their projections "a" into the brake caliper recesses "b".
• Temporarily tighten the pad pin at
this point.
b. Loosen the pad pin "3".
c. Remove the rear wheel "4" and
brake caliper "5".
Refer to "FRONT WHEEL AND
REAR WHEEL" section in the
CHAPTER 5.
i.
j.
Install the brake caliper "12" and
rear wheel "13".
Refer to "FRONT WHEEL AND
REAR WHEEL" section in the
CHAPTER 5.
Tighten the pad pin "14".
Pad pin:
18 Nm (1.8 m•kg, 13
ft•lb)
d. Remove the pad pin "6" and brake
pads "7".
k. Install the pad pin plug "15" and
protector "16".
e. Connect the transparent hose "8"
to the bleed screw "9" and place
the suitable container under its
end.
f.
Pad pin plug:
3 Nm (0.3 m•kg, 2.2
ft•lb)
Bolt (protector):
7 Nm (0.7 m•kg, 5.1
ft•lb)
Loosen the bleed screw and push
the brake caliper piston in.
Do not reuse the drained brake fluid.
g. Tighten the bleed screw.
4. Check:
• Brake pedal operation
A softy or spongy feeling → Bleed
brake system.
Refer to "BLEEDING THE HYDRAULIC BRAKE SYSTEM" section.
CHECKING THE REAR BRAKE
PAD INSULATOR
1. Remove:
• Brake pad
Refer to "CHECKING AND REPLACING THE REAR BRAKE
PADS" section.
2. Inspect:
• Rear brake pad insulator "1"
Damage → Replace.
CHECKING THE BRAKE FLUID
LEVEL
1. Place the brake master cylinder
so that its top is in a horizontal position.
2. Inspect:
• Brake fluid level
Fluid at lower level → Fill up.
Recommended brake fluid:
DOT #4
• Use only designated quality
brake fluid to avoid poor brake
performance.
• Refill with same type and brand
of brake fluid; mixing fluids
could result in poor brake performance.
• Be sure that water or other contaminants do not enter master
cylinder when refilling.
• Clean up spilled fluid immediately to avoid erosion of painted
surfaces or plastic parts.
3. Inspect:
• Brake fluid level
Refer to "CHECKING THE
BRAKE FLUID LEVEL" section.
Bleed screw:
6 Nm (0.6 m•kg, 4.3
ft•lb)
a. Lower level
A. Front
B. Rear
3-16
CHASSIS
CHECKING THE SPROCKET
1. Inspect:
• Sprocket teeth "a"
Excessive wear → Replace.
Replace the drive sprocket, rear
wheel sprocket and drive chain as a
set.
3. Clean:
• Drive chain
Place it in kerosene, and brush off
as much dirt as possible. Then remove the drive chain from the kerosene and dry the drive chain.
ADJUSTING THE DRIVE CHAIN
SLACK
1. Elevate the rear wheel by placing
the suitable stand under the engine.
2. Check:
• Drive chain slack "a"
Above the seal guard installation
bolt.
Out of specification → Adjust.
Drive chain slack:
50–60 mm (2.0–2.4 in)
CHECKING THE DRIVE CHAIN
1. Measure:
• Drive chain length (15 links) "a"
Out of specification → Replace.
4. Check:
• Drive chain stiffness "a"
Clean and oil the drive chain and
hold as illustrated.
Stiff → Replace the drive chain.
Drive chain length (15
links):
<Limit>: 242.9 mm
(9.563 in)
• While measuring the drive chain
length, push down on the drive
chain to increase its tension.
• Measure the length between drive
chain roller "1" and "16" as shown.
• Perform this measurement at two or
three different places.
2.
•
•
•
Remove:
Master link clip
Joint "1"
Drive chain "2"
5.
•
•
•
Install:
Drive chain "1"
Joint "2"
Master link clip "3"
Be sure to install the master link
clip to the direction as shown.
a. Turning direction
6. Lubricate:
• Drive chain
Drive chain lubricant:
SAE 10W-40 motor oil
or suitable chain lubricants
3-17
Before checking and/or adjusting, rotate the rear wheel through several
revolutions and check the slack several times to find the tightest point.
Check and/or adjust the drive chain
slack with the rear wheel in this "tight
chain" position.
3. Adjust:
• Drive chain slack
Drive chain slack adjustment
steps:
a. Loosen the axle nut "1" and locknuts "2".
b. Adjust the drive chain slack by
turning the adjusters "3".
To tighten→Turn the adjuster "3"
counterclockwise.
To loosen→Turn the adjuster "3"
clockwise and push wheel forward.
c. Turn each adjuster exactly the
same amount to maintain correct
axle alignment. (There are marks
"a" on each side of the drive chain
puller alignment.) NOTICE: Improper drive chain slack will
overload the engine aswell as
other vital parts of the motorcycle and can lead to chain slippage or breakage. To prevent
this from occurring, keep the
drive chain slack within the
specified limits.
CHASSIS
CLEANING THE FRONT FORK OIL
SEAL AND DUST SEAL
1. Remove:
• Protector
• Dust seal "1"
A. Right
B. Left
Use a thin screw driver, and be careful not to damage the inner fork tube
and dust seal.
Turn the adjuster so that the drive
chain is in line with the sprocket, as
viewed from the rear.
e. Tighten the locknuts.
Locknut:
21 Nm (2.1 m•kg, 15
ft•lb)
Maximum
2. Clean:
• Dust seal "a"
• Oil seal "b"
20 clicks out
(from maximum
position)
• STANDARD POSITION:
This is the position which is back
by the specific number of clicks
from the fully turned-in position.
RELIEVING THE FRONT FORK
INTERNAL PRESSURE
If the front fork initial movement feels
stiff during a run, relieve the front fork
internal pressure.
The protector guide reaches the limit
of its use when it is worn down to the
same height "a" as of the outer tube
circumference.
Fully turned in
position
Minimum
• Clean the dust seal and oil seal after every run.
• Apply the lithium soap base grease
on the inner tube.
CHECKING THE FRONT FORK
1. Inspect:
• Front fork smooth action
Operate the front brake and
stroke the front fork.
Unsmooth action/oil leakage →
Repair or replace.
CHECKING THE FRONT FORK
PROTECTOR GUIDE
1. Inspect:
• Protector guide "1"
Out of specification → Replacet.
Stiffer "a" → Increase the rebound damping force. (Turn
the adjuster "1" in.)
Softer "b" → Decrease the rebound damping force. (Turn
the adjuster "1" out.)
Extent of adjustment:
d. Tighten the axle nut while pushing
down the drive chain.
Axle nut:
135 Nm (13.5 m•kg, 98
ft•lb)
ADJUSTING THE FRONT FORK
REBOUND DAMPING FORCE
1. Adjust:
• Rebound damping force
By turning the adjuster "1".
1. Elevate the front wheel by placing
a suitable stand under the engine.
2. Remove the air bleed screw "1"
and release the internal pressure
from the front fork.
3. Install:
• Air bleed screw
Air bleed screw:
1 Nm (0.1 m•kg, 0.7
ft•lb)
3-18
Standard position:
10 clicks out
* 9 clicks out
* Except for USA and CDN
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
Always adjust each front fork to
the same setting. Uneven adjustment can cause poor handling and
loss of stability.
CHASSIS
ADJUSTING THE FRONT FORK
COMPRESSION DAMPING FORCE
2. Adjust:
• Compression damping force
By turning the adjuster "1".
Stiffer "a" → Increase the compression damping force. (Turn
the adjuster "1" in.)
Softer "b" → Decrease the compression damping force. (Turn
the adjuster "1" out.)
Extent of adjustment:
Maximum
Fully turned in
position
Minimum
20 clicks out
(from maximum
position)
ADJUSTING THE REAR SHOCK
ABSORBER SPRING PRELOAD
1. Elevate the rear wheel by placing
the suitable stand under the engine.
2. Remove:
• Rear frame
3. Measure:
• Spring fitting length
Standard fitting length:
I.D. MARK/Q'TY
Yellow/1
Length
250 mm
(9.84 in)
• STANDARD POSITION:
This is the position which is back
by the specific number of clicks
from the fully turned-in position.
CHECKING THE REAR SHOCK
ABSORBER
1. Inspect:
• Swingarm smooth action
Abnormal noise/unsmooth action
→ Grease the pivoting points or
repair the pivoting points.
Damage/oil leakage → Replace.
Minimum
Position in
which the
spring is turned
in 20 mm (0.79
in) from its free
length.
Position in
which the
spring is turned
in 1.5 mm (0.06
in) from its free
length.
• Be sure to remove all dirt and mud
from around the locknut and adjuster before adjustment.
• The length of the spring (installed)
changes 1.5 mm (0.06 in) per turn
of the adjuster.
e. Tighten the locknut.
Locknut:
30 Nm (3.0 m•kg, 22
ft•lb)
* Except for USA and CDN
Always adjust each front fork to
the same setting. Uneven adjustment can cause poor handling and
loss of stability.
Maximum
Never attempt to turn the adjuster
beyond the maximum or minimum
setting.
Standard position:
8 clicks out
* 6 clicks out
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
Extent of adjustment:
5. Install:
• Rear frame (upper)
The I.D. mark "a" is marked at the end
of the spring.
4. Adjust:
• Spring preload
Adjustment steps:
a. Loosen the locknut "1".
b. Loosen the adjuster "2" until there
is some clearance between the
spring and adjuster.
c. Measure the spring free length
"a".
d. Turn the adjuster "2".
Stiffer → Increase the spring preload. (Turn the adjuster "2" in.)
Softer → Decrease the spring preload. (Turn the adjuster "2"
out.)
3-19
Rear frame (upper):
32 Nm (3.2 m•kg, 23
ft•lb)
• Rear frame (lower)
Rear frame (lower):
32 Nm (3.2 m•kg, 23
ft•lb)
ADJUSTING THE REAR SHOCK
ABSORBER REBOUND DAMPING
FORCE
1. Adjust:
• Rebound damping force
By turning the adjuster "1".
Stiffer "a" → Increase the rebound damping force. (Turn
the adjuster "1" in.)
Softer "b" → Decrease the rebound damping force. (Turn
the adjuster "1" out.)
CHASSIS
Extent of adjustment:
Maximum
Fully turned in
position
Minimum
20 clicks out
(from maximum
position)
• STANDARD POSITION:
This is the position which is back
by the specific number of clicks
from the fully turned-in position.
(Which align the punch mark "a"
on the adjuster with the punch
mark "b" on the bracket.)
Standard position:
About 10 clicks out
* About 6 clicks out
* Except for USA and CDN
• STANDARD POSITION:
This is the position which is back
by the specific number of clicks
from the fully turned-in position.
(Which align the punch mark "a"
on the adjuster with the punch
mark "b" on the high compression
damping adjuster.)
Standard position:
About 9 clicks out
* About 11 clicks out
• STANDARD POSITION:
This is the position which is back
by the specific number of turns
from the fully turned-in position.
(Which align the punch mark "a"
on the adjuster with the punch
mark "b" on the adjuster body.)
Standard position:
About 1-3/4 turns out
*About 1-1/2 turns out
* Except for USA and CDN
* Except for USA and CDN
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
Do not force the adjuster past the
minimum or maximum extent of
adjustment. The adjuster may be
damaged.
ADJUSTING THE REAR SHOCK
ABSORBER HIGH COMPRESSION
DAMPING FORCE
1. Adjust:
• High compression damping force
By turning the adjuster "1".
ADJUSTING THE REAR SHOCK
ABSORBER LOW COMPRESSION
DAMPING FORCE
1. Adjust:
• Low compression damping force
By turning the adjuster "1".
Stiffer "a" → Increase the low
compression damping force.
(Turn the adjuster "1" in.)
Softer "b" → Decrease the low
compression damping force.
(Turn the adjuster "1" out.)
Stiffer "a" → Increase the high
compression damping force.
(Turn the adjuster "1" in.)
Softer "b" → Decrease the high
compression damping force.
(Turn the adjuster "1" out.)
Extent of adjustment:
Maximum
Minimum
Fully turned in
position
2 turns out
(from maximum
position)
Extent of adjustment:
Maximum
Fully turned in
position
Minimum
20 clicks out
(from maximum
position)
3-20
CHECKING THE TIRE PRESSURE
1. Measure:
• Tire pressure
Out of specification → Adjust.
Standard tire pressure:
100 kPa (1.0 kgf/cm2,
15 psi)
• Check the tire while it is cold.
• Loose bead stoppers allow the tire
to slip off its position on the rim
when the tire pressure is low.
• A tilted tire valve stem indicates that
the tire slips off its position on the
rim.
• If the tire valve stem is found tilted,
the tire is considered to be slipping
off its position. Correct the tire position.
CHASSIS
CHECKING AND TIGHTENING THE
SPOKES
The following procedure applies to all
of the spokes.
1. Check:
• Spokes
Bend/damage → Replace.
Loose spoke → Retighten.
Tap the spokes with a screwdriver.
A tight spoke will emit a clear, ringing
tone; a loose spoke will sound flat.
2. Tighten:
• Spokes
(with a spoke nipple wrench "1")
2. Inspect:
• Bearing free play
Exist play → Replace.
CHECKING AND ADJUSTING THE
STEERING HEAD
1. Place a stand under the engine to
raise the front wheel off the
ground. WARNING! Securely
support the vehicle so that
there is no danger of it falling
over.
2. Check:
• Steering stem
Grasp the bottom of the forks and
gently rock the fork assembly
back and forth.
Free play → Adjust steering head.
d. Tighten the steering ring nut "3"
using steering nut wrench "4".
• Apply the lithium soap base grease
on the thread of the steering stem.
• Set the torque wrench to the steering nut wrench so that they form a
right angle.
Steering nut wrench:
YU-33975/90890-01403
3. Check:
• Steering smooth action
Turn the handlebar lock to lock.
Unsmooth action → Adjust steering ring nut.
e. Loosen the steering ring nut one
turn.
f. Retighten the steering ring nut using the steering nut wrench.
Spokes:
3 Nm (0.3 m•kg, 2.2
ft•lb)
CHECKING THE WHEELS
1. Inspect:
• Wheel runout
Elevate the wheel and turn it.
Abnormal runout → Replace.
Steering nut wrench:
YU-33975/90890-01403
Steering ring nut (initial
tightening):
38 Nm (3.8 m•kg, 27
ft•lb)
Be sure to retighten these spokes before and after break-in.
Spoke nipple wrench:
YM-01521/90980-01521
c. Loosen the steering ring nut "1"
using the steering nut wrench "2".
Avoid over-tightening.
4. Adjust:
• Steering ring nut
Steering ring nut adjustment
steps:
a. Remove the number plate.
b. Remove the handlebar and upper
bracket.
3-21
Steering ring nut (final
tightening):
7 Nm (0.7 m•kg, 5.1
ft•lb)
g. Check the steering stem by turning it lock to lock. If there is any
binding, remove the steering stem
assembly and inspect the steering bearings.
CHASSIS
h. Install the washer "5", upper
bracket "6", steering stem nut "7",
handlebar "8", handlebar upper
holder "9" and number plate "10".
• Apply the lithium soap base grease
on the contact surface of the steering stem nut when installing.
• The handlebar upper holder should
be installed with the punched mark
"a" forward.
• Install the handlebar so that the
marks "b" are in place on both
sides.
• Install the handlebar so that the projection "c" of the handlebar upper
holder is positioned at the mark on
the handlebar as shown.
• Insert the end of the fuel breather
hose "11" into the hole in the steering stem.
First tighten the bolts on the front
side of the handlebar upper holder,
and then tighten the bolts on the
rear side.
Steering stem nut:
145 Nm (14.5 m•kg, 105
ft•lb)
Handlebar upper holder:
28 Nm (2.8 m•kg, 20
ft•lb)
Pinch bolt (upper bracket):
21 Nm (2.1 m•kg, 15
ft•lb)
Number plate:
7 Nm (0.7 m•kg, 5.1
ft•lb)
3-22
CHASSIS
LUBRICATION
To ensure smooth operation of all
components, lubricate your machine
during setup, after break-in, and after
every race.
1. All control cable
2. Clutch lever pivot
3. Shift pedal pivot
4. Footrest pivot
5. Throttle-to-handlebar contact
6. Drive chain
7. Tube guide cable winding portion
8. Throttle cable end
9. Clutch cable end
10. Hot starter cable end
A.
B.
C.
Use Yamaha cable lube or
equivalent on these areas.
Use SAE 10W-40 motor oil or
suitable chain lubricants.
Lubricate the following areas
with high quality, lightweight lithium-soap base grease.
Wipe off any excess grease, and
avoid getting grease on the brake
discs.
3-23
ELECTRICAL
ELECTRICAL
CHECKING THE SPARK PLUG
1. Remove:
• Spark plug
2. Inspect:
• Electrode "1"
Wear/damage → Replace.
• Insulator color "2"
Normal condition is a medium to
light tan color.
Distinctly different color → Check
the engine condition.
When the engine runs for many hours
at low speeds, the spark plug insulator will become sooty, even if the engine and carburetor are in good
operating condition.
3. Measure:
• Plug gap "a"
Use a wire gauge or thickness
gauge.
Out of specification → Regap.
Spark plug gap:
0.7–0.8 mm
(0.028–0.031 in)
4. Clean the plug with a spark plug
cleaner if necessary.
5. Tighten:
• Spark plug
CHECKING THE IGNITION TIMING
1. Remove:
• Timing mark accessing screw "1"
2. Attach:
• Timing light
• Digital tachometer
To the ignition coil lead (orange
lead"1").
Timing light:
YM-33277-A/9089003141
3. Adjust:
• Engine idling speed
Refer to "ADJUSTING THE ENGINE IDLING SPEED" section.
4. Check:
• Ignition timing
Visually check the stationary
pointer "a" is within the firing
range "b" on the rotor.
Incorrect firing range → Check rotor and pickup assembly.
Spark plug:
13 Nm (1.3 m•kg, 9.4
ft•lb)
• Before installing a spark plug, clean
the gasket surface and plug surface.
• Finger-tighten "a" the spark plug
before torquing to specification "b".
5. Install:
• Timing mark accessing screw
3-24
SEAT, FUEL TANK AND SIDE COVERS
ENGINE
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are requested not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.
SEAT, FUEL TANK AND SIDE COVERS
REMOVING THE SEAT, FUEL TANK AND SIDE COVERS
4
Order
Part name
Q'ty
Remarks
Turn the fuel cock to "OFF".
Disconnect the fuel hose.
1
Seat
1
2
Air scoop (left and right)
2
3
Bolt (fuel tank)
1
4
Fitting band
1
5
Fuel tank
1
6
Left side cover
1
Refer to removal section.
7
Right side cover
1
Refer to removal section.
8
Number plate
1
Refer to removal section.
4-1
SEAT, FUEL TANK AND SIDE COVERS
REMOVING THE SIDE COVER
1. Remove:
• Bolt (side cover)
• Left side cover "1"
• Right side cover "2"
Draw the side cover downward to remove it because its claws "a" are inserted in the air filter case.
REMOVING THE NUMBER PLATE
1. Remove:
• Bolt (number plate)
• Number plate "1"
• The projection "a" is inserted into
the band of the number plate. Pull
the band off the projection before
removal.
• Remove the hot starter cable "2"
and clutch cable "3" from the cable
guide "b" on the number plate.
• The projection "c" on the lower
bracket is inserted into the number
plate. Remove the number plate by
pulling it off the projection.
4-2
EXHAUST PIPE AND SILENCER
EXHAUST PIPE AND SILENCER
REMOVING THE EXHAUST PIPE AND SILENCER
Order
Part name
Q'ty
Remarks
A. Except for USA and CDN
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section.
Right side cover
1
Bolt (silencer clamp)
1
2
Bolt [silencer (front)]
1
3
Bolt [silencer (rear)]
1
4
Silencer
1
5
Silencer clamp
1
6
Nut (exhaust pipe)
2
7
Exhaust pipe
1
8
Gasket
2
9
Wave washer
3
4-3
Only loosening.
EXHAUST PIPE AND SILENCER
CHECKING THE SILENCER AND
EXHAUST PIPE
1. Inspect:
• Gasket "1"
Damage → Replace.
CHANGING THE SILENCER FIBER
1. Remove:
• Rivet (front) "1"
• Inner pipe "2"
Take care not to damage the rivet
fitting holes (ø4.9 mm) "a" in removal.
• Install the gasket with its meshed
area "a" toward the exhaust pipe
side.
• The gasket should be installed according to the dimension shown.
New
INSTALLING THE SILENCER AND
EXHAUST PIPE
1. Install:
• Gasket
• Exhaust pipe "1"
• Nut (exhaust pipe) "2"
Nut (exhaust pipe):
20 Nm (2.0 m•kg, 14
ft•lb)
Pull out the inner pipe while lightly
tapping the stay "b" on the silencer
using a soft hammer.
First temporarily tighten both nuts to
13 Nm (1.3 m•kg, 9.4 ft•lb). Then retighten the same nut to 20 Nm (2.0
m•kg, 14 ft•lb).
2. Replace:
• Fiber "1"
2. Install:
• Silencer clamp "1"
Silencer clamp:
14 Nm (1.4 m•kg, 10
ft•lb)
3. Install:
• Inner pipe "1"
• Rivet (front) "2"
• Apply heat resistant sealant along
the plate edge "a" on the inside of
the silencer and also along the silencer edge "b" as shown.
• Take care not to allow the fiber out
of place when installing the inner
pipe.
•
•
•
•
Gasket "2"
Silencer "3"
Washer "4"
Bolt (silencer) "5"
Bolt (silencer):
30 Nm (3.0 m•kg, 22
ft•lb)
4-4
RADIATOR
RADIATOR
REMOVING THE RADIATOR
2
T.
20 Nm (2.0 m kg, 14 ft Ib)
R.
4
12
2
5
13
9
2
10
2
2
1
1
2
6
2
2
8
3
2 7
2
11
Order
Part name
Q'ty
Remarks
Drain the coolant.
Refer to "CHANGING THE COOLANT" section in the CHAPTER 3.
Seat and fuel tank
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section.
1
Radiator guard
2
2
Radiator hose clamp
10
3
Clutch cable holder
1
4
Radiator hose 1
1
5
Left radiator
1
6
Radiator hose 4
1
7
Pipe
1
8
Radiator hose 5
1
9
Right radiator
1
10
Radiator hose 2
1
11
Radiator hose 3
1
12
Radiator breather hose
1
13
Radiator pipe 1
1
4-5
Only loosening.
RADIATOR
HANDLING NOTE
Do not remove the radiator cap
when the engine and radiator are
hot. Scalding hot fluid and steam
may be blown out under pressure,
which could cause serious injury.
When the engine has cooled, open
the radiator cap by the following
procedure:
Place a thick rag, like a towel, over
the radiator cap, slowly rotate the
cap counterclockwise to the detent. This procedure allows any residual pressure to escape. When
the hissing sound has stopped,
press down on the cap while turning counterclockwise and remove
it.
CHECKING THE RADIATOR
1. Inspect:
• Radiator core "1"
Obstruction → Blow out with compressed air through rear of the radiator.
Bent fin → Repair/replace.
INSTALLING THE RADIATOR
1. Install:
• O-ring "1"
• Radiator pipe 1 "2"
• Bolt (radiator pipe) "3"
Bolt (radiator pipe):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Apply the lithium soap base grease
on the O-ring.
2.
•
•
•
•
•
•
Install:
Radiator breather hose "1"
Radiator hose 2 "2"
Radiator hose 4 "3"
Pipe "4"
Radiator hose 5 "5"
Radiator hose 3 "6"
To right radiator "7".
6. Install:
• Radiator guard "1"
First fit the inner hook portion "a" and
then the outer one "b" onto the radiator.
3. Install:
• Right radiator "1"
• Bolt (right radiator) "2"
Bolt (right radiator):
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Radiator hose 5 "3"
Refer to "CABLE ROUTING DIAGRAM" section in the CHAPTER
2.
4. Install:
• Left radiator "1"
• Bolt (left radiator) "2"
Bolt (left radiator):
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Radiator hose 1 "3"
Radiator hose 1:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Refer to "CABLE ROUTING DIAGRAM" section in the CHAPTER
2.
5. Tighten:
• Radiator hose clamp "4"
Radiator hose clamp:
2 Nm (0.2 m•kg, 1.4
ft•lb)
4-6
CARBURETOR
CARBURETOR
REMOVING THE CARBURETOR
4 Nm (0.4 m kg, 2.9 ft lb)
2 Nm (0.2 m kg, 1.4 ft lb)
11 Nm (1.1 m kg, 8.0 ft lb)
4 Nm (0.4 m kg, 2.9 ft lb)
10 Nm (1.0 m kg, 7.2 ft lb)
3 Nm (0.3 m kg, 2.2 ft lb)
3 Nm (0.3 m kg, 2.2 ft lb)
Order
Part name
Q'ty
Remarks
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section.
Seat and fuel tank
1
Clamp
1
2
Throttle position sensor lead coupler
1
3
Throttle cable cover
1
4
Throttle cable
2
5
Clamp (air filter joint)
1
Loosen the screw (air filter joint).
6
Clamp (carburetor joint)
1
Loosen the screws (carburetor joint).
7
Hot starter plunger
1
8
Carburetor assembly
1
9
Carburetor joint
1
4-7
CARBURETOR
DISASSEMBLING THE CARBURETOR
Order
Part name
Q'ty
1
Carburetor breather hose
4
2
Valve lever housing cover
1
3
Screw (throttle shaft)
1
4
Throttle valve
1
5
Needle holder
1
6
Jet needle
1
7
Accelerator pump cover
1
8
Spring
1
9
Diaphragm (accelerator pump)
1
10
Float chamber
1
11
Leak jet
1
12
Pilot screw
1
13
Float pin
1
14
Float
1
15
Needle valve
1
16
Main jet
1
17
Needle jet
1
18
Spacer
1
4-8
Remarks
Refer to removal section.
CARBURETOR
Order
Part name
Q'ty
19
Pilot jet
1
20
Starter jet
1
21
Push rod
1
22
Throttle shaft assembly
1
23
Push rod link lever assembly
1
24
Pilot air jet
1
25
Cold starter plunger
1
4-9
Remarks
Pull the push rod.
CARBURETOR
HANDLING NOTE
Do not loosen the screw (throttle
position sensor) "1" except when
changing the throttle position sensor due to failure because it will
cause a drop in engine performance.
2.
•
•
•
•
•
•
Inspect:
Main jet "1"
Pilot jet "2"
Needle jet "3"
Starter jet "4"
Pilot air jet "5"
Leak jet "6"
Damage → Replace.
Contamination → Clean.
CHECKING THE JET NEEDLE
1. Inspect:
• Jet needle "1"
Bends/wear → Replace.
• Clip groove
Free play exists/wear → Replace.
• Clip position
Standard clip position:
No.4 Groove
• Use a petroleum based solvent for
cleaning. Blow out all passages and
jets with compressed air.
• Never use a wire.
REMOVING THE PILOT SCREW
1. Remove:
• Pilot screw "1"
To optimize the fuel flow at a small
throttle opening, each machine's pilot
screw has been individually set at the
factory. Before removing the pilot
screw, turn it in fully and count the
number of turns. Record this number
as the factory-set number of turns
out.
CHECKING THE CARBURETOR
1. Inspect:
• Carburetor body
Contamination → Clean.
• Use a petroleum based solvent for
cleaning. Blow out all passages and
jets with compressed air.
• Never use a wire.
CHECKING THE NEEDLE VALVE
1. Inspect:
• Needle valve "1"
• Valve seat "2"
Grooved wear "a" → Replace.
Dust "b" → Clean.
• Filter "c"
Clogged → Clean.
CHECKING THE THROTTLE
VALVE
1. Check:
• Free movement
Stick → Repair or replace.
Insert the throttle valve "1" into the
carburetor body, and check for free
movement.
MEASURING AND ADJUSTING
THE FLOAT HEIGHT
1. Measure:
• Float height "a"
Out of specification → Adjust.
Float height:
8.0 mm (0.31 in)
Measurement and adjustment
steps:
a. Hold the carburetor in an upside
down position.
• Slowly tilt the carburetor in the opposite direction, then take the measurement when the needle valve
aligns with the float arm.
• If the carburetor is level, the weight
of the float will push in the needle
valve, resulting in an incorrect measurement.
b. Measure the distance between
the mating surface of the float
chamber and top of the float using
a vernier calipers.
The float arm should be resting on the
needle valve, but not compressing
the needle valve.
4-10
CARBURETOR
c. If the float height is not within
specification, inspect the valve
seat and needle valve.
d. If either is worn, replace them
both.
e. If both are fine, adjust the float
height by bending the float tab "b"
on the float.
4. Install:
• Spring 2 "1"
To lever 2 "2".
2.
•
•
•
•
•
•
f.
Inspect:
Throttle shaft "1"
Spring "2"
Lever 1 "3"
Spring 1 "4"
Lever 2 "5"
Spring 2 "6"
Dirt → Clean.
Recheck the float height.
5. Install:
• Push rod link lever assembly "1"
Make sure the stopper "a" of the
spring 2 fits into the recess "b" in the
carburetor.
CHECKING THE FLOAT
1. Inspect:
• Float "1"
Damage → Replace.
ASSEMBLING THE CARBURETOR
1. Install:
• Cold starter plunger "1"
CHECKING THE STARTER
PLUNGER
1. Inspect:
• Cold starter plunger "1"
• Hot starter plunger "2"
Wear/damage → Replace.
2. Install:
• Pilot air jet "1"
6. Install:
• Washer "1"
• Circlip "2"
7. Install:
• Spring "1"
To throttle shaft "2".
Install the bigger hook "a" of the
spring fits on the stopper "b" of the
throttle shaft pulley.
CHECKING THE ACCELERATOR
PUMP
1. Inspect:
• Diaphragm (accelerator pump)
"1"
• Spring (accelerator pump) "2"
• Accelerator pump cover "3"
• O-ring "4"
• Push rod "5"
Tears (diaphragm)/damage→Replace.
Dirt → Clean.
3. Install:
• Spring 1 "1"
• Lever 1 "2"
To lever 2 "3".
Make sure the spring 1 fits on the
stopper "a" of the lever 2.
8.
•
•
•
•
4-11
Install:
Throttle shaft assembly "1"
Washer (metal) "2"
Washer (resin) "3"
Valve lever "4"
CARBURETOR
• Apply the fluorochemical grease on
the bearings.
• Fit the projection "a" on the throttle
shaft assembly into the slot "b" in
the throttle position sensor.
• Make sure the stopper "c" of the
spring fits into the recess in the carburetor.
• Turn the throttle shaft assembly left
while holding down the lever 1 "5"
and fit the throttle stop screw tip "d"
to the stopper "e" of the throttle
shaft assembly pulley.
11. Install:
• Needle valve "1"
• Float "2"
• Float pin "3"
• After installing the needle valve to
the float, install them to the carburetor.
• Check the float for smooth movement.
14. Install:
• Diaphragm (accelerator pump)
"1"
• Spring "2"
• O-ring "3"
• Accelerator pump cover "4"
• Hose holder (drain hose) "5"
• Screw (accelerator pump cover)
"6"
Install the diaphragm (accelerator
pump) with its mark "a" facing the
spring.
12. Install:
• Pilot screw "1"
• Spring "2"
• Washer "3"
• O-ring "4"
9. Install:
• Push rod "1"
While holding down the lever 1 "2", insert the push rod farthest into the carburetor.
Note the following installation
points:
a. Turn in the pilot screw until it is
lightly seated.
b. Turn out the pilot screw by the
number of turns recorded before
removing.
15. Install:
• Jet needle "1"
• Collar "2"
• Spring "3"
• Needle holder "4"
• Throttle valve plate "5"
To throttle valve "6".
Pilot screw (example):
1-3/4 turns out
16. Install:
• Throttle valve assembly "1"
• Screw (throttle shaft) "2"
Install the valve lever rollers "3" into
the slits "a" of the throttle valve.
10. Install:
• Starter jet "1"
• Pilot jet "2"
• Spacer "3"
• Needle jet "4"
• Main jet "5"
13. Install:
• O-ring
• Leak jet "1"
• Float chamber "2"
• Bolt (float chamber) "3"
• Cable holder (throttle stop screw
cable) "4"
• Hose holder (carburetor breather
hose) "5"
4-12
CARBURETOR
17. Install:
• O-ring "1"
• Valve lever housing cover "2"
• Bolt (valve lever housing cover)
"3"
c. Gradually turn out the adjusting
screw while moving the link lever
until it has no more free play.
INSTALLING THE CARBURETOR
1. Install:
• Carburetor joint "1"
Carburetor joint:
10 Nm (1.0 m•kg, 7.2
ft•lb)
18. Install:
• Carburetor breather hose "1"
Install the carburetor breather hoses
to the carburetor so that the hoses do
not bend near where they are installed.
5. Install:
• Throttle cable (pull) "1"
Throttle cable (pull):
4 Nm (0.4 m•kg, 2.9
ft•lb)
• Throttle cable (return) "2"
Throttle cable (return):
11 Nm (1.1 m•kg, 8.0
ft•lb)
2. Install:
• Carburetor "1"
Install the projection "a" between the
carburetor joint slots.
ADJUSTING THE ACCELERATOR
PUMP TIMING
Adjustment steps:
In order for the throttle valve height
"a" to achieve the specified value,
tuck under the throttle valve plate "1"
the rod "2" etc. with the same outer diameter as the specified value.
3. Install:
• Hot starter plunger "1"
Hot starter plunger:
2 Nm (0.2 m•kg, 1.4
ft•lb)
6. Adjust:
• Throttle grip free play
Refer to "ADJUSTING THE
THROTTLE CABLE FREE PLAY"
section in the CHAPTER 3.
7. Install:
• Throttle cable cover "1"
• Bolt (throttle cable cover) "2"
Bolt (throttle cable cover):
4 Nm (0.4 m•kg, 2.9
ft•lb)
Throttle valve height:
0.8 mm (0.031 in)
4. Tighten:
• Bolt (carburetor joint) "1"
a. Fully turn in the accelerator pump
adjusting screw "3".
b. Check that the link lever "4" has
free play "b" by pushing lightly on
it.
Bolt (carburetor joint):
3 Nm (0.3 m•kg, 2.2
ft•lb)
• Bolt (air filter joint) "2"
Bolt (air filter joint):
3 Nm (0.3 m•kg, 2.2
ft•lb)
4-13
8. Install:
• Throttle position sensor lead coupler "1"
• Clamp "2"
Refer to "CABLE ROUTING DIAGRAM" section in the CHAPTER
2.
CAMSHAFTS
CAMSHAFTS
REMOVING THE CYLINDER HEAD COVER
Order
Part name
Q'ty
Remarks
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section.
Seat and fuel tank
1
Spark plug
1
2
Cylinder head breather hose
1
3
Bolt (cylinder head cover)
2
4
Cylinder head cover
1
5
Cylinder head cover gasket
1
6
Timing chain guide (top side)
1
4-14
CAMSHAFTS
REMOVING THE CAMSHAFTS
Order
Part name
Q'ty
Remarks
1
Timing mark accessing screw
1
Refer to removal section.
2
Crankshaft end accessing screw
1
Refer to removal section.
3
Timing chain tensioner cap bolt
1
Refer to removal section.
4
Timing chain tensioner
1
Refer to removal section.
5
Camshaft cap
2
Refer to removal section.
6
Clip
2
Refer to removal section.
7
Exhaust camshaft
1
Refer to removal section.
8
Intake camshaft
1
Refer to removal section.
4-15
CAMSHAFTS
REMOVING THE CAMSHAFT
1. Remove:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw
"2"
4.
•
•
•
Remove:
Bolt (camshaft cap) "1"
Camshaft cap "2"
Clip
2. Align:
• T.D.C. mark
With align mark.
Remove the bolts (camshaft cap) in a
crisscross pattern, working from the
outside in.
Checking steps:
a. Turn the crankshaft counterclockwise with a wrench.
b. Align the T.D.C. mark "a" on the
rotor with the align mark "b" on the
crankcase cover when piston is at
T.D.C. on compression stroke.
The bolts (camshaft cap) must be
removed evenly to prevent damage to the cylinder head, camshafts or camshaft caps.
In order to be sure that the piston is at
Top Dead Center, the punch mark "c"
on the exhaust camshaft and the
punch mark "d" on the intake camshaft must align with the cylinder
head surface, as shown in the illustration.
Cam lobes length:
Intake "a":
30.330–30.430 mm
(1.1941–1.1980 in)
<Limit>:
30.230 mm (1.1902 in)
Intake "b":
22.45–22.55 mm
(0.8839–0.8878 in)
<Limit>:
22.35 mm (0.8799 in)
Exhaust "a":
30.399–30.499 mm
(1.1968–1.2007 in)
<Limit>:
30.299 mm (1.1929 in)
Exhaust "b":
22.45–22.55 mm
(0.8839–0.8878 in)
<Limit>:
22.35 mm (0.8799 in)
5. Remove:
• Exhaust camshaft "1"
• Intake camshaft "2"
Attach a wire "3" to the timing chain to
prevent it from falling into the crankcase.
3. Measure:
• Runout (camshaft)
Out of specification → Replace.
Runout (camshaft):
Less than 0.03 mm
(0.0012 in)
3. Remove:
• Timing chain tensioner cap bolt
"1"
• Timing chain tensioner "2"
• Gasket
CHECKING THE CAMSHAFT
1. Inspect:
• Cam lobe
Pitting/scratches/blue discoloration → Replace.
2. Measure:
• Cam lobe length "a" and "b"
Out of specification → Replace.
4-16
CAMSHAFTS
4. Measure:
• Camshaft-to-cap clearance
Out of specification → Measure
camshaft outside diameter.
Camshaft-to-cap clearance:
0.028–0.062 mm
(0.0011–0.0024 in)
<Limit>:0.08 mm (0.003
in)
Measurement steps:
a. Install the camshaft onto the cylinder head.
b. Position a strip of Plastigauge®
"1" onto the camshaft.
c. Install the clip, dowel pins and
camshaft caps.
Bolt (camshaft cap):
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Tighten the bolts (camshaft cap) in
a crisscross pattern from innermost
to outer caps.
• Do not turn the camshaft when
measuring clearance with the
Plastigauge®.
CHECKING THE CAMSHAFT
SPROCKET
1. Inspect:
• Camshaft sprocket "1"
Wear/damage → Replace the
camshaft assembly and timing
chain as a set.
INSTALLING THE CAMSHAFT
1. Install:
• Exhaust camshaft "1"
• Intake camshaft "2"
CHECKING THE
DECOMPRESSION SYSTEM
1. Check:
• Decompression system
Checking steps:
a. Check that the decompression
mechanism cam "1" moves
smoothly.
b. Check that the decompression
mechanism cam lever pin "2" projects from the camshaft.
d. Remove the camshaft caps and
measure the width of the Plastigauge® "1".
5. Measure:
• Camshaft outside diameter "a"
Out of specification→Replace the
camshaft.
Within specification → Replace
camshaft case and camshaft
caps as a set.
CHECKING THE TIMING CHAIN
TENSIONER
1. Check:
• While pressing the tensioner rod
lightly with fingers, use a thin
screwdriver "1" and wind the tensioner rod up fully clockwise.
• When releasing the screwdriver
by pressing lightly with fingers,
make sure that the tensioner rod
will come out smoothly.
• If not, replace the tensioner assembly.
Camshaft outside diameter:
21.959–21.972 mm
(0.8645–0.8650 in)
4-17
Installation steps:
a. Turn the crankshaft counterclockwise with a wrench.
• Apply the molybdenum disulfide oil
on the camshafts.
• Apply the engine oil on the decompression system.
• Squeezing the decompression lever allows the crankshaft to be
turned easily.
b. Align the T.D.C. mark "a" on the
rotor with the align mark "b" on the
crankcase cover when piston is at
T.D.C. on compression stroke.
CAMSHAFTS
c. Fit the timing chain "3" onto both
camshaft sprockets and install the
camshafts on the cylinder head.
The camshafts should be installed
onto the cylinder head so that the
punch mark "c" on the exhaust camshaft and the punch mark "d" on the
intake camshaft must align with the
cylinder head surface, as shown in
the illustration.
Do not turn the crankshaft during
the camshaft installation. Damage
or improper valve timing will result.
d. Install the clips, camshaft caps "4"
and bolts (camshaft cap) "5".
2. Install:
• Timing chain tensioner
Installation steps:
a. While pressing the tensioner rod
lightly with fingers, use a thin
screwdriver and wind the tensioner rod up fully clockwise.
b. With the rod fully wound and the
chain tensioner UP mark "a" facing upward, install the gasket "1"
and the timing chain tensioner "2",
and tighten the bolt "3" to the
specified torque.
Bolt (timing chain tensioner):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Bolt (camshaft cap):
10 Nm (1.0 m•kg, 7.2
ft•lb)
The bolts (camshaft cap) must be
tightened evenly, or damage to the
cylinder head, camshaft caps, and
camshaft will result.
6.
•
•
•
•
Install:
Timing chain guide (top side) "1"
Cylinder head cover gasket "2"
Cylinder head cover "3"
Bolt (cylinder head cover) "4"
Bolt (cylinder head cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Apply the sealant on the cylinder
head cover gasket.
c. Release the screwdriver, check
the tensioner rod to come out and
tighten the gasket "4" and the cap
bolt "5" to the specified torque.
• Before installing the clips, cover the
cylinder head with a clean rag to
prevent the clips from into the cylinder head cavity.
• Apply the molybdenum disulfide oil
on the thread of the bolts (camshaft
cap).
• Tighten the bolts to the specified
torque in two or three steps in the
proper tightening sequence as
shown.
4. Check:
• Rotor T.D.C. mark
Align with the crankcase align
mark.
• Camshaft match marks
Align with the cylinder head surface.
Out of alignment → Adjust.
5. Install:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw
"2"
YAMAHA Bond No. 1215
(ThreeBond® No. 1215):
90890-85505
Tensioner cap bolt:
7 Nm (0.7 m•kg, 5.1
ft•lb)
3. Turn:
• Crankshaft
Counterclockwise several turns.
7. Install:
• Cylinder head breather hose
• Spark plug
Spark plug:
13 Nm (1.3 m•kg, 9.4
ft•lb)
4-18
CYLINDER HEAD
CYLINDER HEAD
REMOVING THE CYLINDER HEAD
Order
1
Part name
Q'ty
Remarks
Seat and fuel tank
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section.
Exhaust pipe and silencer
Refer to "EXHAUST PIPE AND SILENCER"
section.
Radiator hose 1
Disconnect at cylinder head side.
Carburetor
Refer to "CARBURETOR" section.
Camshaft
Refer to "CAMSHAFTS" section.
Upper engine bracket
Refer to "ENGINE REMOVAL" section.
Radiator pipe
1
2
Oil delivery pipe
1
3
Nut
2
4
Bolt [L = 135 mm (5.31 in)]
2
5
Bolt [L = 145 mm (5.71 in)]
2
6
Cylinder head
1
7
Timing chain guard (exhaust side)
1
4-19
CYLINDER HEAD
CHECKING THE CYLINDER HEAD
1. Eliminate:
• Carbon deposits (from the combustion chambers)
Use a rounded scraper.
Do not use a sharp instrument to
avoid damaging or scratching:
• Spark plug threads
• Valve seats
INSTALLING THE CYLINDER
HEAD
1. Install:
• Dowel pin "1"
• Cylinder head gasket "2"
• Timing chain guide (exhaust side)
"3"
• Cylinder head "4"
While pulling up the timing chain, install the timing chain guide (exhaust
side) and cylinder head.
3.
•
•
•
Install:
Copper washer "1"
Oil delivery pipe "2"
Union bolt (M8) "3"
Union bolt (M8):
18 Nm (1.8 m•kg, 13
ft•lb)
• Union bolt (M10) "4"
2. Inspect:
• Cylinder head
Scratches/damage → Replace.
Replace the titanium valves with the
cylinder head.
Refer to "CHECKING THE
VALVE".
3. Measure:
• Cylinder head warpage
Out of specification → Resurface.
Cylinder head warpage:
Less than 0.05 mm
(0.002 in)
Warpage measurement and resurfacing steps:
a. Place a straightedge and a feeler
gauge across the cylinder head.
b. Use a feeler gauge to measure
the warpage.
c. If the warpage is out of specification, resurface the cylinder head.
d. Place a 400–600 grit wet sandpaper on the surface plate, and resurface the head using a figureeight sanding pattern.
Union bolt (M10):
20 Nm (2.0 m•kg, 14
ft•lb)
2.
•
•
•
Install:
Washer "1"
Cable guide "2"
Bolts [L = 145 mm (5.71 in)] "3"
Bolts [L = 145 mm (5.71
in)]:
38 Nm (3.8 m•kg, 27
ft•lb)
First tighten the union bolts temporarily. Then retighten them with the width
"a" across flats of the oil delivery pipe
held tight with a spanner.
• Bolts [L = 135 mm (5.31 in)] "4"
Bolts [L = 135 mm (5.31
in)]:
38 Nm (3.8 m•kg, 27
ft•lb)
• Nuts "5"
Nuts:
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Apply the molybdenum disulfide
grease on the thread and contact
surface of the bolts.
• Follow the numerical order shown
in the illustration. Tighten the bolts
and nuts in two stages.
To ensure an even surface rotate the
cylinder head several times.
4-20
4. Install:
• Radiator pipe "1"
• Bolt (radiator pipe) "2"
Bolt (radiator pipe):
10 Nm (1.0 m•kg, 7.2
ft•lb)
VALVES AND VALVE SPRINGS
VALVES AND VALVE SPRINGS
REMOVING THE VALVES AND VALVE SPRINGS
Order
Part name
Q'ty
Cylinder head
Remarks
Refer to "CYLINDER HEAD" section.
1
Valve lifter
5
Refer to removal section.
2
Adjusting pad
5
Refer to removal section.
3
Valve cotter
10
Refer to removal section.
4
Valve spring retainer
5
5
Valve spring
5
6
Valve stem seal
5
7
Valve spring seat
5
8
Exhaust valve
2
9
Intake valve
3
4-21
VALVES AND VALVE SPRINGS
REMOVING THE VALVE LIFTER
AND VALVE COTTER
1. Remove:
• Valve lifter "1"
• Pad "2"
Identify each lifter "1" and pad "2" position very carefully so that they can
be reinstalled in their original place.
CHECKING THE VALVE
1. Measure:
• Stem-to-guide clearance
b. Install the new valve guide using a
valve guide remover "1" and valve
guide installer "2".
Stem-to-guide clearance = valve
guide inside diameter "a" valve stem diameter "b"
Out of specification→Replace the
valve guide.
2. Check:
• Valve sealing
Leakage at the valve seat → Inspect the valve face, valve seat
and valve seat width.
Checking steps:
a. Pour a clean solvent "1" into the
intake and exhaust ports.
b. Check that the valve seals properly.
There should be no leakage at the
valve seat "2".
Clearance (stem to
guide):
Intake:
0.010–0.037 mm
(0.0004–0.0015 in)
<Limit>:0.08 mm
(0.003 in)
Exhaust:
0.025–0.052 mm
(0.0010–0.0020 in)
<Limit>:0.10 mm
(0.004 in)
2. Replace:
• Valve guide
3. Remove:
• Valve cotter
Replacement steps:
Attach a valve spring compressor "1"
between the valve spring retainer and
the cylinder head to remove the valve
cotters.
To ease guide removal, installation
and to maintain correct fit heat the
cylinder head in an over to 100 °C
(212 °F).
Valve spring compressor:
YM-4019/90890-04019
a. Remove the valve guide using a
valve guide remover "1".
4-22
c. After installing the valve guide,
bore the valve guide using a valve
guide reamer "3" to obtain proper
stem-to-guide clearance.
Valve guide remover:
Intake:4.0 mm (0.16 in)
YM-4111/90890-04111
Exhaust:4.5 mm (0.18
in)
YM-4116/90890-04116
Valve guide installer:
Intake:4.0 mm (0.16 in)
YM-4112/90890-04112
Exhaust:4.5 mm (0.18
in)
YM-4117/90890-04117
Valve guide reamer:
Intake:4.0 mm (0.16 in)
YM-4113/90890-04113
Exhaust:4.5 mm (0.18
in)
YM-4118/90890-04118
After replacing the valve guide reface
the valve seat.
3. Inspect:
• Valve face
Pitting/wear → Grind the face.
• Valve stem end
Mushroom shape or diameter
larger than the body of the stem →
Replace.
VALVES AND VALVE SPRINGS
4. Measure:
• Margin thickness "a"
Out of specification → Replace.
Do not let the compound enter the
gap between the valve stem and
the guide.
Margin thickness:
Intake:
0.8 mm (0.0315 in)
Exhaust:
0.7 mm (0.0276 in)
Measurement steps:
a. Apply Mechanic's blueing dye
(Dykem) "b" to the valve face.
b. Apply molybdenum disulfide oil to
the valve stem.
5. Measure:
• Runout (valve stem)
Out of specification → Replace.
Runout limit:
0.01 mm (0.0004 in)
• When installing a new valve always
replace the guide.
• If the valve is removed or replaced
always replace the oil seal.
6. Eliminate:
• Carbon deposits
(from the valve face and valve
seat)
7. Inspect:
• Valve seat
Pitting/wear → Reface the valve
seat.
8. Measure:
• Valve seat width "a"
Out of specification → Reface the
valve seat.
Valve seat width:
Intake:
0.9–1.1 mm
(0.0354–0.0433 in)
<Limit>:1.6 mm
(0.0630 in)
Exhaust:
0.9–1.1 mm
(0.0354–0.0433 in)
<Limit>:1.6 mm
(0.0630 in)
b. Install the valve into the cylinder
head.
c. Press the valve through the valve
guide and onto the valve seat to
make a clear pattern.
d. Measure the valve seat width.
Where the valve seat and valve
face made contact, blueing will
have been removed.
e. If the valve seat is too wide, too
narrow, or the seat is not centered, the valve seat must be
refaced.
c. Install the valve into the cylinder
head.
d. Turn the valve until the valve face
and valve seat are evenly polished, then clean off all of the
compound.
For best lapping results, lightly tap
the valve seat while rotating the valve
back and forth between your hands.
9. Lap:
• Valve face
• Valve seat
This model uses titanium intake
and exhaust valves. Titanium
valves that have been used to lap
the valve seats must not be used.
Always replace lapped valves with
new valves.
• When replacing the cylinder head,
replace the valves without lapping
the valve seats and valve faces.
• When replacing the valves or valve
guides, use new valves to lap the
valve seats, and then replace them
with new valves.
Lapping steps:
a. Apply a coarse lapping compound
to the valve face.
4-23
e. Apply a fine lapping compound to
the valve face and repeat the
above steps.
After every lapping operation be sure
to clean off all of the compound from
the valve face and valve seat.
f.
Apply Mechanic's blueing dye
(Dykem) to the valve face.
g. Install the valve into the cylinder
head.
h. Press the valve through the valve
guide and onto the valve seat to
make a clear pattern.
i. Measure the valve seat width
again. If the valve seat width is out
of specification, reface and relap
the valve seat.
VALVES AND VALVE SPRINGS
CHECKING THE VALVE SPRINGS
1. Measure:
• Valve spring free length "a"
Out of specification → Replace.
Free length (valve
spring):
Intake:
39.76 mm (1.57 in)
<Limit>: 38.76 mm
(1.53 in)
Exhaust:
37.78 mm (1.49 in)
<Limit>: 36.78 mm
(1.45 in)
2. Measure:
• Compressed spring force "a"
Out of specification → Replace.
Compressed spring
force:
Intake:
99–114 N at 28.98 mm
(9.9–11.4 kg at 28.98
mm, 22.27–25.57 lb at
1.14 in)
Exhaust:
126–145 N at 28.30
mm (12.6–14.5 kg at
28.30 mm,
28.44–31.97 lb at 1.11
in)
3. Install:
• Valve cotter
While compressing the valve spring
with a valve spring compressor "1" install the valve cotters.
CHECKING THE VALVE LIFTERS
1. Inspect:
• Valve lifter
Scratches/damage → Replace
both lifters and cylinder head.
INSTALLING THE VALVES
1. Apply:
• Molybdenum disulfide oil
Onto the valve stem and valve
stem seal.
2. Install:
• Valve "1"
• Valve spring seat "2"
• Valve stem seal "3"
• Valve spring "4"
• Valve spring retainer "5"
To cylinder head.
• Make sure that each valve is installed in its original place, also referring to the painted color as
follows.
Intake (middle) "a": Sky blue
Intake (right/left) "b": not paint
Exhaust "c": Purple
• Install the valve springs with the
larger pitch "d" facing upward.
b. Installed length
3. Measure:
• Spring tilt "a"
Out of specification → Replace.
Spring tilt limit:
Intake:
2.5°/1.7 mm (0.067 in)
Exhaust:
2.5°/1.6 mm (0.063 in)
e.
Smaller pitch
4-24
Valve spring compressor:
YM-4019/90890-04019
4. To secure the valve cotters onto
the valve stem, lightly tap the
valve tip with a piece of wood.
Hitting the valve tip with excessive
force could damage the valve.
5. Install:
• Adjusting pad "1"
• Valve lifter "2"
• Apply the molybdenum disulfide oil
on the valve stem end.
• Apply the engine oil on the valve lifters.
• Valve lifter must turn smoothly
when rotated with a finger.
• Be careful to reinstall valve lifters
and pads in their original place.
CYLINDER AND PISTON
CYLINDER AND PISTON
REMOVING THE CYLINDER AND PISTON
Order
Part name
Q'ty
Cylinder head
Remarks
Refer to "CYLINDER HEAD" section.
1
Bolt (cylinder)
1
2
Cylinder
1
3
Piston pin clip
2
Refer to removal section.
4
Piston pin
1
Refer to removal section.
5
Piston
1
Refer to removal section.
6
Piston ring set
1
Refer to removal section.
4-25
CYLINDER AND PISTON
REMOVING THE PISTON AND
PISTON RING
1. Remove:
• Piston pin clip "1"
• Piston pin "2"
• Piston "3"
• Put identification marks on each
piston head for reference during reinstallation.
• Before removing each piston pin,
deburr the clip groove and pin hole
area. If the piston pin groove is deburred and the piston pin is still difficult to remove, use the piston pin
puller set "4".
Piston pin puller set:
YU-1304/90890-01304
Do not use a hammer to drive the
piston pin out.
CHECKING THE CYLINDER AND
PISTON
1. Inspect:
• Cylinder and piston walls
Vertical scratches → Replace cylinder and piston.
2. Measure:
• Piston-to-cylinder clearance
Measurement steps:
a. Measure the cylinder bore "C"
with a cylinder bore gauge.
Measure the cylinder bore "C" in parallel to and at right angles to the
crankshaft. Then, find the average of
the measurements.
Cylinder bore
"C"
77.00–77.01
mm
(3.0315–3.0319
in)
Taper limit "T"
0.05 mm (0.002
in)
Out of round
"R"
0.05 mm (0.002
in)
"C" = Maximum D
"T" = (Maximum D1 or D2) - (Maximum D5 or D6)
"R" = (Maximum D1, D3 or D5) (Minimum D2, D4 or D6)
a.
8 mm (0.31 in) from the piston
bottom edge
Piston size "P"
Standard
76.955–76.970
mm
(3.0297–3.0303
in)
d. If out of specification, replace the
piston and piston rings as a set.
e. Calculate the piston-to-cylinder
clearance with following formula:
Piston-to-cylinder clearance =
Cylinder bore "C" - Piston skirt
diameter "P"
Piston-to-cylinder clearance:
0.030–0.055 mm
(0.0012–0.0022 in)
<Limit>:0.1 mm (0.004
in)
f.
If out of specification, replace the
cylinder, and replace the piston
and piston rings as set.
CHECKING THE PISTON RING
1. Measure:
• Ring side clearance
Use a feeler gauge "1".
Out of specification→Replace the
piston and rings as a set.
Clean carbon from the piston ring
grooves and rings before measuring
the side clearance.
Side clearance:
2. Remove:
• Piston ring "1"
Spread the end gaps apart while at
the same time lifting the piston ring
over the top of the piston crown, as
shown in the illustration.
b. If out of specification, replace the
cylinder, and replace the piston
and piston rings as set.
c. Measure the piston skirt diameter
"P" with a micrometer.
4-26
Standard
<Limit>
Top
ring
0.030–0.065
mm
(0.0012–0.0026
in)
0.12
mm
(0.005
in)
2nd
ring
0.020–0.055
mm
(0.0008–0.0022
in)
0.12
mm
(0.005
in)
CYLINDER AND PISTON
2. Position:
• Piston ring
(in cylinder)
2.
•
•
•
Insert a ring into the cylinder and
push it approximately 10 mm (0.39 in)
into the cylinder. Push the ring with
the piston crown so that the ring will
be at a right angle to the cylinder
bore.
Position:
Top ring
2nd ring
Oil ring
Offset the piston ring end gaps as
shown.
b. Measure the inside diameter (piston) "b".
Inside diameter (piston):
16.002–16.013 mm
(0.6300–0.6304 in)
a. 10 mm (0.39 in)
3. Measure:
• Ring end gap
Out of specification → Replace.
You cannot measure the end gap on
the expander spacer of the oil control
ring. If the oil control ring rails show
excessive gap, replace all three rings.
End gap:
Standard
<Limit>
Top
ring
0.15–0.25 mm
(0.006–0.010 in)
0.50
mm
(0.020
in)
2nd
ring
0.30–0.45 mm
(0.012–0.018 in)
0.80
mm
(0.031
in)
Oil
ring
0.10–0.40 mm
(0.004–0.016 in)
—
CHECKING THE PISTON PIN
1. Inspect:
• Piston pin
Blue discoloration/grooves → Replace, then inspect the lubrication
system.
2. Measure:
• Piston pin-to-piston clearance
c. Calculate the piston pin-to-piston
clearance with the following formula.
Piston pin-to-piston clearance =
Inside diameter (piston) "b" Outside diameter (piston pin)
"a"
d. If out of specification, replace the
piston.
Piston pin-to-piston
clearance:
0.002–0.022 mm
(0.0001–0.0009 in)
<Limit>:0.07 mm (0.003
in)
3.
•
•
•
a. Top ring end
b. 2nd ring end
c. Oil ring end (upper)
d. Oil ring
e. Oil ring end (lower)
Install:
Piston "1"
Piston pin "2"
Piston pin clip "3"
• Apply engine oil onto the piston pin
and piston.
• Be sure that the arrow mark "a" on
the piston points to the exhaust side
of the engine.
• Before installing the piston pin clip,
cover the crankcase with a clean
rag to prevent the piston pin clip
from falling into the crankcase.
• Install the piston pin clips with their
ends facing downward.
INSTALLING THE PISTON RING
AND PISTON
1. Install:
• Piston ring
Onto the piston.
• Be sure to install the piston rings so
that the manufacturer's marks or
numbers are located on the upper
side of the rings.
• Lubricate the piston and piston
rings liberally with engine oil.
Measurement steps:
a. Measure the outside diameter
(piston pin) "a".
If out of specification, replace the
piston pin.
Outside diameter (piston
pin):
15.991–16.000 mm
(0.6296–0.6299 in)
4-27
New
CYLINDER AND PISTON
INSTALLING THE CYLINDER
1. Lubricate:
• Piston
• Piston ring
• Cylinder
Apply a liberal coating of engine oil.
2. Install:
• Dowel pin "1"
• O-ring "2"
Apply the lithium soap base grease
on the O-ring.
3. Install:
• Cylinder gasket "1"
• Cylinder "2"
Install the cylinder with one hand
while compressing the piston rings
with the other hand.
• Pass the timing chain "3"
through the timing chain cavity.
• Be careful not to damage the timing chain guide "4" during installation.
4. Install:
• Bolt (cylinder) "5"
Bolt (cylinder):
10 Nm (1.0 m•kg, 7.2
ft•lb)
4-28
CLUTCH
CLUTCH
REMOVING THE CLUTCH
Order
1
Part name
Q'ty
Remarks
Drain the engine oil.
Refer to "CHANGING THE ENGINE OIL"
section in the CHAPTER 3.
Brake pedal
Refer to "ENGINE REMOVAL" section.
Clutch cable
Disconnect at engine side.
Clutch cover
1
2
Clutch spring
5
3
Pressure plate
1
4
Push rod 1
1
5
Circlip
1
6
Washer
1
7
Bearing
1
8
Ball
1
9
Push rod 2
1
10
Friction plate
9
11
Clutch plate
8
12
Nut (clutch boss)
1
Refer to removal section.
13
Lock washer
1
Refer to removal section.
4-29
CLUTCH
Order
Part name
Q'ty
14
Clutch boss
1
15
Thrust washer
1
16
Primary driven gear
1
17
Spacer
1
18
Washer
1
19
Push lever shaft
1
4-30
Remarks
Refer to removal section.
CLUTCH
REMOVING THE CLUTCH BOSS
1. Remove:
• Nut "1"
• Lock washer "2"
• Clutch boss "3"
Straighten the lock washer tab and
use the clutch holding tool "4" to hold
the clutch boss.
Clutch holding tool:
YM-91042/90890-04086
CHECKING THE CLUTCH
SPRINGS
1. Measure:
• Clutch spring free length "a"
Out of specification → Replace
springs as a set.
Clutch spring free
length:
35.7 mm (1.41 in)
<Limit>: 34.7 mm (1.37
in)
CHECKING THE FRICTION
PLATES
1. Measure:
• Friction plate thickness
Out of specification → Replace
friction plate as a set.
Measure at all four points.
A. For USA and CDN
B. Except for USA and CDN
CHECKING THE CLUTCH
HOUSING AND BOSS
1. Inspect:
• Clutch housing "1"
Cracks/wear/damage → Replace.
• Clutch boss "2"
Scoring/wear/damage→Replace.
CHECKING THE PRIMARY DRIVEN
GEAR
1. Check:
• Circumferential play
Free play exists → Replace.
• Gear teeth "a"
Wear/damage → Replace.
CHECKING THE PUSH LEVER
SHAFT
1. Inspect:
• Push lever shaft "1"
Wear/damage → Replace.
Friction plate thickness:
2.9–3.1 mm
(0.114–0.122 in)
<Limit>: 2.8 mm (0.110
in)
CHECKING THE PUSH ROD
1. Inspect:
• Push rod 1 "1"
• Bearing "2"
• Washer "3"
• Push rod 2 "4"
• Ball "5"
Wear/damage/bend → Replace.
INSTALLING THE PUSH LEVER
SHAFT
1. Install:
• Push lever shaft "1"
• Bolt (push lever shaft) "2"
Bolt (push lever shaft):
10 Nm (1.0 m•kg, 7.2
ft•lb)
CHECKING THE CLUTCH PLATES
1. Measure:
• Clutch plate warpage
Out of specification → Replace
clutch plate as a set.
Use a surface plate "1" and thickness gauge "2".
Warp limit:
0.1 mm (0.004 in)
4-31
• Apply the lithium soap base grease
on the oil seal lip.
• Apply the engine oil on the push lever shaft.
• Fit the seat plate "3" in the groove
"a" of the push lever shaft and tighten the bolt (seat plate).
CLUTCH
INSTALLING THE CLUTCH
1. Install:
• Washer "1"
• Spacer "2"
• Primary driven gear "3"
• Thrust washer "4"
• Clutch boss "5"
Apply the engine oil on the primary
driven gear inner circumference.
2. Install:
• Lock washer "1"
• Nut (clutch boss) "2"
Nut (clutch boss):
75 Nm (7.5 m•kg, 54
ft•lb)
4. Install:
• Friction plate "1"
• Clutch plate 1 "2"
• Install the clutch plates and friction
plates alternately on the clutch
boss, starting with a friction plate
and ending with a friction plate.
• Apply the engine oil on the friction
plates and clutch plates.
5.
•
•
•
Install:
Bearing "1"
Washer "2"
Circlip "3"
To push rod 1 "4".
8. Install:
• Clutch spring "1"
• Bolt (clutch spring) "2"
Bolt (clutch spring):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Tighten the bolts in stage, using a
crisscross pattern.
9. Install:
• Dowel pin "1"
• Gasket (clutch cover) "2"
Apply the engine oil on the bearing
and washer.
Use the clutch holding tool "3" to hold
the clutch boss.
10. Install:
• Clutch cover "1"
• Bolt (clutch cover)
Clutch holding tool:
YM-91042/90890-04086
6.
•
•
•
Install:
Push rod 2 "1"
Ball "2"
Push rod 1 "3"
Apply the engine oil on the push rod
1, 2 and ball.
A. For USA and CDN
B. Except for USA and CDN
3. Bend the lock washer "1" tab.
7. Install:
• Pressure plate "1"
4-32
Bolt (clutch cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Tighten the bolts in stage, using a
crisscross pattern.
OIL FILTER ELEMENT AND WATER PUMP
OIL FILTER ELEMENT AND WATER PUMP
REMOVING THE OIL FILTER ELEMENT AND WATER PUMP
Order
Part name
Q'ty
Remarks
Drain the engine oil.
Refer to "CHANGING THE ENGINE OIL"
section in the CHAPTER 3.
Drain the coolant.
Refer to "CHANGING THE COOLANT" section in the CHAPTER 3.
Radiator hose 3
Disconnect at water pump side.
Exhaust pipe
Refer to "EXHAUST PIPE AND SILENCER"
section.
Brake pedal
Refer to "ENGINE REMOVAL" section.
Right engine guard
1
Oil filter element cover
1
2
Oil filter element
1
3
Water pump housing
1
4
Oil delivery pipe
1
5
Bolt (oil hose)
1
6
Kickstarter crank
1
7
Right crankcase cover
1
8
Impeller
1
4-33
Refer to removal section.
OIL FILTER ELEMENT AND WATER PUMP
Order
Part name
Q'ty
Remarks
9
Washer
1
Refer to removal section.
10
Impeller shaft
1
Refer to removal section.
11
Oil seal
2
Refer to removal section.
12
Bearing
1
Refer to removal section.
4-34
OIL FILTER ELEMENT AND WATER PUMP
REMOVING THE IMPELLER
SHAFT
1. Remove:
• Impeller "1"
• Washer "2"
• Impeller shaft "3"
CHECKING THE OIL DELIVERY
PIPE
1. Inspect:
• Oil delivery pipe "1"
Bend/damage → Replace.
Clogged → Blow.
CHECKING THE OIL SEAL
1. Inspect:
• Oil seal "1"
Wear/damage → Replace.
Hold the impeller shaft on its width
across the flats "a" with spanners,
etc. and remove the impeller.
CHECKING THE IMPELLER SHAFT
1. Inspect:
• Impeller shaft "1"
Bend/wear/damage → Replace.
Fur deposits → Clean.
REMOVING THE OIL SEAL
It is not necessary to disassemble the
water pump, unless there is an abnormality such as excessive change in
coolant level, discoloration of coolant,
or milky transmission oil.
CHECKING THE IMPELLER SHAFT
GEAR
1. Inspect:
• Gear teeth "a"
Wear/damage → Replace.
• Apply the lithium soap base grease
on the oil seal lip.
• Install the oil seal with its manufacture's marks or numbers facing the
right crankcase cover "2".
2. Install:
• Bearing "1"
Install the bearing by pressing its outer race parallel.
1. Remove:
• Bearing "1"
2. Remove:
• Oil seal "1"
INSTALLING THE OIL SEAL
1. Install:
• Oil seal "1"
CHECKING THE BEARING
1. Inspect:
• Bearing
Rotate inner race with a finger.
Rough spot/seizure → Replace.
4-35
OIL FILTER ELEMENT AND WATER PUMP
INSTALLING THE IMPELLER
SHAFT
1. Install:
• Impeller shaft "1"
• Washer "2"
• Impeller "3"
Impeller:
14 Nm (1.4 m•kg, 10
ft•lb)
• Take care so that the oil seal lip is
not damaged or the spring does not
slip off its position.
• When installing the impeller shaft,
apply the lithium soap base grease
on the oil seal lip and impeller shaft.
And install the shaft while turning it.
• Hold the impeller shaft on its width
across the flats "a" with spanners,
etc. and install the impeller.
2. Install:
• Right crankcase cover "1"
• Bolt (right crankcase cover) "2"
2. Install:
• Oil hose "1"
• Bolt (oil hose) "2"
Bolt (right crankcase
cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Apply the engine oil on the impeller
shaft end.
• Mesh the impeller shaft gear "3"
with primary drive gear "4".
• Tighten the bolts in stage, using a
crisscross pattern.
Bolt (oil hose):
8 Nm (0.8 m•kg, 5.8
ft•lb)
3.
•
•
•
Install:
Copper washer "1"
Oil delivery pipe "2"
Union bolt (M8) "3"
Union bolt (M8):
18 Nm (1.8 m•kg, 13
ft•lb)
• Union bolt (M10) "4"
Union bolt (M10):
20 Nm (2.0 m•kg, 14
ft•lb)
INSTALLING THE KICKSTARTER
CRANK
1. Install:
• Kickstarter crank "1"
• Washer
• Bolt (kickstarter crank)
INSTALLING THE RIGHT
CRANKCASE COVER
1. Install:
• Dowel pin "1"
• O-ring "2"
• Collar "3"
• Gasket "4"
Apply the lithium soap base grease
on the O-ring.
Bolt (kickstarter crank):
33 Nm (3.3 m•kg, 24
ft•lb)
Install so that the clearance "a" between the kickstarter crank and engine bracket mounting bolt is 8 mm
(0.31 in) or more and that the kickstarter crank does not contact the
right crankcase cover when it is
pulled out.
4-36
First tighten the union bolts temporarily. Then retighten them with the width
"a" across flats of the oil delivery pipe
held tight with a spanner.
OIL FILTER ELEMENT AND WATER PUMP
INSTALLING THE WATER PUMP
HOUSING
1. Install:
• Dowel pin "1"
• O-ring "2"
Apply the lithium soap base grease
on the O-ring.
2. Install:
• Water pump housing "1"
• Bolt (water pump housing) "2"
Bolt (water pump housing):
10 Nm (1.0 m•kg, 7.2
ft•lb)
INSTALLING THE OIL FILTER
ELEMENT
1. Install:
• Oil filter element "1"
• O-ring "2"
• Oil filter element cover "3"
• Bolt (oil filter element cover)
Bolt (oil filter element
cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Apply the lithium soap base grease
on the O-ring.
4-37
BALANCER
BALANCER
REMOVING THE BALANCER
Order
Part name
Q'ty
Remarks
Primary driven gear
Refer to "CLUTCH" section.
Right crankcase cover
Refer to "OIL FILTER ELEMENT AND WATER PUMP" section.
Stator
Refer to "CDI MAGNETO" section.
1
Nut (primary drive gear)
1
Refer to removal section.
2
3
Nut (balancer shaft driven gear)
1
Refer to removal section.
Lock washer
1
4
Primary drive gear
1
5
Balancer shaft drive gear
1
6
Lock washer
1
7
Balancer shaft driven gear
1
8
Balancer shaft
1
4-38
Refer to removal section.
BALANCER
REMOVING THE BALANCER
1. Straighten the lock washer tab.
2. Loosen:
• Nut (primary drive gear) "1"
• Nut (balancer shaft driven gear)
"2"
CHECKING THE BALANCER
SHAFT
1. Inspect:
• Balancer shaft
Cracks/damage → Replace.
Place an aluminum plate "a" between
the teeth of the balancer shaft drive
gear "3" and driven gear "4".
3. Install:
• Balancer shaft drive gear "1"
• Align the punched mark "a" on the
balancer shaft drive gear with the
punched mark "b" on the balancer
shaft driven gear "2".
• Align the punched mark "c" on the
balancer shaft drive gear with the
lower spline "d" on the crankshaft
end.
INSTALLING THE BALANCER
1. Install:
• Balancer shaft "1"
• Apply the engine oil on the bearing.
• When installing the balancer shaft,
align the center "a" of the balancer
shaft weight along the line connecting the centers of the crankshaft
and balancer shaft.
Nut (balancer shaft driven gear):
50 Nm (5.0 m•kg, 36
ft•lb)
3. Remove:
• Balancer shaft "1"
When removing the balancer shaft,
align the center "a" of the balancer
shaft weight along the line connecting
the centers of the crankshaft and balancer shaft.
4. Install:
• Lock washer "1"
• Nut (balancer shaft driven gear)
"2"
• Primary drive gear "3"
• Lock washer "4"
• Nut (primary drive gear) "5"
2. Install:
• Balancer shaft driven gear "1"
Install the balancer shaft driven gear
onto the balancer shaft while aligning
the punch mark "a" on the balancer
shaft driven gear with the lower spline
"b" on the balancer shaft end.
Nut (primary drive gear):
75 Nm (7.5 m•kg, 54
ft•lb)
• Install the primary drive gear with its
stepped side "a" facing the engine.
• Place an aluminum plate "b" between the teeth of the balancer
shaft drive gear "6" and driven gear
"7".
CHECKING THE PRIMARY DRIVE
GEAR, BALANCER SHAFT DRIVE
GEAR AND BALANCER SHAFT
DRIVEN GEAR
1. Inspect:
• Primary drive gear "1"
• Balancer shaft drive gear "2"
• Balancer shaft driven gear "3"
Wear/damage → Replace.
5. Bend the lock washer tab.
4-39
OIL PUMP
OIL PUMP
REMOVING THE OIL PUMP
Order
Part name
Q'ty
Remarks
Primary driven gear
Refer to "CLUTCH" section.
Right crankcase cover
Refer to "OIL FILTER ELEMENT AND WATER PUMP" section.
1
Circlip
1
2
Washer
1
3
Oil pump drive gear
1
4
Oil pump assembly
1
5
Outer rotor 2
1
6
Circlip
1
7
Inner rotor 2
1
8
Dowel pin
1
9
Oil pump cover
1
10
Outer rotor 1
1
11
Inner rotor 1
1
12
Dowel pin
1
13
Washer
1
14
Oil pump drive shaft
1
15
Rotor housing
1
4-40
OIL PUMP
REMOVING THE OIL TANK
Order
Part name
Q'ty
Remarks
Refer to "CHANGING THE ENGINE OIL"
section in the CHAPTER 3.
Drain the engine oil.
1
Oil hose 2
1
2
Oil hose 1
1
3
Dowel pin
2
4
Oil tank breather hose
1
5
Oil tank
1
6
Oil strainer
1
4-41
OIL PUMP
CHECKING THE OIL PUMP
1. Inspect:
• Oil pump drive gear "1"
• Oil pump drive shaft "2"
• Rotor housing "3"
• Oil pump cover "4"
Cracks/wear/damage → Replace.
2. Measure:
• Tip clearance "a"
(between the inner rotor "1" and
outer rotor "2")
• Side clearance "b"
(between the outer rotor "2" and
rotor housing "3")
• Housing and rotor clearance "c"
(between the rotor housing "3"
and rotors "1" "2")
Out of specification→Replace the
oil pump assembly.
Tip clearance "a":
0.12 mm or less (0.0047
in or less)
<Limit>: 0.20 mm
(0.008 in)
Side clearance "b":
0.09–0.17 mm
(0.0035–0.0067 in)
<Limit>: 0.24 mm
(0.009 in)
Housing and rotor clearance "c":
0.03–0.10 mm
(0.0012–0.0039 in)
<Limit>: 0.17 mm
(0.0067 in)
3. Check:
• Unsmooth→Repeat steps #1 and
#2 or replace the defective parts.
INSTALLING THE OIL PUMP
1. Install:
• Oil pump drive shaft "1"
• Washer "2"
• Dowel pin "3"
• Inner rotor 1 "4"
• Apply the engine oil on the oil pump
drive shaft and inner rotor 1.
• Fit the dowel pin into the groove in
the inner rotor 1.
4.
•
•
•
•
Install:
Outer rotor 2 "1"
Dowel pin "2"
Oil pump assembly "3"
Bolt (oil pump assembly)
[L = 25 mm (0.94 in)] "4"
Bolt (oil pump assembly):
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Bolt (oil pump assembly)
[L = 30 mm (1.18 in)] "5"
Bolt (oil pump assembly):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Apply the engine oil on the outer rotor
2.
2. Install:
• Outer rotor 1 "1"
Apply the engine oil on the outer rotor
1.
5.
•
•
•
3. Install:
• Oil pump cover "1"
• Screw (oil pump cover) "2"
Screw (oil pump cover):
1.7 Nm (0.17 m•kg, 1.2
ft•lb)
• Dowel pin "3"
• Inner rotor 2 "4"
• Circlip "5"
• Apply the engine oil on the inner rotor 2.
• Fit the dowel pin into the groove in
the inner rotor 2.
4-42
Install:
Oil pump drive gear "1"
Washer "2"
Circlip "3"
Apply the engine oil on the oil pump
drive gear inner circumference.
OIL PUMP
IINSTALLING THE OIL TANK
BREATHER HOSE
1. Install:
• Oil tank "1"
• Oil tank breather hose "2"
• Clamp "3"
Clamp:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Install the clamp so that it does not
contact the oil tank.
• Insert the oil tank breather hose so
that its end "a" comes where the oil
tank pipe begins to bend.
• Install the clamp 3 mm (0.12 in)
away from the oil tank breather
hose end "a".
4-43
KICK SHAFT AND SHIFT SHAFT
KICK SHAFT AND SHIFT SHAFT
REMOVING THE KICK SHAFT AND SHIFT SHAFT
Order
Part name
Q'ty
Oil pump
Remarks
Refer to "OIL PUMP" section.
1
Kick idle gear
1
2
Kick shaft assembly
1
3
Spring guide
1
4
Torsion spring
1
5
Ratchet wheel
1
6
Kick gear
1
7
Kick shaft
1
8
Washer
1
Refer to removal section.
9
Shift pedal
1
10
Shift shaft
1
11
Collar
1
12
Torsion spring
1
13
Roller
1
14
Shift guide
1
Refer to removal section.
15
Shift lever assembly
1
Refer to removal section.
16
Shift lever
1
4-44
KICK SHAFT AND SHIFT SHAFT
Order
Part name
Q'ty
17
Pawl
2
18
Pawl pin
2
19
Spring
2
20
Bolt (stopper lever)
1
21
Stopper lever
1
22
Torsion spring
1
23
Segment
1
4-45
Remarks
Refer to removal section.
KICK SHAFT AND SHIFT SHAFT
REMOVING THE KICK SHAFT
ASSEMBLY
1. Remove:
• Kick shaft assembly "1"
Unhook the torsion spring "2" from
the hole "a" in the crankcase.
REMOVING THE SHIFT GUIDE
AND SHIFT LEVER ASSEMBLY
1. Remove:
• Bolt (shift guide)
• Shift guide "1"
• Shift lever assembly "2"
The shift lever assembly is disassembled at the same time as the shift
guide.
REMOVING THE SEGMENT
1. Remove:
• Bolt (segment) "1"
• Segment "2"
Turn the segment counterclockwise
until it stops and loosen the bolt.
CHECKING THE KICK SHAFT AND
RATCHET WHEEL
1. Check:
• Ratchet wheel "1" smooth movement
Unsmooth movement → Replace.
• Kick shaft "2"
Wear/damage → Replace.
• Spring "3"
Broken → Replace.
CHECKING THE KICK GEAR, KICK
IDLE GEAR AND RATCHET
WHEEL
1. Inspect:
• Kick gear "1"
• Kick idle gear "2"
• Ratchet wheel "3"
• Gear teeth "a"
• Ratchet teeth "b"
Wear/damage → Replace.
CHECKING THE SHIFT GUIDE AND
SHIFT LEVER ASSEMBLY
1. Inspect:
• Shift guide "1"
• Shift lever "2"
• Pawl "3"
• Pawl pin "4"
• Spring "5"
Wear/damage → Replace.
CHECKING THE STOPPER LEVER
1. Inspect:
• Stopper lever "1"
Wear/damage → Replace.
• Torsion spring "2"
Broken → Replace.
INSTALLING THE SEGMENT
1. Install:
• Segment "1"
• Bolt (segment)
CHECKING THE SHIFT SHAFT
1. Inspect:
• Shift shaft "1"
Bend/damage → Replace.
• Spring "2"
Broken → Replace.
If the segment gets an impact, it
may be damaged. Take care not to
give an impact to the segment
when removing the bolt.
Bolt (segment):
30 Nm (3.0 m•kg, 22
ft•lb)
Align the notch "a" on the segment
with the pin "b" on the shift cam.
If the segment gets an impact, it
may be damaged. Take care not to
give an impact to the segment
when tightening the bolt.
4-46
KICK SHAFT AND SHIFT SHAFT
INSTALLING THE STOPPER
LEVER
1. Install:
• Torsion spring "1"
• Stopper lever "2"
• Bolt (stopper lever) "3"
Bolt (stopper lever):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Align the stopper lever roller with the
slot on segment.
INSTALLING THE SHIFT GUIDE
AND SHIFT LEVER ASSEMBLY
1. Install:
• Spring "1"
• Pawl pin "2"
• Pawl "3"
To shift lever "4".
Apply the engine oil on the spring,
pawl pin and pawl.
2. Install:
• Shift lever assembly "1"
To shift guide "2".
4. Install:
• Bolt (shift guide) "1"
Bolt (shift guide):
10 Nm (1.0 m•kg, 7.2
ft•lb)
INSTALLING THE SHIFT SHAFT
1. Install:
• Roller "1"
• Collar "2"
• Torsion spring "3"
• Shift shaft "4"
Apply the engine oil on the roller and
shift shaft.
INSTALLING THE KICK SHAFT
ASSEMBLY
1. Install:
• Kick gear "1"
• Washer "2"
• Circlip "3"
• Ratchet wheel "4"
• Spring "5"
• Washer "6"
• Circlip "7"
To kick shaft "8".
• Apply the molybdenum disulfide oil
on the inner circumferences of the
kick gear and ratchet wheel.
• Align the punch mark "a" on the
ratchet wheel with the punch mark
"b" on the kick shaft.
2. Install:
• Torsion spring "1"
To kick shaft "2".
Make sure the stopper "a" of the torsion spring fits into the hole "b" on the
kick shaft.
2. Install:
• Shift pedal "1"
• Bolt (shift pedal) "2"
Bolt (shift pedal):
12 Nm (1.2 m•kg, 8.7
ft•lb)
Install with the punch mark "a" on the
shift pedal in alignment with the
punch mark "b" on the shift shaft.
3. Install:
• Shift lever assembly "1"
• Shift guide "2"
• The shift lever assembly is installed
at the same time as the shift guide.
• Apply the engine oil on the bolt
(segment) shaft.
4-47
3. Install:
• Spring guide "1"
Slide the spring guide into the kick
shaft, make sure the groove "a" in the
spring guide fits on the stopper of the
torsion spring.
KICK SHAFT AND SHIFT SHAFT
4. Install:
• Kick shaft assembly "1"
• Washer "2"
• Apply the molybdenum disulfide
grease on the contacting surfaces
of the kick shaft stopper "a" and kick
shaft ratchet wheel guide "3".
• Apply the engine oil on the kick
shaft.
• Slide the kick shaft assembly into
the crankcase and make sure the
kick shaft stopper "a" fits into the
kick shaft ratchet wheel guide.
5. Hook:
• Torsion spring "1"
Turn the torsion spring clockwise and
hook into the proper hole "a" in the
crankcase.
INSTALLING THE KICK IDLE
GEAR
1. Install:
• Kick idle gear "1"
• Washer "2"
• Circlip "3"
• Apply the engine oil on the kick idle
gear inner circumference.
• Install the kick idle gear with its depressed side "a" toward you.
4-48
CDI MAGNETO
CDI MAGNETO
REMOVING THE CDI MAGNETO
Order
Part name
Q'ty
Remarks
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section.
Seat and fuel tank
Disconnect the CDI magneto lead.
Refer to "KICK SHAFT AND SHIFT SHAFT"
section.
Shift pedal
1
Left crankcase cover
1
2
Nut (rotor)
1
Refer to removal section.
3
Rotor
1
Refer to removal section.
4
Stator
1
5
Woodruff key
1
4-49
CDI MAGNETO
REMOVING THE ROTOR
1. Remove:
• Nut (rotor) "1"
• Washer "2"
Use the rotor holding tool "3".
CHECKING THE WOODRUFF KEY
1. Inspect:
• Woodruff key "1"
Damage → Replace.
Rotor holding tool:
YU-1235/90890-01235
3. Install:
• Washer "1"
• Nut (rotor) "2"
Nut (rotor):
56 Nm (5.6 m•kg, 40
ft•lb)
Use the rotor holding tool "3".
Rotor holding tool:
YU-1235/90890-01235
INSTALLING THE CDI MAGNETO
1. Install:
• Stator "1"
• Screw (stator) "2"
2. Remove:
• Rotor "1"
Use the flywheel puller "2".
Flywheel puller:
YM-1189/90890-01189
When installing the flywheel puller,
turn it counterclockwise.
Screw (stator):
10 Nm (1.0 m•kg,
7.2ft•lb)
• Apply the sealant on the grommet
of the CDI magneto lead.
• Tighten the screws using the T30
bit.
4. Connect:
• CDI magneto lead
Refer to "CABLE ROUTING DIAGRAM" section in the CHAPTER
2.
YAMAHA Bond No. 1215
(ThreeBond® No. 1215):
90890-85505
CHECKING THE CDI MAGNETO
1. Inspect:
• Rotor inner surface "a"
• Stator outer surface "b"
Damage→ Inspect the crankshaft
runout and crankshaft bearing.
If necessary, replace CDI magneto and/or stator.
5. Install:
• Dowel pin
• Gasket (left crankcase cover)
2. Install:
• Woodruff key "1"
• Rotor "2"
• Clean the tapered portions of the
crankshaft and rotor.
• When installing the woodruff key,
make sure that its flat surface "a" is
in parallel with the crankshaft center
line "b".
• When installing the rotor, align the
keyway "c" of the rotor with the
woodruff key.
4-50
• Left crankcase cover "1"
• Hose guide (cylinder head breather hose) "2"
• Bolt (left crankcase cover)
Bolt (left crankcase cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Tighten the bolts in stage, using a
crisscross pattern.
ENGINE REMOVAL
ENGINE REMOVAL
REMOVING THE ENGINE
Order
Part name
Q'ty
Hold the machine by placing the suitable stand
under the frame.
Refer to "HANDLING NOTE".
Seat and fuel tank
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section.
Carburetor
Refer to "CARBURETOR" section.
Exhaust pipe and silencer
Refer to "EXHAUST PIPE AND SILENCER"
section.
Clutch cable
Disconnect at the engine side.
Radiator
Refer to "RADIATOR" section.
Shift pedal
Refer to "KICK SHAFT AND SHIFT SHAFT"
section.
Cylinder head breather hose
Refer to "CAMSHAFTS" section.
Drain the engine oil.
Refer to "CHANGING THE ENGINE OIL"
section in the CHAPTER 3.
Oil hose and oil tank breather hose
Refer to "OIL PUMP" section.
Ignition coil
Disconnect the CDI magneto lead.
1
Remarks
Lower engine guard
1
4-51
ENGINE REMOVAL
Order
Part name
Q'ty
Remarks
2
Neutral switch
1
3
Drive chain sprocket cover
1
4
Nut (drive sprocket)
1
Refer to removal section.
5
Lock washer
1
Refer to removal section.
6
Drive sprocket
1
Refer to removal section.
7
Clip
1
8
Bolt (brake pedal)
1
9
Brake pedal
1
10
Upper engine bracket
2
11
Front engine bracket
2
12
Engine mounting bolt
3
13
Pivot shaft
1
Refer to removal section.
14
Engine
1
Refer to removal section.
4-52
ENGINE REMOVAL
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
REMOVING THE DRIVE
SPROCKET
1. Remove:
• Nut (drive sprocket) "1"
• Lock washer "2"
2. Remove:
• Engine "1"
From right side.
• Lower engine guard "11"
• Bolt (lower engine guard) "12"
Bolt (lower engine
guard):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Make sure that the couplers, hoses
and cables are disconnected.
• Apply the molybdenum disulfide
grease on the pivot shaft.
• Install the patch with the claw "a"
facing outside the chassis.
• Straighten the lock washer tab.
• Loosen the nut while applying the
rear brake.
INSTALLING THE ENGINE
1. Install:
• Engine "1"
Install the engine from right side.
• Pivot shaft "2"
M
Pivot shaft:
85 Nm (8.5 m•kg, 61
ft•lb)
2. Remove:
• Drive sprocket "1"
• Drive chain "2"
Remove the drive sprocket together
with the drive chain.
• Engine mounting bolt (lower) "3"
Engine mounting bolt
(lower):
53Nm (5.3 m•kg, 38
ft•lb)
• Front engine bracket "4"
• Bolt (front engine bracket) "5"
Bolt (front engine bracket):
34 Nm (3.4 m•kg, 24
ft•lb)
REMOVING THE ENGINE
1. Remove:
• Pivot shaft "1"
If the pivot shaft is pulled all the way
out, the swingarm will come loose. If
possible, insert a shaft of similar diameter into the other side of the swingarm to support it.
• Patch "6"
• Engine mounting bolt (front) "7"
Engine mounting bolt
(front):
53 Nm (5.3 m•kg, 38
ft•lb)
• Upper engine bracket "8"
• Bolt (upper engine bracket) "9"
Bolt (upper engine bracket):
34 Nm (3.4 m•kg, 24
ft•lb)
• Engine mounting bolt (upper) "10"
Engine mounting bolt
(upper):
55 Nm (5.5 m•kg, 40
ft•lb)
4-53
INSTALLING THE BRAKE PEDAL
1. Install:
• Spring "1"
• Brake pedal "2"
• O-ring "3"
• Bolt (brake pedal) "4"
Bolt (brake pedal):
26 Nm (2.6 m•kg, 19
ft•lb)
• Clip "5"
Apply the lithium soap base grease
on the bolt, O-rings and brake pedal
bracket.
ENGINE REMOVAL
INSTALLING THE DRIVE
SPROCKET
1. Install:
• Drive sprocket "1"
• Drive chain "2"
Install the drive sprocket together
with the drive chain.
INSTALLING THE NEUTRAL
SWITCH
1. Install:
• Spring "1"
• Pin "2"
• O-ring "3"
• Neutral switch "4"
• Screw (neutral switch) "5"
Screw (neutral switch):
4 Nm (0.4 m•kg, 2.9
ft•lb)
Apply the lithium soap base grease
on the O-ring.
2. Install:
• Lock washer "1"
• Nut (drive sprocket) "2"
Nut (drive sprocket):
75 Nm (7.5 m•kg, 54
ft•lb)
Tighten the nut while applying the
rear brake.
2. Install:
• Hose guide (cylinder head breather hose) "1"
• Bolt (hose guide) "2"
Bolt (hose guide):
10 Nm (1.0 m•kg, 7.2
ft•lb)
3. Bend the lock washer tab to lock
the nut.
4. Install:
• Drive chain sprocket guide "1"
• Drive chain sprocket cover "2"
• Bolt (drive chain sprocket cover)
"3"
Bolt (drive chain sprocket cover):
7 Nm (0.7 m•kg, 5.1
ft•lb)
4-54
CRANKCASE AND CRANKSHAFT
CRANKCASE AND CRANKSHAFT
REMOVING THE CRANKSHAFT
Order
Part name
Q'ty
Remarks
Engine
Refer to "ENGINE REMOVAL" section.
Piston
Refer to "CYLINDER AND PISTON" section.
Kick shaft assembly
Refer to "KICK SHAFT AND SHIFT SHAFT"
section.
Segment
Refer to "KICK SHAFT AND SHIFT SHAFT"
section.
Stator
Refer to "CDI MAGNETO" section.
Balancer shaft
Refer to "BALANCER" section.
1
Timing chain guide (intake side)
1
2
Timing chain
1
3
Oil delivery pipe 2
1
4
Bolt [L = 45 mm (1.77 in)]
6
Refer to removal section.
5
Bolt [L = 55 mm (2.17 in)]
1
Refer to removal section.
6
Bolt [L = 70 mm (2.76 in)]
4
Refer to removal section.
7
Hose guide
1
Refer to removal section.
8
Clutch cable holder
1
Refer to removal section.
9
Right crankcase
1
Refer to removal section.
4-55
CRANKCASE AND CRANKSHAFT
Order
Part name
Q'ty
10
Left crankcase
1
11
Oil strainer
1
12
Crankshaft
1
4-56
Remarks
Refer to removal section.
Refer to removal section.
CRANKCASE AND CRANKSHAFT
REMOVING THE CRANKCASE BEARING
Order
Part name
Q'ty
Remarks
Transmission
Refer to "TRANSMISSION, SHIFT CAM AND
SHIFT FORK" section.
Shift cam and shift fork
Refer to "TRANSMISSION, SHIFT CAM AND
SHIFT FORK" section.
1
Oil seal
2
2
Bearing
10
4-57
Refer to removal section.
CRANKCASE AND CRANKSHAFT
DISASSEMBLING THE
CRANKCASE
1. Separate:
• Right crankcase
• Left crankcase
Separation steps:
a. Remove the crankcase bolts "1",
hose guide "2" and clutch cable
holder "3".
REMOVING THE CRANKSHAFT
1. Remove:
• Crankshaft "1"
Use the crankcase separating
tool "2".
Crankcase separating
tool:
YU-1135-A/9089001135
CHECKING THE CRANKCASE
1. Inspect:
• Contacting surface "a"
Scratches → Replace.
• Engine mounting boss "b", crankcase
Cracks/damage → Replace.
Do not use a hammer to drive out
the crankshaft.
2. Inspect:
• Bearing
Rotate inner race with a finger.
Rough spot/seizure → Replace.
Loosen each bolt 1/4 of a turn at a
time and after all the bolts are loosened, remove them.
b. Remove the right crankcase "4".
• Place the crankcase with its left half
downward and split the right half
apart while lifting it horizontally by
lightly tapping the projection "a" on
it using a soft hammer.
• When splitting it, leave the crankshaft and transmission with the left
half.
Use soft hammer to tap on the
case half. Tap only on reinforced
portions of case. Do not tap on
gasket mating surface. Work slowly and carefully. Make sure the
case halves separate evenly. If the
cases do not separate, check for a
remaining case bolt or fitting. Do
not force.
c. Remove the dowel pins and Oring.
REMOVING THE CRANKCASE
BEARING
1. Remove:
• Bearing "1"
• Remove the bearing from the
crankcase by pressing its inner
race.
• Do not use the removed bearing.
CHECKING THE TIMING CHAIN
AND TIMING CHAIN GUIDE
1. Inspect:
• Timing chain
Cracks/stiff → Replace the timing
chain and camshaft sprocket as a
set.
2. Inspect:
• Timing chain guide
Wear/damage → Replace.
4-58
3. Inspect:
• Oil seal
Damage → Replace.
CHECKING THE CRANKSHAFT
1. Measure:
• Runout limit "a"
• Small end free play limit "b"
• Connecting rod big end side
clearance "c"
• Crank width "d"
Out of specification → Replace.
Use the dial gauge and a thickness gauge.
Dial gauge and stand:
YU-3097/90890-01252
Standard
Runo
0.03 mm (0.0012
ut limin)
it:
<Limit>
0.05
mm
(0.002
in)
Small
end
free
play:
0.4–1.0 mm
2.0 mm
(0.016–0.039 in) (0.08 in)
Side
clearance:
0.15–0.45 mm
0.50
(0.0059–0.0177
mm
in)
(0.02 in)
Crack
width:
55.95–56.00
mm
(2.203–2.205 in)
—
CRANKCASE AND CRANKSHAFT
• Screw [bearing stopper (crankshaft)] "1"
Screw [bearing stopper
(crankshaft)]:
14 Nm (1.4 m•kg, 10
ft•lb)
To left and right crankcase.
CHECKING THE OIL STRAINER
1. Inspect:
• Oil strainer
Damage → Replace.
CHECKING THE OIL DELIVERY
PIPE 2
1. Inspect:
• Oil delivery pipe 2 "1"
• O-ring "2"
Damage → Replace.
• Oil orifice "a"
Clogged → Blow.
INSTALLING THE CRANKCASE
BEARING
1. Install:
• Bearing
• Bearing stopper
• Bolt (bearing stopper)
Bolt (bearing stopper):
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Screw (bearing stopper)
Screw (bearing stopper):
10 Nm (1.0 m•kg, 7.2
ft•lb)
• Install the bearing by pressing its
outer race parallel.
• To prevent the screw [bearing stopper (crankshaft)] from becoming
loose, crush the screw head periphery "a" into the concave "b" using a
punch etc. In so doing, take care
not to damage the screwdriver receiving hole in the screw head.
INSTALLING THE CRANKSHAFT
1. Install:
• Crankshaft "1"
Use the crankshaft installing tool
"2", "3", "4" and "5".
Crankshaft installing pot
"2":
YU-90050/90890-01274
Crankshaft installing bolt
"3":
YU-90050/90890-01275
Adapter (M12) "4":
YU-90063/90890-01278
Spacer (crankshaft installer) "5":
YU-91044/90890-04081
• Hold the connecting rod at top dead
center with one hand while turning
the nut of the installing tool with the
other. Operate the installing tool until the crankshaft bottoms against
the bearing.
• Before installing the crankshaft,
clean the contacting surface of
crankcase.
Do not use a hammer to drive in
the crankshaft.
4-59
A. For USA and CDN
B. Except for USA and CDN
2. Check:
• Shifter operation
• Transmission operation
Unsmooth operation → Repair.
3. Install:
• Oil strainer "1"
• Bolt (oil strainer) "2"
Bolt (oil strainer):
10 Nm (1.0 m•kg, 7.2
ft•lb)
4. Apply:
• Sealant
On the right crankcase "1".
YAMAHA Bond No.1215
(ThreeBond® No.1215):
90890-85505
Clean the contacting surface of left
and right crankcase before applying
the sealant.
CRANKCASE AND CRANKSHAFT
Apply the lithium soap base grease
on the Orings.
5.
•
•
•
Install:
Dowel pin "1"
O-ring "2"
Right crankcase
To left crankcase.
• Apply the lithium soap base grease
on the O-ring.
• Fit the right crankcase onto the left
crankcase. Tap lightly on the case
with soft hammer.
• When installing the crankcase, the
connecting rod should be positioned at TDC (top dead center).
6.
•
•
•
Tighten:
Hose guide "1"
Clutch cable holder "2"
Bolt (crankcase) "3"
Bolt (crankcase):
12 Nm (1.2 m•kg, 8.7
ft•lb)
Tighten the crankcase tightening
bolts in stage, using a crisscross pattern.
7.
•
•
•
8. Install:
• Timing chain "1"
• Timing chain guide (intake side)
"2"
• Bolt (timing chain guide) "3"
Bolt (timing chain guide):
10 Nm (1.0 m•kg, 7.2
ft•lb)
9. Remove:
• Sealant
Forced out on the cylinder mating
surface.
10. Apply:
• Engine oil
To the crank pin, bearing and oil
delivery hole.
11. Check:
• Crankshaft and transmission operation.
Unsmooth operation → Repair.
Install:
Oil delivery pipe 2 "1"
O-ring "2"
Bolt (oil delivery pipe 2) "3"
Bolt (oil delivery pipe 2):
10 Nm (1.0 m•kg, 7.2
ft•lb)
4-60
TRANSMISSION, SHIFT CAM AND SHIFT FORK
TRANSMISSION, SHIFT CAM AND SHIFT FORK
REMOVING THE TRANSMISSION, SHIFT CAM AND SHIFT FORK
Order
Part name
Q'ty
Remarks
Engine
Refer to "ENGINE REMOVAL" section.
Separate the crankcase.
Refer to "CRANKCASE AND CRANKSHAFT" section.
1
Main axle
1
Refer to removal section.
2
Drive axle
1
Refer to removal section.
3
Shift cam
1
Refer to removal section.
4
Shift fork 3
1
Refer to removal section.
5
Shift fork 2
1
Refer to removal section.
6
Shift fork 1
1
Refer to removal section.
7
Collar
1
4-61
TRANSMISSION, SHIFT CAM AND SHIFT FORK
REMOVING THE TRANSMISSION
1. Remove:
• Main axle "1"
• Drive axle "2"
• Shift cam
• Shift fork 3
• Shift fork 2
• Shift fork 1
• Remove assembly with the collar
"3" installed to the crankcase.
• Remove assembly carefully. Note
the position of each part. Pay particular attention to the location and direction of shift forks.
• Remove the main axle, drive axle,
shift cam and shift fork all together
by tapping lightly on the transmission drive axle with a soft hammer.
CHECKING THE GEARS
1. Inspect:
• Matching dog "a"
• Gear teeth "b"
• Shift fork groove "c"
Wear/damage → Replace.
2. Inspect:
• O-ring "1"
Damage → Replace.
3. Check:
• Gears movement
Unsmooth movement→Repair or
replace.
CHECKING THE BEARING
1. Inspect:
• Bearing "1"
Rotate inner race with a finger.
Rough spot/seizure → Replace.
CHECKING THE SHIFT FORK,
SHIFT CAM AND SEGMENT
1. Inspect:
• Shift fork "1"
Wear/damage/scratches → Replace.
2. Inspect:
• Shift cam "1"
• Segment "2"
Wear/damage → Replace.
3. Check:
• Shift fork movement
Unsmooth operation → Replace
shift fork.
For a malfunctioning shift fork, replace not only the shift fork itself but
the two gears each adjacent to the
shift fork.
4-62
INSTALLING THE TRANSMISSION
1. Install:
• 5th pinion gear (24T) "1"
• 3rd pinion gear (18T) "2"
• Collar "3"
• 4th pinion gear (18T) "4"
• 2nd pinion gear (16T) "5"
To main axle "6".
Apply the molybdenum disulfide oil
on the inner and end surface of the
idler gear and on the inner surface of
the sliding gear, then install.
2.
•
•
•
•
•
•
Install:
2nd wheel gear (28T) "1"
4th wheel gear (22T) "2"
3rd wheel gear (26T) "3"
5th wheel gear (25T) "4"
1st wheel gear (30T) "5"
O-ring "6"
To drive axle "7".
• Apply the molybdenum disulfide oil
on the inner and end surface of the
idler gear and on the inner surface
of the sliding gear, then install.
• Apply the lithium soap base grease
on the O-ring.
TRANSMISSION, SHIFT CAM AND SHIFT FORK
3. Install:
• Washer "1"
• Circlip "2"
• Be sure the circlip sharp-edged corner "a" is positioned opposite side
to the washer and gear "b".
• Install the circlip with its ends "c"
settled evenly on the spline crests.
6. Install:
• Transmission assembly "1"
To left crankcase "2".
Apply the engine oil on the bearings
and guide bars.
4. Install:
• Collar "1"
• Apply the lithium soap base grease
on the oil seal lip.
• When installing the collar into the
crankcase, pay careful attention to
the crankcase oil seal lip.
5.
•
•
•
•
7. Check:
• Shifter operation
• Transmission operation
Unsmooth operation → Repair.
Install:
Shift fork 1 (L) "1"
Shift fork 2 (C) "2"
Shift fork 3 (R) "3"
Shift cam "4"
To main axle and drive axle.
• Apply the engine oil on the shift fork
grooves.
• Mesh the shift fork #1 (L) with the
4th wheel gear "5" and #3 (R) with
the 5th wheel gear "7" on the drive
axle.
• Mesh the shift fork #2 (C) with the
3rd pinion gear "6" on the main axle.
4-63
FRONT WHEEL AND REAR WHEEL
CHASSIS
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are requested not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.
FRONT WHEEL AND REAR WHEEL
REMOVING THE FRONT WHEEL
Order
Part name
Q'ty
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
1
Bolt (axle holder)
4
2
Nut (front wheel axle)
1
3
Front wheel axle
1
4
Front wheel
1
5
Collar
2
6
Oil seal
2
7
Bearing
2
8
Brake disc
1
5-1
Remarks
Only loosening.
Refer to removal section.
FRONT WHEEL AND REAR WHEEL
REMOVING THE REAR WHEEL
5
Order
Part name
Q'ty
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
1
Nut (rear wheel axle)
1
2
Rear wheel axle
1
3
Drive chain puller
2
4
Rear wheel
1
5
Collar
2
6
Rear wheel sprocket
1
7
Oil seal
2
8
Circlip
1
9
Bearing
3
10
Brake disc
1
5-2
Remarks
Refer to removal section.
Refer to removal section.
FRONT WHEEL AND REAR WHEEL
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
REMOVING THE REAR WHEEL
1. Remove:
• Wheel "1"
Push the wheel forward and remove
the drive chain "2".
CHECKING THE WHEEL AXLE
1. Measure:
• Wheel axle bends
Out of specification → Replace.
Use the dial gauge "1".
Wheel axle bending limit:
0.5 mm (0.020 in)
The bending value is shown by one
half of the dial gauge reading.
REMOVING THE WHEEL BEARING
1. Remove:
• Bearing "1"
Do not attempt to straighten a bent
axle.
Remove the bearing using a general
bearing puller "2".
CHECKING THE WHEEL
1. Measure:
• Wheel runout
Out of limit → Repair/replace.
Wheel runout limit:
Radial "1": 2.0 mm
(0.08 in)
Lateral "2": 2.0 mm
(0.08 in)
CHECKING THE BRAKE DISC
1. Measure:
• Brake disc deflection (only rear
brake disc)
Use the dial gauge "1".
Out of specification → Inspect
wheel runout.
If wheel runout is in good condition, replace the brake disc.
Brake disc deflection limit:
Rear:
<Limit>: 0.15 mm
(0.006 in)
2. Measure:
• Brake disc thickness "a"
Out of limit → Replace.
2. Inspect:
• Bearing
Rotate inner race with a finger.
Rough spot/seizure → Replace.
Replace the bearings, oil seal and
wheel collar as a set.
Brake disc thickness:
Front:
3.0 mm (0.12 in)
<Limit>: 2.5 mm (0.10
in)
Rear:
4.0 mm (0.16 in)
<Limit>: 3.5 mm (0.14
in)
5-3
INSTALLING THE FRONT WHEEL
1. Install:
• Bearing (left) "1"
• Spacer "2"
• Bearing (right) "3"
• Oil seal "4"
• Apply the lithium soap base grease
on the bearing and oil seal lip when
installing.
• Use a socket that matches the outside diameter of the race of the
bearing.
• Left side of bearing shall be installed first.
• Install the oil seal with its manufacture's marks or numbers facing outward.
Do not strike the inner race of the
bearing. Contact should be made
only with the outer race.
FRONT WHEEL AND REAR WHEEL
2. Install:
• Brake disc "1"
• Bolt (brake disc) "2"
Bolt (brake disc):
12 Nm (1.2 m•kg, 8.7
ft•lb)
6. Install:
• Nut (wheel axle) "1"
Nut (wheel axle):
105 Nm (10.5 m•kg, 75
ft•lb)
Do not strike the inner race of the
bearing. Contact should be made
only with the outer race.
Tighten the bolts in stage, using a
crisscross pattern.
7. Tighten:
• Bolt (axle holder) "1"
3. Install:
• Collar "1"
• Apply the lithium soap base grease
on the oil seal lip.
• Install the collars with their projections "a" facing the wheel.
Bolt (axle holder):
21 Nm (2.1 m•kg, 15
ft•lb)
Before tightening the bolt, fit the
wheel axle to the axle holder by stroking the front fork several times with
the front brake applied.
2. Install:
• Brake disc "1"
• Bolt (brake disc) "2"
Bolt (brake disc):
14 Nm (1.4 m•kg, 10
ft•lb)
Tighten the bolts in stage, using a
crisscross pattern.
4. Install:
• Wheel
Install the brake disc "1" between the
brake pads "2" correctly.
5. Install:
• Wheel axle "1"
Apply the lithium soap base grease
on the wheel axle.
INSTALLING THE REAR WHEEL
1. Install:
• Bearing (right) "1"
• Circlip "2"
• Spacer "3"
• Bearing (left) "4"
• Oil seal "5"
• Apply the lithium soap base grease
on the bearing and oil seal lip when
installing.
• Install the bearing with seal facing
outward.
• Use a socket that matches the outside diameter of the race of the
bearing.
• Right side of bearing shall be installed first.
• Install the oil seal with its manufacture's marks or numbers facing outward.
5-4
3.
•
•
•
•
Install:
Rear wheel sprocket "1"
Bolt (rear wheel sprocket) "2"
Washer (rear wheel sprocket) "3"
Nut (rear wheel sprocket) "4"
Nut (rear wheel sprocket):
42 Nm (4.2 m•kg, 30
ft•lb)
Tighten the nuts in stage, using a
crisscross pattern.
FRONT WHEEL AND REAR WHEEL
4. Install:
• Collar "1"
Apply the lithium soap base grease
on the oil seal lip.
8.
•
•
•
Install:
Right drive chain puller "1"
Washer "2"
Nut (wheel axle) "3"
Temporarily tighten the nut (wheel
axle) at this point.
5. Install:
• Wheel
Install the brake disc "1" between the
brake pads "2" correctly.
9. Adjust:
• Drive chain slack "a"
Drive chain slack:
50–60 mm (2.0–2.4 in)
Refer to "ADJUSTING THE
DRIVE CHAIN SLACK" section in
the CHAPTER 3.
6. Install:
• Drive chain "1"
Push the wheel "2" forward and install
the drive chain.
10. Tighten:
• Nut (wheel axle) "1"
Nut (wheel axle):
135 Nm (13.5 m•kg, 98
ft•lb)
• Locknut "2"
7. Install:
• Left drive chain puller "1"
• Wheel axle "2"
Locknut:
21 Nm (2.1 m•kg, 15
ft•lb)
• Install the left drive chain puller, and
insert the wheel axle from left side.
• Apply the lithium soap base grease
on the wheel axle.
5-5
FRONT BRAKE AND REAR BRAKE
FRONT BRAKE AND REAR BRAKE
REMOVING THE FRONT BRAKE
Order
Part name
Q'ty
Remarks
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
Drain the brake fluid.
Refer to removal section.
1
Brake hose holder (protector)
2
2
Union bolt
2
3
Brake hose
1
4
Pad pin plug
1
Remove when loosening the pad pin.
5
Pad pin
1
Loosen when disassembling the brake caliper.
6
Brake caliper
1
7
Brake lever
1
8
Brake master cylinder bracket
1
9
Brake master cylinder
1
5-6
FRONT BRAKE AND REAR BRAKE
REMOVING THE REAR BRAKE
Order
Part name
Q'ty
Remarks
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
Rear wheel
Refer to "FRONT WHEEL AND REAR
WHEEL" section.
Drain the brake fluid.
Refer to removal section.
1
Brake pedal
1
2
Brake master cylinder
1
3
Brake hose holder
2
4
Union bolt
2
5
Brake hose
1
6
Pad pin plug
1
Remove when loosening the pad pin.
Loosen when disassembling the brake caliper.
7
Pad pin
1
8
Brake caliper
1
5-7
FRONT BRAKE AND REAR BRAKE
DISASSEMBLING THE BRAKE CALIPER
Order
Part name
Q'ty
Remarks
A.
B.
Front
Rear
A
B
1
Pad pin
1
1
2
Brake pad
2
2
3
Pad support
1
1
4
Brake caliper piston
2
1
Refer to removal section.
5
Brake caliper piston dust seal
2
1
Refer to removal section.
6
Brake caliper piston seal
2
1
Refer to removal section.
5-8
FRONT BRAKE AND REAR BRAKE
DISASSEMBLING THE BRAKE MASTER CYLINDER
Order
Part name
Q'ty
Remarks
A.
B.
1
Brake master cylinder cap
1
2
Diaphragm
1
3
Reservoir float
1
4
Push rod (Front)
1
5
Brake master cylinder boot
1
6
Circlip
1
7
Washer
1
8
Push rod (Rear)
1
9
Brake master cylinder kit
1
5-9
Front
Rear
Use a long nose circlip pliers.
FRONT BRAKE AND REAR BRAKE
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
DRAINING THE BRAKE FLUID
1. Remove:
• Brake master cylinder cap "1"
• Protector (rear brake)
Do not remove the diaphragm.
REMOVING THE BRAKE CALIPER
PISTON
1. Remove:
• Brake caliper piston
Use compressed air and proceed
carefully.
Replace the brake caliper piston
seals and brake caliper piston dust
seals whenever a caliper is disassembled.
• Cover piston with rag and use extreme caution when expelling
piston from cylinder.
• Never attempt to pry out piston.
Caliper piston removal steps:
a. Insert a piece of rag into the brake
caliper to lock one brake caliper.
b. Carefully force the piston out of
the brake caliper cylinder with
compressed air.
A. Front
B. Rear
CHECKING THE BRAKE MASTER
CYLINDER
1. Inspect:
• Brake master cylinder inner surface "a"
Wear/scratches → Replace master cylinder assembly.
Stains → Clean.
A. Front
B. Rear
2. Connect the transparent hose "2"
to the bleed screw "1" and place a
suitable container under its end.
Use only new brake fluid.
A. Front
B. Rear
A. Front
B. Rear
3. Loosen the bleed screw and drain
the brake fluid while pulling the lever in or pushing down on the
pedal.
• Do not reuse the drained brake
fluid.
• Brake fluid may erode painted
surfaces or plastic parts. Always
clean up spilled fluid immediately.
REMOVING THE BRAKE CALIPER
PISTON SEAL KIT
1. Remove:
• Brake caliper piston dust seal "1"
• Brake caliper piston seal "2"
Remove the brake caliper piston
seals and brake caliper piston dust
seals by pushing them with a finger.
A. Front
B. Rear
2. Inspect:
• Diaphragm "1"
Crack/damage → Replace.
Never attempt to pry out brake caliper piston seals and brake caliper
piston dust seals.
A. Front
B. Rear
5-10
FRONT BRAKE AND REAR BRAKE
3. Inspect: (front brake only)
• Reservoir float "1"
Damage → Replace.
4. Inspect:
• Brake master cylinder piston "1"
• Brake master cylinder cup "2"
Wear/damage/score marks → Replace brake master cylinder kit.
CHECKING THE BRAKE CALIPER
1. Inspect:
• Brake caliper cylinder inner surface "a"
Wear/score marks → Replace
brake caliper assembly.
CHECKING THE BRAKE HOSE
1. Inspect:
• Brake hose "1"
Crack/damage → Replace.
A. Front
B. Rear
3. Install:
• Brake caliper piston "1"
HANDLING NOTE
• All internal parts should be
cleaned in new brake fluid only.
• Internal parts should be lubricated with brake fluid when installed.
• Replace the brake caliper piston
seals and brake caliper piston
dust seals whenever a caliper is
disassembled.
Apply the brake fluid on the piston
wall.
• Install the piston with its shallow
depressed side "a" facing the
brake caliper.
• Never force to insert.
INSTALLING THE BRAKE
CALIPER PISTON
1. Clean:
• Brake caliper
• Brake caliper piston seal
• Brake caliper piston dust seal
• Brake caliper piston
Clean them with brake fluid.
2. Install:
• Brake caliper piston seal "1"
• Brake caliper piston dust seal "2"
A. Front
B. Rear
2. Inspect:
• Brake caliper piston "1"
Wear/score marks → Replace
brake caliper piston assembly.
Always use new brake caliper piston seals and brake caliper piston
dust seals.
Replace the brake caliper piston
seals and brake caliper piston dust
seals "2" whenever a caliper is disassembled.
• Apply the brake fluid on the brake
caliper piston seal.
• Apply the silicone grease on the
brake caliper piston dust seal.
• Fit the brake caliper piston seals
and brake caliper piston dust seals
onto the slot on brake caliper correctly.
5-11
A. Front
B. Rear
INSTALLING THE FRONT BRAKE
CALIPER
1. Install:
• Pad support "1"
• Brake pad "2"
• Pad pin "3"
• Install the brake pads with their projections "a" into the brake caliper recesses "b".
• Temporarily tighten the pad pin at
this point.
FRONT BRAKE AND REAR BRAKE
2. Install:
• Brake caliper "1"
• Bolt (brake caliper) "2"
Bolt (brake caliper):
28 Nm (2.8 m•kg, 20
ft•lb)
3. Tighten:
• Pad pin "3"
Pad pin:
18 Nm (1.8 m•kg, 13
ft•lb)
4. Install:
• Pad pin plug "4"
Pad pin plug:
3 Nm (0.3 m•kg, 2.2
ft•lb)
INSTALLING THE REAR BRAKE
CALIPER
1. Install:
• Pad support "1"
• Brake pad "2"
• Pad pin "3"
• Install the brake pads with their projections "a" into the brake caliper recesses "b".
• Temporarily tighten the pad pin at
this point.
3. Install:
• Brake caliper "1"
• Rear wheel "2"
Refer to "FRONT WHEEL AND
REAR WHEEL" section.
4. Tighten:
• Pad pin "3"
Pad pin:
18 Nm (1.8 m•kg, 13
ft•lb)
5. Install:
• Pad pin plug "4"
Pad pin plug:
3 Nm (0.3 m•kg, 2.2
ft•lb)
INSTALLING THE BRAKE
MASTER CYLINDER KIT
1. Clean:
• Brake master cylinder
• Brake master cylinder kit
Clean them with brake fluid.
2. Install:
• Brake master cylinder cup (primary) "1"
• Brake master cylinder cup (secondary) "2"
To brake master cylinder piston
"3".
3. Install:
• Spring "1"
To brake master cylinder piston
"2".
Install the spring at the smaller dia.
side.
4.
•
•
•
•
•
•
Install:
Brake master cylinder kit "1"
Washer (front brake) "2"
Push rod (rear brake) "2"
Circlip "3"
Brake master cylinder boot "4"
Push rod (front brake) "5"
To brake master cylinder.
• Apply the brake fluid on the brake
master cylinder kit.
• Apply the silicone grease on the tip
of the push rod.
• When installing the circlip, use a
long nose circlip pliers.
Apply the brake fluid on the brake
master cylinder cup.
After installing, cylinder cup
should be installed as shown direction. Wrong installation cause
improper brake performance.
2. Install:
• Brake disc cover "1"
• Bolt (brake disc cover) "2"
Bolt (brake disc cover):
10 Nm (1.0 m•kg, 7.2
ft•lb)
A. Front
B. Rear
5-12
FRONT BRAKE AND REAR BRAKE
INSTALLING THE FRONT BRAKE
MASTER CYLINDER
1. Install:
• Brake master cylinder "1"
• Brake master cylinder bracket "2"
• Bolt (brake master cylinder bracket) "3"
Bolt (brake master cylinder bracket):
9 Nm (0.9 m•kg, 6.5
ft•lb)
INSTALLING THE REAR BRAKE
MASTER CYLINDER
1. Install:
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Always use new copper washers.
• Install the bracket so that the arrow
mark "a" face upward.
• First tighten the bolts on the upper
side of the brake master cylinder
bracket, and then tighten the bolts
on the lower side.
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake master cylinder.
2. Install:
• Brake lever "1"
• Bolt (brake lever) "2"
Nut (brake lever):
6 Nm (0.6 m•kg, 4.3
ft•lb)
Apply the silicone grease on the
brake lever sliding surface, bolt and
tip of the push rod.
Install:
Spring "1"
Brake pedal "2"
O-ring "3"
Bolt (brake pedal) "4"
Bolt (brake pedal):
26 Nm (2.6 m•kg, 19
ft•lb)
• Clip "5"
Apply the lithium soap base grease
on the bolt, O-ring and brake pedal
bracket.
4.
•
•
•
Install:
Pin "1"
Washer "2"
Cotter pin "3"
After installing, check the brake pedal
height. Refer to "ADJUSTING THE
REAR BRAKE" section in the CHAPTER 3.
Bolt (brake lever):
6 Nm (0.6 m•kg, 4.3
ft•lb)
• Nut (brake lever) "3"
3.
•
•
•
•
2. Install:
• Brake master cylinder "1"
• Bolt (brake master cylinder) "2"
Bolt (brake master cylinder):
10 Nm (1.0 m•kg, 7.2
ft•lb)
INSTALLING THE FRONT BRAKE
HOSE
1. Install:
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Always use new copper washers.
5-13
FRONT BRAKE AND REAR BRAKE
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake caliper.
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake master cylinder.
2. Install:
• Brake hose holder "1"
• Bolt (brake hose holder) "2"
INSTALLING THE REAR BRAKE
HOSE
1. Install:
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Bolt (brake hose holder):
8 Nm (0.8 m•kg, 5.8 ft
•lb)
Align the top "a" of the brake hose
holder with the paint "b" of the brake
hose.
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Always use new copper washers.
After installing the brake hose
holders, make sure the brake hose
does not contact the spring (rear
shock absorber). If it does, correct
its twist.
FILLING THE BRAKE FLUID
1. Fill:
• Brake fluid
Until the fluid level reaches
"LOWER" level line "a".
Recommended brake fluid:
DOT #4
3. Pass the brake hose through the
cable guide "1".
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake caliper.
4.
•
•
•
Install:
Copper washer "1"
Brake hose "2"
Union bolt "3"
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Always use new copper washers.
2. Install:
• Brake hose holder "1"
• Screw (brake hose holder) "2"
Screw (brake hose holder):
3 Nm (0.3 m•kg, 2.2
ft•lb)
5-14
• Use only the designated quality
brake fluid:
otherwise, the rubber seals may
deteriorate, causing leakage and
poor brake performance.
• Refill with the same type of brake
fluid;
mixing fluids may result in a
harmful chemical reaction and
lead to poor performance.
• Be careful that water does not
enter the master cylinder when
refilling. Water will significantly
lower the boiling point of the fluid and may result in vapor lock.
Brake fluid may erode painted surfaces or plastic parts. Always
clean up spilled fluid immediately.
FRONT BRAKE AND REAR BRAKE
5. Install: (rear brake only)
• Protector "1"
• Bolt (protector) "2"
Bolt (protector):
7 Nm (0.7 m•kg, 5.1
ft•lb)
2.
•
3.
•
4.
•
•
•
•
A. Front
B. Rear
Air bleed:
Brake system
Refer to "BLEEDING THE HYDRAULIC BRAKE SYSTEM" section in the CHAPTER 3.
Inspect:
Brake fluid level
Fluid at lower level → Fill up.
Refer to "CHECKING THE
BRAKE FLUID LEVEL" section in
the CHAPTER 3.
Install:
Reservoir float (front brake)
Diaphragm
Brake master cylinder cap "1"
Screw (brake master cylinder
cap) "2"
Screw (bolt) {brake master cylinder cap}:
2 Nm (0.2 m•kg, 1.4
ft•lb)
After installation, while pulling the
brake lever in or pushing down on
the brake pedal, check whether
there is any brake fluid leaking
where the union bolts are installed
respectively at the brake master
cylinder and brake caliper.
A. Front
B. Rear
5-15
FRONT FORK
FRONT FORK
REMOVING THE FRONT FORK
Order
Part name
Q'ty
Remarks
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
Front wheel
Refer to "FRONT WHEEL AND REAR
WHEEL" section.
Front brake caliper
Refer to "FRONT BRAKE AND REAR
BRAKE" section.
Number plate
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section in the CHAPTER 4.
1
Protector
1
2
Pinch bolt (upper bracket)
2
Only loosening.
3
Damper assembly
1
Loosen when disassembling the front fork.
Refer to removal section.
4
Pinch bolt (lower bracket)
2
Only loosening.
5
Front fork
1
5-16
FRONT FORK
DISASSEMBLING THE FRONT FORK
30 Nm (3.0 m kg, 22 ft lb)
29 Nm (2.9 m kg, 21 ft lb)
1 Nm (0.1 m kg, 0.7 ft lb)
29 Nm (2.9 m kg, 21 ft lb)
55 Nm (5.5 m kg, 40 ft lb)
Order
Part name
Q'ty
Remarks
1
Adjuster
1
Drain the fork oil. Refer to removal section.
2
Fork spring
1
3
Dust seal
1
Refer to removal section.
4
Stopper ring
1
Refer to removal section.
5
Inner tube
1
Refer to removal section.
6
Outer tube
1
7
Piston metal
1
8
Slide metal
1
9
Oil seal washer
1
10
Oil seal
1
11
Base valve
1
Drain the fork oil. Refer to removal section.
12
Damper assembly
1
Drain the fork oil. Refer to removal section.
5-17
FRONT FORK
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
REMOVING THE ADJUSTER
1. Drain the outer tube of its front
fork oil at its top.
2. Loosen:
• Adjuster "1"
The front fork requires careful attention. So it is recommended that the
front fork be maintained at the dealers.
To prevent an accidental explosion
of air, the following instructions
should be observed:
• The front fork with a built-in piston rod has a very sophisticated
internal construction and is particularly sensitive to foreign material. Use enough care not to
allow any foreign material to
come in when the oil is replaced
or when the front fork is disassembled and reassembled.
• Before removing the base valves
or front forks, be sure to extract
the air from the air chamber completely.
REMOVING THE DAMPER
ASSEMBLY
1. Loosen:
• Damper assembly "1"
Oil seal removal steps:
a. Push in slowly "a" the inner tube
just before it bottoms out and then
pull it back quickly "b".
b. Repeat this step until the inner
tube can be pulled out from the
outer tube.
3. Remove:
• Adjuster "1"
• While compressing the inner tube
"2", set the cap bolt ring wrench "4"
between the inner tube and locknut
"3".
• Hold the locknut and remove the
adjuster.
Do not remove the locknut as the
damper rod may go into the damper assembly and not be taken out.
Cap bolt ring wrench:
YM-01501/90890-01501
Before removing the front fork from
the machine, loosen the damper assembly with the cap bolt ring wrench
"2".
Cap bolt ring wrench:
YM-01501/90890-01501
2. Remove:
• Inner tube "1"
REMOVING THE INNER TUBE
1. Remove:
• Dust seal "1"
• Stopper ring "2"
Using slotted-head screwdriver.
Take care not to scratch the inner
tube.
5-18
REMOVING THE BASE VALVE
1. Remove:
• Base valve "1"
From damper assembly "2".
Hold the damper assembly with the
cap bolt ring wrench "3" and use the
cap bolt wrench "4" to remove the
base valve.
Cap bolt wrench:
YM-01500/90890-01500
Cap bolt ring wrench:
YM-01501/90890-01501
FRONT FORK
CHECKING THE DAMPER
ASSEMBLY
1. Inspect:
• Damper assembly "1"
Bend/damage → Replace.
• O-ring "2"
Wear/damage → Replace.
The front fork with a built-in piston
rod has a very sophisticated internal construction and is particularly
sensitive to foreign material.
Use enough care not to allow any
foreign material to come in when
the oil is replaced or when the
front fork is disassembled and reassembled.
CHECKING THE BASE VALVE
1. Inspect:
• Base valve "1"
Wear/damage → Replace.
Contamination → Clean.
• O-ring "2"
Wear/damage → Replace.
• Piston metal "3"
Wear/damage → Replace.
• Spring "4"
Damage/fatigue → Replace base
valve.
• Air bleed screw "5"
Wear/damage → Replace.
CHECKING THE COLLAR
1. Inspect:
• Piston metal "1"
Wear/damage → Replace.
CHECKING THE FORK SPRING
1. Measure:
• Fork spring free length "a"
Out of specification → Replace.
Fork spring free length:
454 mm (17.9 in)
<Limit>: 449 mm (17.7
in)
CHECKING THE INNER TUBE
1. Inspect:
• Inner tube surface "a"
Score marks → Repair or replace.
Use #1,000 grit wet sandpaper.
Damaged oil lock piece → Replace.
• Inner tube bends
Out of specification → Replace.
Use the dial gauge "1".
Inner tube bending limit:
0.2 mm (0.008 in)
The bending value is shown by one
half of the dial gauge reading.
CHECKING THE ADJUSTER
1. Inspect:
• Adjuster "1"
• O-ring "2"
Wear/damage → Replace.
ASSEMBLING THE FRONT FORK
1. Wash the all parts in a clean solvent.
2. Stretch the damper assembly fully.
3. Fill:
• Front fork oil "1"
To damper assembly.
Recommended oil:
Suspension oil "S1"
Oil capacity:
199 cm3 (7.00 Imp oz,
6.73 US oz)
• Be sure to use recommended
fork oil. If other oils are used,
they may have an excessively adverse effect on the front fork performance.
• Never allow foreign materials to
enter the front fork.
Do not attempt to straighten a bent
inner tube as this may dangerously weaken the tube.
CHECKING THE OUTER TUBE
1. Inspect:
• Outer tube "1"
Score marks/wear/damage → Replace.
5-19
4. After filling, pump the damper assembly "1" slowly up and down
(about 200 mm (7.9 in) stroke)
several times to bleed the damper
assembly of air.
Be careful not to excessive full stroke.
A stroke of 200 mm (7.9 in) or more
will cause air to enter. In this case, repeat the steps 2 to 4.
FRONT FORK
5. Measure:
• Oil level (left and right) "a"
Out of specification → Adjust.
Standard oil level:
145-148 mm (5.71-5.83
in)
From top of fully
stretched damper assembly.
8. Install:
• Base valve "1"
To damper assembly "2".
First bring the damper rod pressure to
a maximum. Then install the base
valve while releasing the damper rod
pressure.
9. Check:
• Damper assembly
Not fully stretched → Repeat the
steps 2 to 8.
10. Tighten:
• Base valve "1"
6. Tighten:
• Locknut "1"
Fully finger tighten the locknut onto
the damper assembly.
Take care not to damage the damper assembly.
13. Allow the overflowing oil to escape at the hole "a" in the damper
assembly.
Base valve:
29 Nm (2.9 m•kg, 21 ft•
lb)
Hold the damper assembly with the
cap bolt ring wrench "2" and use the
cap bolt wrench "3" to tighten the
base valve with specified torque.
Cap bolt wrench:
YM-01500/90890-01500
Cap bolt ring wrench:
YM-01501/90890-01501
7. Loosen:
• Compression damping adjuster
"1"
• Loosen the compression damping
adjuster finger tight.
• Record the set position of the adjuster (the amount of turning out the
fully turned in position).
12. While protecting the damper assembly "1" with a rag and compressing fully, allow excessive oil
to overflow on the base valve
side.
11. After filling, pump the damper assembly "1" slowly up and down
more than 10 times to distribute
the fork oil.
14. Check:
• Damper assembly smooth movement
Tightness/binding/rough spots →
Repeat the steps 2 to 13.
15. Install:
• Dust seal "1"
• Stopper ring "2"
• Oil seal "3"
• Oil seal washer "4"
• Slide metal "5"
To inner tube "6".
• Apply the fork oil on the inner tube.
• When installing the oil seal, use vinyl seat "a" with fork oil applied to
protect the oil seal lip.
• Install the oil seal with its manufacture's marks or number facing the
axle holder side.
5-20
FRONT FORK
19. Install:
• Oil seal "1"
Press the oil seal into the outer tube
with fork seal driver "2".
16. Install:
• Piston metal "1"
Fork seal driver:
YM-A0948/90890-01502
23. Measure:
• Distance "a"
Out of specification → Turn into
the locknut.
Distance "a":
16 mm (0.63 in) or more
Between the damper
assembly "1" bottom
and locknut "2" bottom.
Install the piston metal onto the slot
on inner tube.
20. Install:
• Stopper ring "1"
17. Install:
• Outer tube "1"
To inner tube "2".
18. Install:
• Slide metal "1"
• Oil seal washer "2"
To outer tube slot.
Fit the stopper ring correctly in the
groove in the outer tube.
24. Install:
• Collar "1"
• Fork spring "2"
To damper assembly "3".
Install the collar with its larger dia.
end "a" facing the fork spring.
21. Install:
• Dust seal "1"
Apply the lithium soap base grease
on the inner tube.
Press the slide metal into the outer
tube with fork seal driver "3".
Fork seal driver:
YM-A0948/90890-01502
22. Check:
• Inner tube smooth movement
Tightness/binding/rough spots →
Repeat the steps 15 to 21.
5-21
25. Install:
• Damper assembly "1"
To inner tube "2".
To install the damper assembly
into the inner tube, hold the inner
tube aslant. If the inner tube is held
vertically, the damper assembly
may fall into it, damaging the valve
inside.
FRONT FORK
26. Loosen:
• Rebound damping adjuster "1"
• Loosen the rebound damping adjuster finger tight.
• Record the set position of the adjuster (the amount of turning out the
fully turned in position).
29. Tighten:
• Adjuster (locknut) "1"
Adjuster (locknut):
29 Nm (2.9 m•kg, 21
ft•lb)
27. Install:
• Push rod "1"
• Copper washer "2"
• Adjuster "3"
To damper assembly "4".
• While compressing the inner tube
"5", set the cap bolt ring wrench "7"
between the inner tube and locknut
"6".
• Fully finger tighten the adjuster onto
the damper assembly.
Cap bolt ring wrench:
YM-01501/90890-01501
28. Inspect:
• Gap "a" between the adjuster "1"
and locknut "2".
Out of specification → Retighten
and readjust the locknut.
Gap "a" between the adjuster and locknut:
0.5–1.0 mm (0.02–0.04
in)
If the adjuster is installed out of specification, proper damping force cannot be obtained.
Hold the locknut "2" and tighten the
adjuster with specified torque.
30. Install:
• Adjuster "1"
Adjuster:
55 Nm (5.5 m•kg, 40
ft•lb)
To inner tube.
31. Fill:
• Front fork oil "1"
From outer tube top.
Recommended oil:
Suspension oil "S1"
Standard oil amount:
350 cm3 (12.3 Imp oz,
11.8 US oz)
*337 cm3 (11.9 Imp oz,
11.4 US oz)
Extent of adjustment:
300–375 cm3
(10.6–13.2 Imp
oz,10.1–12.7 US oz)
* Except for USA & CDN
5-22
Never fail to make the oil amount
adjustment between the maximum
and minimum amount and always
adjust each front fork to the same
setting. Uneven adjustment can
cause poor handling and loss of
stability.
• Be sure to use recommended
fork oil. If other oils are used,
they may have an excessively adverse effect on the front fork performance.
• Never allow foreign materials to
enter the front fork.
32. Install:
• Damper assembly "1"
To outer tube.
Temporarily tighten the damper assembly.
33. Install:
• Protector guide "1"
FRONT FORK
INSTALLING THE FRONT FORK
1. Install:
• Front fork "1"
• Temporarily tighten the pinch bolts
(lower bracket).
• Do not tighten the pinch bolts (upper bracket) yet.
4. Tighten:
• Pinch bolt (upper bracket) "1"
Pinch bolt (upper bracket):
21 Nm (2.1 m•kg, 15
ft•lb)
• Pinch bolt (lower bracket) "2"
Pinch bolt (lower bracket):
21 Nm (2.1 m•kg, 15
ft•lb)
2. Tighten:
• Damper assembly "1"
Tighten the lower bracket to specified torque. If torqued too much, it
may cause the front fork to malfunction.
Damper assembly:
30 Nm (3.0 m•kg, 22
ft•lb)
Use the cap bolt ring wrench "2" to
tighten the damper assembly with
specified torque.
Cap bolt ring wrench:
YM-01501/90890-01501
5. Install:
• Protector "1"
• Bolt (protector) "2"
Bolt (protector):
5 Nm (0.5 m•kg, 3.6
ft•lb)
3. Adjust:
• Front fork top end "a"
Front fork top end (standard) "a":
5 mm (0.20 in)
6. Adjust:
• Rebound damping force
Turn in the damping adjuster "1" finger-tight and then turn out to the originally set position.
5-23
7. Adjust:
• Compression damping force
Turn in the damping adjuster "1" finger-tight and then turn out to the originally set position.
HANDLEBAR
HANDLEBAR
REMOVING THE HANDLEBAR
Order
Part name
Q'ty
Number plate
Remarks
Remove the band only.
1
Hot starter cable
1
2
Hot starter lever holder
1
3
Clutch cable
1
4
Clutch lever holder
1
Disconnect at the lever side.
Disconnect at the lever side.
5
Engine stop switch
1
6
Brake master cylinder
1
7
Throttle cable cap
1
8
Throttle cable #1 (pulled)
1
Disconnect at the throttle side.
Refer to removal section.
9
Throttle cable #2 (pushed)
1
Disconnect at the throttle side.
10
Right grip
1
Refer to removal section.
11
Tube guide
1
12
Collar
1
13
Left grip
1
14
Handlebar upper holder
2
15
Handlebar
1
16
Handlebar lower holder
2
5-24
Refer to removal section.
HANDLEBAR
REMOVING THE BRAKE MASTER
CYLINDER
1. Remove:
• Brake master cylinder bracket "1"
• Brake master cylinder "2"
• Do not let the brake master cylinder hang on the brake hose.
• Keep the brake master cylinder
cap side horizontal to prevent air
from coming in.
REMOVING THE GRIP
1. Remove:
• Grip "1"
INSTALLING THE HANDLEBAR
1. Install:
• Handlebar lower holder "1"
• Washer "2"
• Nut (handlebar lower holder) "3"
• Be sure the side of the handlebar
lower holder having the greater distance "a" from the mounting bolt
center faces forward. And install it
in the hole "b" in the rear of the upper bracket.
• Apply the lithium soap base grease
on the thread of the handlebar lower holder.
• Change in the direction back to
front and installing position of the
handlebar lower holder allows the
front-to-rear offset amount of the
handlebar position to be changed.
• Do not tighten the nut yet.
Blow in air between the handlebar or
tube guide and the grip. Then remove
the grip which has become loose.
CHECKING THE HANDLEBAR
1. Inspect:
• Handlebar "1"
Bends/cracks/damage → Replace.
Do not attempt to straighten a bent
handlebar as this may dangerously weaken the handlebar.
2.
•
•
•
A. Forward
Install:
Handlebar "1"
Handlebar upper holder "2"
Bolt (handlebar upper holder) "3"
Bolt (handlebar upper
holder):
28 Nm (2.8 m•kg, 20
ft•lb)
5-25
• The handlebar upper holder should
be installed with the punched mark
"a" forward.
• Install the handlebar so that the
marks "b" are in place on both
sides.
• Install the handlebar so that the projection "c" of the handlebar upper
holder is positioned at the mark on
the handlebar as shown.
• First tighten the bolts on the front
side of the handlebar upper holder,
and then tighten the bolts on the
rear side.
HANDLEBAR
3. Tighten:
• Nut (handlebar lower holder) "1"
Nut (handlebar lower
holder):
34 Nm (3.4 m•kg, 24
ft•lb)
6.
•
•
•
4. Install:
• Left grip "1"
Apply the adhesive to the handlebar "2".
• Before applying the adhesive, wipe
off grease or oil on the handlebar
surface "a" with a lacquer thinner.
• Install the left grip to the handlebar
so that the line "b" between the two
arrow marks faces straight upward.
Install:
Collar "1"
Grip cap cover "2"
Throttle grip "3"
Apply the lithium soap base grease
on the throttle grip sliding surface.
7. Install:
• Throttle cables "1"
To tube guide "2".
Apply the lithium soap base grease
on the throttle cable end and tube
guide cable winding portion.
5. Install:
• Right grip "1"
• Collar "2"
Apply the adhesive on the tube
guide "3".
• Before applying the adhesive, wipe
off grease or oil on the tube guide
surface "a" with a lacquer thinner.
• Install the grip to the tube guide so
that the grip match mark "b" and
tube guide slot "c" form the angle as
shown.
9. Install:
• Grip cap cover "1"
• Cover (throttle cable cap) "2"
10. Install:
• Brake master cylinder "1"
• Brake master cylinder bracket "2"
• Bolt (brake master cylinder bracket) "3"
Bolt (brake master cylinder bracket):
9 Nm (0.9 m•kg, 6.5
ft•lb)
• Install the bracket so that the arrow
mark "a" faces upward.
• First tighten the bolt on the upper
side of the brake master cylinder
bracket, and then tighten the bolt on
the lower side.
8. Install:
• Throttle cable cap "1"
• Screw (throttle cable cap) "2"
Screw (throttle cable
cap):
4 Nm (0.4 m•kg, 2.9
ft•lb)
After tightening the screws, check
that the throttle grip "3" moves
smoothly. If it does not, retighten
the bolts for adjustment.
11. Install:
• Engine stop switch "1"
• Clutch lever holder "2"
• Bolt (clutch lever holder) "3"
Bolt (clutch lever holder):
5 Nm (0.5 m•kg, 3.6
ft•lb)
• Hot starter lever holder "4"
• Bolt (hot starter lever holder) "5"
Bolt (hot starter lever
holder):
4 Nm (0.4 m•kg, 2.9
ft•lb)
5-26
HANDLEBAR
• Clamp "6"
• The engine stop switch, clutch lever
holder and clamp should be installed according to the dimensions
shown.
• Pass the engine stop switch lead in
the middle of the clutch lever holder.
12. Install:
• Clutch cable "1"
• Hot starter cable "2"
Apply the lithium soap base grease
on the clutch cable end and hot starter cable end.
13. Adjust:
• Clutch lever free play
Refer to "ADJUSTING THE
CLUTCH CABLE FREE PLAY"
section in the CHAPTER 3.
• Hot starter lever free play
Refer to "ADJUSTING THE HOT
STARTER LEVER FREE PLAY"
section in the CHAPTER 3.
5-27
STEERING
STEERING
REMOVING THE STEERING
Order
Part name
Q'ty
Remarks
TIGHTENING STEPS:
• Tighten ring nut. 38 Nm (3.8 m•kg, 27 ft•lb)
• Loosen it one turn.
• Retighten it. 7 Nm (0.7 m•kg, 5.1 ft•lb)
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
Number plate
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section in the CHAPTER 4.
Handlebar
Refer to "HANDLEBAR" section.
1
Front fender
1
2
Steering stem nut
1
3
Front fork
2
4
Upper bracket
1
5
Steering ring nut
1
6
Lower bracket
1
7
Bearing race cover
1
8
Upper bearing
1
9
Lower bearing
1
Refer to removal section.
10
Bearing race
2
Refer to removal section.
5-28
Refer to "FRONT FORK" section.
Refer to removal section.
STEERING
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
CHECKING THE STEERING STEM
1. Inspect:
• Steering stem "1"
Bend/damage → Replace.
Support the steering stem so that
it may not fall down.
REMOVING THE LOWER
BEARING
1. Remove:
• Lower bearing "1"
Use the floor chisel "2".
Install:
Bearing race
Upper bearing "1"
Bearing race cover "2"
Apply the lithium soap base grease
on the bearing and bearing race cover lip.
REMOVING THE STEERING RING
NUT
1. Remove:
• Steering ring nut "1"
Use the steering nut wrench "2".
Steering nut wrench:
YU-33975/90890-01403
2.
•
•
•
CHECKING THE BEARING AND
BEARING RACE
1. Wash the bearings and bearing
races with a solvent.
2. Inspect:
• Bearing "1"
• Bearing race
Pitting/damage → Replace bearings and bearing races as a set.
Install the bearing in the bearing
races. Spin the bearings by hand.
If the bearings hang up or are not
smooth in their operation in the
bearing races, replace bearings
and bearing races as a set.
3. Install:
• Lower bracket "1"
Apply the lithium soap base grease
on the bearing, the portion "a" and
thread of the steering stem.
4. Install:
• Steering ring nut "1"
Take care not to damage the steering shaft thread.
INSTALLING THE LOWER
BRACKET
1. Install:
• Lower bearing "1"
Apply the lithium soap base grease
on the dust seal lip and bearing inner
circumference.
REMOVING THE BEARING RACE
1. Remove:
• Bearing race "1"
Remove the bearing race using
long rod "2" and the hammer.
5-29
Steering ring nut:
7 Nm (0.7 m•kg, 5.1 ft•
lb)
Install the steering nut with its
stepped side "a" facing downward.
Tighten the steering ring nut using
the steering nut wrench "2".
Refer to "CHECKING AND ADJUSTING THE STEERING
HEAD" section in the CHAPTER
3.
STEERING
5. Check the steering stem by turning it lock to lock. If there is any
binding, remove the steering stem
assembly and inspect the steering bearings.
9. After tightening the nut, check the
steering for smooth movement. If
not, adjust the steering by loosening the steering ring nut little by little.
10. Adjust:
• Front fork top end "a"
Front fork top end (standard) "a":
5 mm (0.20 in)
6. Install:
• Washer "1"
11. Tighten:
• Pinch bolt (upper bracket) "1"
7. Install:
• Front fork "1"
• Upper bracket "2"
• Temporarily tighten the pinch bolts
(lower bracket).
• Do not tighten the pinch bolts (upper bracket) yet.
Pinch bolt (upper bracket):
21 Nm (2.1 m•kg, 15
ft•lb)
• Pinch bolt (lower bracket) "2"
Pinch bolt (lower bracket):
21 Nm (2.1 m•kg, 15
ft•lb)
Tighten the lower bracket to specified torque. If torqued too much, it
may cause the front fork to malfunction.
8. Install:
• Steering stem nut "1"
Steering stem nut:
145 Nm (14.5 m•kg, 105
ft•lb)
Apply the lithium soap base grease
on the contact surface of the steering
stem nut when installing.
5-30
SWINGARM
SWINGARM
REMOVING THE SWINGARM
Order
Part name
Q'ty
Remarks
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
Brake hose holder
Refer to "FRONT BRAKE AND REAR
BRAKE" section.
Rear brake caliper
Refer to "FRONT BRAKE AND REAR
BRAKE" section.
Bolt (brake pedal)
Shift the brake pedal backward.
Drive chain
1
Drive chain support
1
2
Lower chain tensioner
1
3
Bolt (rear shock absorber-relay arm)
1
4
Bolt (connecting rod)
1
5
Pivot shaft
1
6
Swingarm
1
5-31
Hold the swingarm.
SWINGARM
DISASSEMBLING THE SWINGARM
Order
Part name
Q'ty
1
Relay arm
1
2
Connecting rod
1
3
Collar
2
4
Oil seal
2
5
Thrust bearing
2
6
Bushing
2
7
Oil seal
8
8
Bearing
10
5-32
Remarks
Refer to removal section.
SWINGARM
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
REMOVING THE BEARING
1. Remove:
• Bearing "1"
Remove the bearing by pressing its
outer race.
CHECKING THE CONNECTING
ROD
1. Inspect:
• Bearing "1"
• Collar "2"
Free play exists/unsmooth revolution/rust → Replace bearing and
collar as a set.
2. Inspect:
• Oil seal "3"
Damage → Replace.
2.
•
•
•
Install:
Bearing "1"
Washer "2"
Oil seal "3"
To relay arm.
• Apply the molybdenum disulfide
grease on the bearing when installing.
• Install the bearing by pressing it on
the side having the manufacture's
marks or numbers.
• Apply the molybdenum disulfide
grease on the washer.
Installed depth of bearings "a":
Zero mm (Zero in)
CHECKING THE SWINGARM
1. Inspect:
• Bearing "1"
• Bushing "2"
Free play exists/unsmooth revolution/rust → Replace bearing and
bushing as a set.
2. Inspect:
• Oil seal "3"
Damage → Replace.
CHECKING THE RELAY ARM
1. 5294Inspect:
• Bearing "1"
• Collar "2"
Free play exists/unsmooth revolution/rust → Replace bearing and
collar as a set.
2. Inspect:
• Oil seal "3"
Damage → Replace.
INSTALLING THE BEARING AND
OIL SEAL
1. Install:
• Bearing "1"
• Oil seal "2"
To swingarm.
• Apply the molybdenum disulfide
grease on the bearing when installing.
• Install the bearing by pressing it on
the side having the manufacture's
marks or numbers.
• First install the outer and then the
inner bearings to a specified depth
from inside.
Installed depth of bearings:
Outer "a": Zero mm
(Zero in)
Inner "b": 6.5 mm (0.26
in)
3. Install:
• Bearing "1"
• Oil seal "2"
To connecting rod.
• Apply the molybdenum disulfide
grease on the bearing when installing.
• Install the bearing by pressing it on
the side having the manufacture's
marks or numbers.
Installed depth of bearings "a":
Zero mm (Zero in)
5-33
SWINGARM
INSTALLING THE SWINGARM
1. Install:
• Bushing "1"
• Thrust bearing "2"
• Oil seal "3"
• Collar "4"
To swingarm "5".
Apply the molybdenum disulfide
grease on the bushings, thrust bearings, oil seal lips and contact surfaces
of the collar and thrust bearing.
2. Install:
• Collar "1"
• Washer "2"
To relay arm "3".
Apply the molybdenum disulfide
grease on the bolt.
5.
•
•
•
•
Install:
Relay arm "1"
Bolt (relay arm) "2"
Washer "3"
Nut (relay arm) "4"
To swingarm.
• Apply the molybdenum disulfide
grease on the bolt.
• Do not tighten the nut yet.
9. Install:
• Bolt (rear shock absorber-relay
arm) "1"
• Nut (rear shock absorber-relay
arm) "2"
6. Install:
• Swingarm "1"
• Pivot shaft "2"
Apply the molybdenum disulfide
grease on the collar and oil seal lips.
Install:
Bolt (connecting rod) "1"
Washer "2"
Nut (connecting rod) "3"
• Apply the molybdenum disulfide
grease on the bolt circumference
and threaded portion.
• Do not tighten the nut yet.
Apply the molybdenum disulfide
grease on the collars and oil seal lips.
3. Install:
• Collar "1"
To connecting rod "2".
8.
•
•
•
Pivot shaft:
85 Nm (8.5 m•kg, 61
ft•lb)
Nut (rear shock absorber-relay arm):
53 Nm (5.3 m•kg, 38
ft•lb)
Apply the molybdenum disulfide
grease on the bolt.
• Apply the molybdenum disulfide
grease on the pivot shaft.
• Insert the pivot shaft from right side.
10. Tighten:
• Nut (connecting rod) "1"
4.
•
•
•
•
Install:
Connecting rod "1"
Bolt (connecting rod) "2"
Washer "3"
Nut (connecting rod) "4"
Nut (connecting rod):
80 Nm (8.0 m•kg, 58
ft•lb)
7. Check:
• Swingarm side play "a"
Free play exists → Replace thrust
bearing.
• Swingarm up and down movement "b"
Unsmooth movement/binding/
rough spots → Grease or replace
bearings, bushings and collars.
To relay arm "5".
5-34
Nut (connecting rod):
80 Nm (8.0 m•kg, 58
ft•lb)
SWINGARM
11. Tighten:
• Nut (relay arm) "1"
Nut (relay arm):
70 Nm (7.0 m•kg, 50
ft•lb)
12. Install:
• Bolt (lower chain tensioner) "1"
• Washer "2"
• Collar "3"
• Lower chain tensioner "4"
• Nut (lower chain tensioner) "5"
Nut (lower chain tensioner):
16 Nm (1.6 m•kg, 11
ft•lb)
13. Install:
• Drive chain support "1"
• Drive chain support cover "2"
• Bolt {drive chain support [L = 50
mm (1.97 in)]} "3"
• Nut (drive chain support) "4"
Nut (drive chain support):
7 Nm (0.7 m•kg, 5.1
ft•lb)
• Bolt {drive chain support cover [L
= 10 mm (0.39 in)]} "5"
Bolt (drive chain support
cover):
7 Nm (0.7 m•kg, 5.1
ft•lb)
5-35
REAR SHOCK ABSORBER
REAR SHOCK ABSORBER
REMOVING THE REAR SHOCK ABSORBER
11
2
B
10
9
8
11
Order
Part name
Q'ty
Remarks
Hold the machine by placing the suitable stand
under the engine.
Refer to "HANDLING NOTE".
Seat
Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section in the CHAPTER 4.
Silencer
Refer to "EXHAUST PIPE AND SILENCER"
section in the CHAPTER 4.
1
Clamp (air filter joint)
1
2
Rear frame
1
3
Bolt (rear shock absorber-relay arm)
1
Only loosening.
Hold the swingarm.
4
Bolt (rear shock absorber-frame)
1
5
Rear shock absorber
1
6
Locknut
1
Only loosening.
7
Adjuster
1
Only loosening.
8
Lower spring guide
1
9
Upper spring guide
1
10
Spring (rear shock absorber)
1
11
Bearing
2
5-36
Refer to removal section.
REAR SHOCK ABSORBER
HANDLING NOTE
• Support the machine securely so
there is no danger of it falling
over.
• This rear shock absorber is provided with a separate type tank
filled with high-pressure nitrogen gas. To prevent the danger
of explosion, read and understand the following information
before handling the shock absorber. The manufacturer can
not be held responsible for property damage or personal injury
that may result from improper
handling.
• Never tamper or attempt to disassemble the cylinder or the
tank.
• Never throw the rear shock absorber into an open flame or
other high heat. The rear shock
absorber may explode as a result of nitrogen gas expansion
and/ or damage to the hose.
• Be careful not to damage any
part of the gas tank. A damaged
gas tank will impair the damping performance or cause a
malfunction.
• Take care not to scratch the
contact surface of the piston
rod with the cylinder; or oil
could leak out.
• Never attempt to remove the
plug at the bottom of the nitrogen gas tank. It is very dangerous to remove the plug.
• When scrapping the rear shock
absorber, follow the instructions on disposal.
NOTES ON DISPOSAL (YAMAHA
DEALERS ONLY)
Before disposing the rear shock absorber, be sure to extract the nitrogen
gas from valve "1". Wear eye protection to prevent eye damage from escaping gas and/or metal chips.
3. Remove:
• Lower bearing "1"
Remove the bearing by pressing its
outer race.
To dispose of a damaged or wornout rear shock absorber, take the
unit to your Yamaha dealer for this
disposal procedure.
REMOVING THE BEARING
1. Remove:
• Stopper ring (upper bearing) "1"
Press in the bearing while pressing its
outer race and remove the stopper
ring.
2. Remove:
• Upper bearing "1"
Remove the bearing by pressing its
outer race.
5-37
CHECKING THE REAR SHOCK
ABSORBER
1. Inspect:
• Damper rod "1"
Bends/damage → Replace rear
shock absorber assembly.
• Shock absorber "2"
Oil leaks → Replace rear shock
absorber assembly.
Gas leaks → Replace rear shock
absorber assembly.
• Spring "3"
Damage → Replace spring.
Fatigue → Replace spring.
Move spring up and down.
• Spring guide "4"
Wear/damage → Replace spring
guide.
• Bearing "5"
Free play exists/unsmooth revolution/rust → Replace.
REAR SHOCK ABSORBER
INSTALLING THE BEARING
1. Install:
• Upper bearing "1"
Install the bearing parallel until the
stopper ring groove appears by
pressing its outer race.
Do not apply the grease on the
bearing outer race because it will
wear the rear shock absorber surface on which the bearing is press
fitted.
INSTALLING THE SPRING (REAR
SHOCK ABSORBER)
1. Install:
• Spring "1"
• Upper spring guide "2"
• Lower spring guide "3"
2.
•
•
•
Install:
Bushing "1"
Collar "2"
Dust seal "3"
• Apply the molybdenum disulfide
grease on the bearing and dust seal
lips.
• Install the dust seals with their lips
facing inward.
2. Tighten:
• Adjuster "1"
3.
•
4.
•
2. Install:
• Stopper ring (upper bearing) "1"
After installing the stopper ring, push
back the bearing until it contacts the
stopper ring.
3. Adjust:
• Spring length (installed)
Refer to "ADJUSTING THE
REAR SHOCK ABSORBER
SPRING PRELOAD" section in
the CHAPTER 3.
4. Tighten:
• Locknut "1"
Install:
Rear shock absorber
Install:
Bolt (rear shock absorber-frame)
"1"
• Washer "2"
• Nut (rear shock absorber-frame)
"3"
Nut (rear shock absorber-frame):
56 Nm (5.6 m•kg, 40
ft•lb)
Apply the molybdenum disulfide
grease on the bolt.
3. Install:
• Lower bearing "1"
Install the bearing by pressing it on
the side having the manufacture's
marks or numbers.
Installed depth of the
bearing "a":
4 mm (0.16 in)
INSTALLING THE REAR SHOCK
ABSORBER
1. Install:
• Dust seal "1"
• O-ring "2"
• Collar "3"
• Apply the molybdenum disulfide
grease on the dust seal lips and collars.
• Apply the lithium soap base grease
on the O-rings.
5. Install:
• Bolt (rear shock absorber-relay
arm) "1"
• Nut (rear shock absorber-relay
arm) "2"
Nut (rear shock absorber-relay arm):
53 Nm (5.3 m•kg, 38
ft•lb)
Apply the molybdenum disulfide
grease on the bolt.
5-38
REAR SHOCK ABSORBER
6. Install:
• Rear frame "1"
• Bolt [rear frame (upper)] "2"
Bolt [rear frame (upper)]:
32 Nm (3.2 m•kg, 23
ft•lb)
• Bolt [rear frame (lower)] "3"
Bolt [rear frame (lower)]:
32 Nm (3.2 m•kg, 23
ft•lb)
7. Tighten:
• Bolt (air filter joint) "1"
Bolt (air filter joint):
3 Nm (0.3 m•kg, 2.2
ft•lb)
5-39
ELECTRICAL
This section is intended for those who have basic knowledge and skill concerning the servicing of Yamaha motorcycles
(e.g., Yamaha dealers, service engineers, etc.) Those who have little knowledge and skill concerning servicing are requested not to undertake inspection, adjustment, disassembly, or reassembly only by reference to this manual. It may lead to
servicing trouble and mechanical damage.
6
6-1
ELECTRICAL COMPONENTS AND WIRING DIAGRAM
ELECTRICAL
COMPONENTS AND
WIRING DIAGRAM
ELECTRICAL COMPONENTS
1.
2.
3.
Engine stop switch
Throttle position sensor
Neutral switch
4.
5.
6.
7.
CDI magneto
Ignition coil
Spark plug
CDI unit
WIRING DIAGRAM
B/W
B/W G/B
G/B
L
Y
B/L
Y
Sb
Sb
Y
W
L
L
W
G
B/L
B/L
G
P
B/Y
B/Y
P
Br
R
R
Br
B/W
G/B
G/B
B/W
B
O
B
O
Y
B
L
L
B/L
Sb
B/W
B/W
B
Y
B
Sb
L
Y
B
Sb
Sb
P
P
Br
G
W
R
B/Y
O
B
Br
P
Br
W
W
Br
P
B/Y
G
R
R
G
B
G
W
R
B
O
1.
2.
3.
4.
5.
6.
7.
Engine stop switch
Throttle position sensor
Neutral switch
CDI magneto
Ignition coil
Spark plug
CDI unit
COLOR CODE
B
Black
Br
Brown
G
Green
L
Blue
O
Orange
P
Pink
R
Red
Sb
Sky blue
W
White
Y
Yellow
6-2
B/L
B/W
B/Y
G/B
L/W
R/W
B
Black/Blue
Black/White
Black/Yellow
Green/Black
Blue/White
Red/White
IGNITION SYSTEM
IGNITION SYSTEM
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to ignition system failure
and for checking the spark plug which will not spark.
Spark gap test
Spark →
*Clean or replace spark plug.
No spark ↓
Check entire ignition system for connection.
(couplers, leads and ignition coil)
No good →
Repair or replace.
OK ↓
Check engine stop switch.
No good →
Replace.
OK ↓
Check ignition coil. (primary coil and secondary
coil)
No good →
Replace.
OK ↓
Check CDI magneto. (pickup coil and charging
coil)
No good →
Replace.
OK ↓
Check neutral switch.
No good →
OK ↓
Replace CDI unit.
*marked: Only when the ignition checker is used.
• Remove the following parts before inspection.
1. Seat
2. Fuel tank
• Use the following special tools in this inspection.
Dynamic spark tester:
YM-34487
Ignition checker:
90890-06754
Pocket tester:
YU-3112-C/90890-03112
6-3
Repair or replace.
IGNITION SYSTEM
SPARK GAP TEST
1. Disconnect the ignition coil from
spark plug.
2. Remove the ignition coil cap.
3. Connect the dynamic spark tester
"1" (ignition checker "2") as
shown.
• Ignition coil "3"
• Spark plug "4"
CHECKING THE ENGINE STOP
SWITCH
1. Inspect:
• Engine stop switch conduction
Tester (+) lead→Black/White lead
"1"
Tester (-) lead → Black lead "2"
3. Inspect:
• Secondary coil resistance
Out of specification → Replace.
Tester (+) lead → Orange lead "1"
Tester (-) lead → Spark plug terminal "2"
Result
Conductive (while the
engine stop switch is
pushed)
Not conductive while it is pushed →
Replace.
Conductive while it is freed → Replace.
Secondary
coil resistance
Tester selector position
4.6–6.8
kΩat 20 °C
(68 °F)
kΩ × 1
Set the tester selection position to "Ω
× 1".
4.
•
•
•
B B /W
A. For USA and CDN
B. Except for USA and CDN
4. Kick the kickstarter crank.
5. Check the ignition spark gap.
6. Start engine, and increase spark
gap until misfire occurs. (for USA
and CDN only)
Minimum spark gap:
6.0 mm (0.24 in)
CHECKING THE COUPLERS,
LEADS AND IGNITION COIL
CONNECTION
1. Check:
• Couplers and leads connection
Rust/dust/looseness/short-circuit
→ Repair or replace.
• Ignition coil and spark plug as
they are fitted
Push in the ignition coil until it
closely contacts the spark plug
hole in the cylinder head cover.
Inspect:
Sealed portion of ignition coil "a"
Spark plug terminal pin "b"
Threaded portion of spark plug "c"
Wear → Replace.
CHECKING THE IGNITION COIL
1. Remove the ignition coil cap.
2. Inspect:
• Primary coil resistance
Out of specification → Replace.
Tester (+) lead → Orange lead "1"
Tester (-) lead → Black lead "2"
Primary
coil resistance
Tester selector position
0.08–0.10
Ω at 20 °C
(68 °F)
Ω×1
CHECKING THE CDI MAGNETO
1. Inspect:
• Pickup coil resistance
Out of specification → Replace.
Tester (+) lead → Red lead "1"
Tester (-) lead → White lead "2"
Pickup coil
resistance
Tester selector position
248-372 Ω
at 20 °C (68
°F)
Ω ×100
W Br P
R G B
6-4
IGNITION SYSTEM
2. Inspect:
• Charging coil 1 resistance
Out of specification → Replace.
Tester (+) lead → Brown lead "1"
Tester (-) lead → Green lead "2"
Charging
Tester secoil 1 resis- lector positance
tion
720-1,080
Ω at 20 °C
(68 °F)
Ω ×100
W Br P
R G B
CHECKING THE NEUTRAL
SWITCH
1. Inspect:
• Neutral switch conduction
Tester (+) lead→Sky blue lead "1"
Tester (-) lead → Ground "2"
Result
Conductive (while gear
is in neutral)
Not conductive while it is in neutral →
Replace.
Conductive while it is engaged → Replace.
Set the tester selection position to "Ω
× 1".
3. Inspect:
• Charging coil 2 resistance
Out of specification → Replace.
Tester (+) lead → Pink lead "1"
Tester (-) lead → Black lead "2"
Charging
Tester secoil 2 resis- lector positance
tion
44-66 Ω at
20 °C (68
°F)
Ω ×10
CHECKING THE CDI UNIT
Check all electrical components. If no
fault is found, replace the CDI unit.
Then check the electrical components again.
W Br P
R G B
6-5
THROTTLE POSITION SENSOR SYSTEM
THROTTLE POSITION SENSOR SYSTEM
INSPECTION STEPS
If the throttle position sensor will not operate, use the following inspection steps.
Check entire ignition system for connection.
No good →
Repair or replace.
OK ↓
Check throttle position sensor. (Throttle position No good →
sensor coil)
Replace.
OK ↓
*Check CDI magneto. (Charging coil)
No good →
Replace.
OK ↓
Check CDI unit. (Throttle position sensor input
voltage)
No good →
*marked: Refer to "IGNITION SYSTEM" section.
Use the following special tools in this inspection.
Pocket tester:
YU-3112-C/90890-03112
6-6
Replace.
THROTTLE POSITION SENSOR SYSTEM
HANDLING NOTE
Do not loosen the screw (throttle
position sensor) "1" except when
changing the throttle position sensor due to failure because it will
cause a drop in engine performance.
3. Inspect:
• Throttle position sensor coil variable resistance
Check that the resistance in increased as the throttle grip is
moved from the full close position
to the full open position.
Out of specification → Replace.
Tester (+) lead → Yellow lead "1"
Tester (-) lead → Black lead "2"
4. Install:
• Throttle position sensor "1"
• Screw (throttle position sensor)
"2"
• Align the slot "a" in the throttle position sensor with the projection "b"
on the carburetor.
• Temporarily tighten the screw
(throttle position sensor).
TesThrottle position ter sesensor coil vari- lector
able resistance position
CHECKING THE COUPLERS AND
LEADS CONNECTION
1. Check:
• Couplers and leads connection
Rust/dust/looseness/short-circuit
→ Repair or replace.
CHECKING THE THROTTLE
POSITION SENSOR COIL
1. Inspect:
• Throttle position sensor coil resistance
Out of specification → Replace.
Tester (+) lead → Blue lead "1"
Tester (-) lead → Black lead "2"
Throttle poTester sesition senlector posisor coil
tion
resistance
4–6 kΩ at
20°C (68 °F)
kΩ×1
L
Y
B
Full
closed
Full
opened
Zero –3
kΩat
20°C
(68 °F)
4–6
kΩat
20 °C
(68 °F)
L
Y
B
CHANGING AND ADJUSTING THE
THROTTLE POSITION SENSOR
1. Remove:
• Throttle position sensor coupler
• Carburetor
2. Remove:
• Screw (throttle position sensor)
"1"
• Throttle position sensor "2"
Loosen the screw (throttle position
sensor) using the T25 bit.
2. Loosen:
• Throttle stop screw "1"
Turn out the throttle stop screw until
the throttle shaft is in the full close position.
kΩ×1
3. Replace:
• Throttle position sensor
6-7
5.
•
•
6.
•
Install:
Carburetor
Throttle position sensor coupler
Adjust:
Engine idling speed
Refer to "ADJUSTING THE ENGINE IDLING SPEED" section in
the CHAPTER 3.
7. Insert the thin electric conductors
"2" (lead) into the throttle position
sensor coupler "1", as shown, and
connect the tester to them.
Tester (+) lead → Yellow lead "3"
Tester (-) lead → Black lead "4"
• Do not insert the electric conductors more than required because
it may reduce the waterproof
function of the coupler.
• Make sure that a short-circuit
does not develop between the
terminals because it may cause
damage to electrical components.
THROTTLE POSITION SENSOR SYSTEM
8. Start the engine.
9. Adjust:
• Throttle position sensor output
voltage
Adjustment steps:
a. Adjust the installation angle of the
throttle position sensor "1" to obtain the specified output voltage.
Measure the output voltage accurately with a digital electronic voltmeter
that gives an easy reading of a small
voltage.
Throttle poTester sesition senlector posisor output
tion
voltage
0.58–0.78 V
DCV
CHECKING THE THROTTLE
POSITION SENSOR INPUT
VOLTAGE
1. Disconnect the throttle position
sensor coupler.
2. Start the engine.
3. Inspect:
• Throttle position sensor input voltage
Out of specification→Replace the
CDI unit.
Tester (+) lead → Blue lead "1"
Tester (-) lead → Black/Blue lead
"2"
Throttle poTester sesition senlector posisor input
tion
voltage
4–6 V
DCV-20
Y
L
B/L
10. Put the aligning marks "a" on the
throttle position sensor and carburetor.
11. Stop the engine.
12. Remove the carburetor.
13. Tighten:
• Screw (throttle position sensor)
"1"
Tighten the screw (throttle position
sensor) using the T25 bit.
14. Install the carburetor.
6-8
ENGINE
TUNING
ENGINE
CARBURETOR SETTING
• The air/fuel mixture will vary depending on atmospheric conditions.
Therefore, it is necessary to take
into consideration the air pressure,
ambient temperature, humidity,
etc., when adjusting the carburetor.
• Perform a test run to check for proper engine performance (e.g., throttle response) and spark plug(-s)
discoloration or fouling. Use these
readings to determine the best possible carburetor setting.
It is recommended to keep a record of
all carburetor settings and external
conditions (e.g., atmospheric conditions, track/surface conditions, lap
times) to make future carburetor setting easier.
• The carburetor is a part of the
fuel line. Therefore, be sure to install it in a wellventilated area,
away from flammable objects
and any sources of fire.
• Never look into the carburetor intake. Flames may shoot out from
the pipe if the engine backfires
while it is being started. Gasoline
may be discharged from the accelerator pump nozzle when the
carburetor has been removed.
• The carburetor is extremely sensitive to foreign matter (dirt,
sand, water, etc.). During installation, do not allow foreign matter to get into the carburetor.
• Always handle the carburetor
and its components carefully.
Even slight scratches, bends or
damage to carburetor parts may
prevent the carburetor from
functioning correctly. Carefully
perform all servicing with the appropriate tools and without applying excessive force.
• When the engine is stopped or
when riding at no load, do not
open and close the throttle unnecessarily. Otherwise, too
much fuel may be discharged,
starting may become difficult or
the engine may not run well.
• After installing the carburetor,
check that the throttle operates
correctly and opens and closes
smoothly.
ATMOSPHERIC CONDITIONS AND
CARBURETOR SETTINGS
Air Hutem midip.
ty
Air
pressure
(altitude)
Mixture
Setting
High High
Low
(high)
Richer
Leaner
Low Low
High
(low)
Leaner
Richer
The air density (i.e., concentration of
oxygen in the air) determines the richness or leanness of the air/fuel mixture.
• Higher temperature expands the air
with its resultant reduced density.
• Higher humidity reduces the
amount of oxygen in the air by so
much of the water vapor in the
same air.
• Lower atmospheric pressure (at a
high altitude) reduces the density of
the air.
EFFECT OF SETTING PARTS IN
RELATION TO THROTTLE VALVE
OPENING
CONSTRUCTION OF
CARBURETOR AND SETTING
PARTS
The FLATCR carburetor has a primary main jet. This type of main jet is
perfect for racing machines since it
supplies an even flow of fuel, even at
full load. Use the main jet and the jet
needle to set the carburetor.
The FLATCR carburetor is manufactured with a pilot screw. The pilot
screw adjustment ranges from fully
closed throttle to 1/4 open throttle.
1. Jet needle
2. Pilot air jet
3. Needle jet
4. Main jet
5. Pilot jet
6. Pilot screw
ADJUSTING THE MAIN JET
The richness of the air-fuel mixture at
full throttle can be set by changing the
main jet "1".
Standard main jet
#180
If the air-fuel mixture is too rich or too
lean, the engine power will drop, resulting in poor acceleration.
A.
B.
1.
2.
3.
4.
Closed
Fully open
Pilot screw/pilot jet
Throttle valve cutaway
Jet needle
Main jet
Effects of changing the main jet
(reference)
A.
B.
1.
2.
3.
7-1
Idle
Fully open
#182
#178
#180
7
ENGINE
ADJUSTING THE PILOT SCREW
The richness of the air-fuel mixture
with the throttle fully closed to 1/4
open can be set by turning the pilot
screw "1". Turning in the pilot screw
will make the mixture lean at low
speeds, and turning it out will enrich
it.
Standard pilot screw
position (example)
1-3/4
• If the engine idling speed fluctuates,
turn the pilot screw only 1/2 of a turn
in either direction.
• To optimize the fuel flow at a smaller throttle opening, each machine's
pilot screw has been individually set
at the factory. Before adjusting the
pilot screw, turn it in fully and count
the number of turns. Record this
number as the factory-set number
of turns out.
Effects of adjusting the pilot screw
(reference)
A. Idle
B. Fully open
1. 2-1/4 turns out
2. 1-1/4 turns out
3. 1-3/4 turns out
ADJUSTING THE PILOT JET
The richness of the air-fuel mixture
with the throttle open 1/4 or less can
be set by adjusting the pilot jet "1".
Standard pilot jet
#45
* #42
* Except for USA and CDN
Effects of adjusting the pilot jet
(reference)
A. Idle
B. Fully open
1. #48
2. #42
3. #45
ADJUSTING THE JET NEEDLE
GROOVE POSITION
Adjusting the jet needle "1" position
affects the acceleration when the
throttle is 1/8 to 3/4 open.
1. Too rich at intermediate speeds
• Rough engine operation is felt
and the engine will not pick up
speed smoothly.
Step up the jet needle clip by one
groove and move down the needle to lean out the mixture.
2. Too lean at intermediate speeds
• The engine breathes hard and will
not pick up speed quickly.
Step down the jet needle clip by
one groove and move up the needle to enrich the mixture.
Standard clip posi- No.4
tion
groove
Effects of changing the jet needle
groove position (reference)
A. Idle
B. Fully open
1. No.5 groove
2. No.3 groove
3. No.4 groove
ADJUSTING THE JET NEEDLE
The jet needle is adjusted by changing it.
Standard jet needle
NDJR
* NHKR
* Except for USA and CDN
7-2
The jet needle setting parts, having
the same taper angle, are available in
different straight portion diameters
and in different taper starting positions.
a. Diameter of the straight portion
b. Reference needle
c. 0.5 richer
Changing from NDJR-4 to NCVR-4
has the same effect as a lowering of
0.5 clip position.
NCVR-4
NDJR-4
Effects of changing the jet needle
(reference)
(Diameter of the straight portion)
Changing the diameter of the straight
portion adjusts the air-fuel mixture
when the throttle is 1/8 to 1/4 open.
A. Idle
B. Fully open
RELATIONSHIP WITH THROTTLE
OPENING
The flow of the fuel through the carburetor main system is controlled by
the main jet and then, it is further regulated by the area between the main
nozzle and the jet needle.
The fuel flow relates to the diameter
of the straight portion of the jet needle
with the throttle 1/8 to 1/4 open and
relates to the clip position with the
throttle 1/8 to 3/4 open.
Therefore, the fuel flow is balanced at
each stage of throttle opening by the
combination of the jet needle straight
portion diameter and clip position.
ENGINE
ADJUSTING THE LEAK JET
(ADJUSTING THE ACCELERATOR
PUMP)
The leak jet "1" is a setting part that
adjusts the flow of fuel discharged by
the accelerator pump. Since the accelerator pump operates only when
throttle is open, the leak jet is used to
adjust a fuel mixture ratio for quick
throttle opening and is therefore different from other setting parts that adjust a fuel mixture for each throttle
opening (each engine speed).
1. When the engine breathes hard in
quick throttle opening, select a
leak jet having lower calibrating
No. than standard to enrich the
mixture. <Example> #70 → #60
2. When rough engine operation is
felt in quick throttle opening, select a leak jet having higher calibrating No. than standard to lean
out the mixture. <Example> #70
→ #80
Standard leak jet
#70
*#110
* Except for USA and CDN
Jet needle
Size
Part number
Rich NDJN
5TA-14916-JN
NDJP
5TA-14916-JP
NDJQ
5TA-14916-J1
(STD) NDJR
5TA-14916-JR
NDJS
5TA-14916-JS
NDJT
5TA-14916-JT
Lean NDJU
5TA-14916-JU
Rich NCVN 5TA-14916-VN
NCVP 5TA-14916-VP
NCVQ 5TA-14916-V1
NCVR 5TA-14916-VR
NCVS 5TA-14916-VS
NCVT
5TA-14916-VT
Lean NCVU 5TA-14916-VU
Rich NFLN
5TA-14916-LN
NFLP
5TA-14916-LP
NFLQ
5TA-14916-L1
*(STD) NHKR 5TA-14916-KR
NFLS
5TA-14916-LS
NFLT
5TA-14916-LT
Lean NFLU
5TA-14916-LU
Rich NFPN 5TA-14916-PN
5TA-14916-PP
5TA-14916-P1
NFPR 5TA-14916-PR
CARBURETOR SETTING PARTS
Main jet
NFPP
NFPQ
NFPS
5TA-14916-PS
NFPT
5TA-14916-PT
Size
Part number
#190
4MX-14943-45
#188
4MX-14943-95
#185
4MX-14943-44
#182
4MX-14943-94
#180
4MX-14943-43
#178
4MX-14943-93
#175
4MX-14943-42
#172
4MX-14943-92
#170
4MX-14943-41
Size
Part number
#110
4JT-1494F-29
#50
4MX-14948-07
#120
4JT-1494F-31
#48
4MX-14948-06
#130
4JT-1494F-33
(STD)
#45
4MX-14948-05
#140
4JT-1494F-35
*(STD)
#42
4MX-14948-04
Rich
(STD)
Lean
Pilot jet
Rich
Lean
#40
4MX-14948-03
#38
4MX-14948-02
Lean NFPU 5TA-14916-PU
Leak jet
Rich
(STD)
*(STD)
Lean
Size
Part number
#40
4JT-1494F-03
#50
4JT-1494F-07
#60
4JT-1494F-11
#70
4JT-1494F-15
#80
4JT-1494F-19
#90
4JT-1494F-23
#100
4JT-1494F-27
* Except for USA and CDN
7-3
ENGINE
SPECIFICATIONS OF JET NEEDLE
For USA and CDN
Diameter of straight portion
Rich
N
Rich
Lean
P
Q
R
S
T
U
1 richer
NDJN-5
NDJP-5
NDJQ-5
NDJR-5
NDJS-5
NDJT-5
NDJU-5
0.5 richer
NCVN-4
NCVP-4
NCVQ-4
NCVR-4
NCVS-4
NCVT-4
NCVU-4
STD
NDJN-4
NDJP-4
NDJQ-4
NDJR-4
NDJS-4
NDJT-4
NDJU-4
0.5 leaner
NCVN-3
NCVP-3
NCVQ-3
NCVR-3
NCVS-3
NCVT-3
NCVU-3
1 leaner
NDJN-3
NDJP-3
NDJQ-3
NDJR-3
NDJS-3
NDJT-3
NDJU-3
Lean
Except for USA and CDN
Diameter of straight portion
Rich
Rich
Lean
N
P
Q
R
S
T
U
1 richer
NFLN-7
NFLP-7
NFLQ-7
NHKR-5
NFLS-7
NFLT-7
NFLU-7
0.5 richer
NFPN-6
NFPP-6
NFPQ-6
NFPR-6
NFPS-6
NFPT-6
NFPU-6
STD
NFLN-6
NFLP-6
NFLQ-6
NHKR-4
NFLS-6
NFLT-6
NFLU-6
0.5 leaner
NFPN-5
NFPP-5
NFPQ-5
NFPR-5
NFPS-5
NFPT-5
NFPU-5
1 leaner
NFLN-5
NFLP-5
NFLQ-5
NHKR-3
NFLS-5
NFLT-5
NFLU-5
Lean
EXAMPLES OF CARBURETOR SETTING DEPENDING ON SYMPTOM
Symptom
Setting
Checking
At full throttle
Hard breathing
Shearing noise
Whitish spark plug
↓
Lean mixture
Increase main jet calibration no. (Gradual- Discoloration of spark plug → If tan color, it
ly)
is in good condition.
If cannot be corrected:
Clogged float valve seat
Clogged fuel hose
Clogged fuel cock
Check that the accelerator pump operates
smoothly.
At full throttle
Speed pick-up stops
Slow speed pick-up
Slow response
Sooty spark plug
↓
Rich mixture
Decrease main jet calibration no. (Gradual- Discoloration of spark plug → If tan color, it
ly)
is in good condition.
If cannot be corrected:
Clogged air filter
Fuel overflow from carburetor
Lean mixture
Lower jet needle clip position. (1 groove
down)
Rich mixture
Raise jet needle clip position. (1 groove up)
1/4–3/4 throttle
Hard breathing
Lack of speed
Lower jet needle clip position. (1 groove
down)
1/4–1/2 throttle
Slow speed pick-up
Poor acceleration
Raise jet needle clip position. (1 groove up)
Groove 1
Groove 2
Groove 3
Groove 4
Groove 5
Groove 6
Groove 7
Jet needle
Clip
Leaner
(Standard)
Richer
The clip position is the jet needle groove on
which the clip is installed.
The positions are numbered from the top.
Check that the accelerator pump operates
smoothly. (except for rich mixture symptom).
7-4
ENGINE
Symptom
Setting
Closed to 1/4 throttle
Hard breathing
Speed down
Use jet needle with a smaller diameter.
Closed to 1/4 throttle
Poor acceleration
Use jet needle with a larger diameter.
Raise jet needle clip position. (1 groove up)
Poor response in the low to intermediate speeds
Raise jet needle clip position.
If this has no effect, lower the jet needle clip
position.
Checking
Slow-speed-circuit passage
Clogged → Clean.
Overflow from carburetor
Poor response when throttle is Check overall settings.
Check air filter for fouling.
opened quickly
Use main jet with a lower calibration no.
Check that the accelerator pump operates
Raise jet needle clip position. (1 groove up) smoothly.
If these have no effect, use a main jet with
a higher calibration no. and lower the jet
needle clip position.
This should be taken simply for an example. It is necessary to set the carburetor while checking the operating conditions
of the engine.
7-5
CHASSIS
CHASSIS
SELECTION OF THE SECONDARY
REDUCTION RATIO (SPROCKET)
Secondary reduction ratio =
Number of rear wheel sprocket
teeth/Number of drive sprocket
teeth
Standard secondary
reduction ratio
49/13
(3.769)
* 51/13
(3.923)
* Except for USA and CDN
<Requirement for selection of secondary gear reduction ratio>
• It is generally said that the secondary gear ratio should be reduced for
a longer straight portion of a speed
course and should be increased for
a course with many corners. Actually, however, as the speed depends
on the ground condition of the day
of the race, be sure to run through
the circuit to set the machine suitable for the entire course.
• In actuality, it is very difficult to
achieve settings suitable for the entire course and some settings may
be sacrificed. Thus, the settings
should be matched to the portion of
the course that has the greatest effect on the race result. In such a
case, run through the entire course
while making notes of lap times to
find the best balance; then, determine the secondary reduction ratio.
• If a course has a long straight portion where a machine can run at
maximum speed, the machine is
generally set such that it can develop its maximum revolutions toward
the end of the straight line, with care
taken to avoid the engine over-revving.
Riding technique varies from rider to
rider and the performance of a machine also vary from machine to machine. Therefore, do not imitate other
rider's settings from the beginning but
choose your own setting according to
the level of your riding technique.
DRIVE AND REAR WHEEL
SPROCKETS SETTING PARTS
Part name
Size Part number
Drive
sprocket "1"
(STD) 13T 9383B-13218
Rear wheel
sprocket "2"
47T 17D-25447-50
48T 17D-25448-50
(STD) 49T 17D-25449-50
50T 17D-25450-50
* (STD) 51T 17D-25451-50
52T 17D-25452-50
* Except for USA and CDN
TIRE PRESSURE
Tire pressure should be adjust to suit
the road surface condition of the circuit.
Standard tire pressure:
100 kPa (1.0 kgf/cm2,
15 psi)
• Under a rainy, muddy, sandy, or
slippery condition, the tire pressure
should be lower for a larger area of
contact with the road surface.
Extent of adjustment:
60–80 kPa (0.6–0.8 kgf/
cm2, 9.0–12 psi)
• Under a stony or hard road condition, the tire pressure should be
higher to prevent a flat tire.
Extent of adjustment:
100–120 kPa (1.0–1.2
kgf/cm2, 15–18 psi)
7-6
FRONT FORK SETTING
The front fork setting should be made
depending on the rider's feeling of an
actual run and the circuit conditions.
The front fork setting includes the following three factors:
1. Setting of air spring characteristics
• Change the fork oil amount.
2. Setting of spring preload
• Change the spring.
3. Setting of damping force
• Change the compression damping.
• Change the rebound damping.
The spring acts on the load and
the damping force acts on the
cushion travel speed.
CHANGE IN AMOUNT AND
CHARACTERISTICS OF FORK OIL
Damping characteristic near the final
stroke can be changed by changing
the fork oil amount.
Adjust the oil amount in 5 cm3 (0.2
Imp oz, 0.2 US oz) increments or
decrements. Too small oil amount
causes the front fork to produce a
noise at full rebound or the rider to
feel some pressure on his hands
or body. Alternatively, too large oil
amount will cause the air spring
characteristics to have a tendency
to be stiffer with the consequent
deteriorated performance and
characteristics. Therefore, adjust
the front fork within the specified
range.
Standard oil amount:
350 cm3 (12.3 Imp oz,
11.8 US oz)
* 337 cm3 (11.9 Imp oz,
11.4 US oz)
Extent of adjustment:
300–375 cm3(10.6–13.2
Imp oz, 10.1–12.7 US
oz)
* Except for USA and CDN
CHASSIS
FRONT FORK SETTING PARTS
• Front fork spring "1"
TY
PE
SO
FT
A. Air spring characteristics in
relation to oil amount change
B. Load
C. Stroke
1. Max. oil amount
2. Standard oil amount
3. Min. oil amount
SETTING OF SPRING AFTER
REPLACEMENT
As the front fork setting can be easily
affected by rear suspension, take
care so that the machine front and
rear are balanced (in position, etc.)
when setting the front fork.
1. Use of soft spring
• Change the rebound damping.
Turn out one or two clicks.
• Change the compression damping.
Turn in one or two clicks.
SPRIN
G
RATE
SPRING
PART NUMBER
I.D.
MA
RK
(slit
s)
0.398
1C3-23141-A1
|
0.408
1C3-23141-B1
||
0.418
1C3-23141-C1
|||
0.428
1C3-23141-D1
||||
0.438
1C3-23141-E1
|||||
ST
D
0.449
5XC-23141N0
—
*ST
D
0.459
1C3-23141G1
|-||
STI
FF
0.469
1C3-23141-H1 |-|||
0.479
1C3-23141-J1 |-||||
Generally a stiff spring gives a stiff
riding feeling. Rebound damping
tends to become weaker, resulting in
lack of a sense of contact with the
road surface or in a vibrating handlebar.
2. Remove the stand or block from
the engine and with a rider astride
the seat, measure the sunken
length "b" between the rear wheel
axle center and the rear fender
holding bolt.
*Except for USA and CDN
The I.D. mark (slits) "a" is proved on
the end of the spring.
3. Loosen the locknut "1" and make
adjustment by turning the spring
adjuster "2" to achieve the standard figure from the subtraction of
the length "b" from the length "a".
Standard figure:
90–100 mm (3.5–3.9 in)
Generally a soft spring gives a soft
riding feeling. Rebound damping
tends to become stronger and the
front fork may sink deeply over a series of gaps.
2. Use of stiff spring
• Change the rebound damping.
Turn in one or two clicks.
• Change the compression damping.
Turn out one or two clicks.
CHOOSING SET LENGTH
1. Place a stand or block under the
engine to put the rear wheel
above the floor, and measure the
length "a" between the rear wheel
axle center and the rear fender
holding bolt.
REAR SUSPENSION SETTING
The rear suspension setting should
be made depending on the rider's
feeling of an actual run and the circuit
conditions.
The rear suspension setting includes
the following two factors:
1. Setting of spring preload
• Change the set length of the
spring.
• Change the spring.
2. Setting of damping force
• Change the rebound damping.
• Change the compression damping.
7-7
• If the machine is new and after it is
broken in, the same set length of
the spring may change because of
the initial fatigue, etc. of the spring.
Therefore, be sure to make reevaluation.
• If the standard figure cannot be
achieved by adjusting the spring
adjuster and changing the spring
set length, replace the spring with
an optional one and make readjustment.
CHASSIS
SETTING OF SPRING AFTER
REPLACEMENT
After replacement, be sure to adjust
the spring to the set length [sunken
length 90–100 mm (3.5–3.9 in)] and
set it.
1. Use of soft spring
• Set the soft spring for less rebound damping to compensate
for its less spring load. Run with
the rebound damping adjuster
one or two clicks on the softer
side and readjust it to suit your
preference.
2. Use of stiff spring
• Set the soft spring for more rebound damping to compensate
for its greater spring load. Run
with the rebound damping adjuster one or two clicks on the stiffer
side and readjust it to suit your
preference.
REAR SHOCK ABSORBER
SETTING PARTS
• Rear shock spring "1"
[Equal-pitch steel spring]
• Extent of adjustment (spring preload)
Adjusting the rebound damping will
be followed more or less by a change
in the compression damping. For correction, turn the low compression
damping adjuster on the softer side.
• The I.D. mark "a" is marked at the
end of the spring.
• Spring specification varies according to the color and quantity of I.D.
marks.
TYPE
SPRI
NG
RAT
E
SPRING
PART
NUMBER
(-22212-)
I.D.
MARK/
Q'TY
SOFT
4.3
5UN-00
Brown/1
4.5
5UN-10
Green/1
4.7
5UN-20
Red/1
4.9
5UN-30
Black/1
5.1
5UN-40
Blue/1
STD
STIFF
5.3
5UN-50
(5UN-K0) Yellow/1
(5UN-L0)
5.5
5UN-60
Pink/1
5.7
5UN-70
White/1
When using a rear shock absorber
other than currently installed, use
the one whose overall length "a"
does not exceed the standard as it
may result in faulty performance.
Never use one whose overall
length is greater than standard.
Length "a" of standard
shock:
490 mm (19.29 in)
7-8
SPRING
PART
NUMBER
(-22212-)
Maximum
Minimum
5UN-00
5UN-10
5UN-20
5UN-30
Position
in which
the spring
is turned
in 18 mm
Position
(0.71 in)
in which
from its
the spring
free
is turned
length.
in 1.5 mm
5UN-40
Position
(0.06 in)
5UN-50
in which
from its
(5UN-K0) the spring
free
(5UN-L0) is turned
length.
in 20 mm
5UN-60
5UN-70
(0.79 in)
from its
free
length.
• For the spring preload adjustment,
refer to "ADJUSTING THE REAR
SHOCK ABSORBER SPRING
PRELOAD" in the CHAPTER 3.
CHASSIS
SUSPENSION SETTING (FRONT FORK)
• If any of the following symptoms is experienced with the standard position as the base, make resetting by reference to
the adjustment procedure given in the same chart.
• Before any change, set the rear shock absorber sunken length to the standard figure 90–100 mm (3.5–3.9 in).
Section
Symptom
Stiff over entire
range
Unsmooth movement over entire
range
Jump
○
○
Large
gap
○
○
MediSmall
um
gap
gap
○
○
Poor initial movement
Soft over entire
range, bottoming
out
○
Check
Compression damping
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Oil amount
Decrease oil amount by about 5–10 cm3 (0.2–0.4
Imp oz, 0.2–0.3 US oz).
Spring
Replace with soft spring.
Outer tube
Inner tube
Check for any bends, dents, and other noticeable
scars, etc. If any, replace affected parts.
Slide metal
Replace with a new one for extended use.
Piston metal
Replace with a new one for extended use.
Under bracket tightening torque
Retighten to specified torque.
Rebound damping
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Oil seal
Apply grease in oil seal wall.
Compression damping
Turn adjuster clockwise (about 2 clicks) to increase damping.
Oil amount
Increase oil amount by about 5–10 cm3 (0.2–0.4
Imp oz, 0.2–0.3 US oz).
Spring
Replace with stiff spring.
○
○
○
Adjust
Stiff toward stroke
end
○
Oil amount
Decrease oil amount by about 5 cm3 (0.2 Imp
oz,0.2 US oz).
Soft toward stroke
end, bottoming out
○
Oil amount
Increase oil amount by about 5 cm3 (0.2 Imp
oz,0.2 US oz).
Stiff initial movement
○
Compression damping
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low front, tending to
lower front posture
"Obtrusive" front,
tending to upper
front posture
○
○
○
○
○
○
Compression damping
Turn adjuster clockwise (about 2 clicks) to increase damping.
Rebound damping
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Balance with rear end
Set sunken length for 95–100 mm (3.7–3.9 in)
when one passenger is astride seat (lower rear
posture).
Oil amount
Increase oil amount by about 5 cm3 (0.2 Imp oz,
0.2 US oz).
Compression damping
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Balance with rear end
Set sunken length for 90–95 mm (3.5–3.7 in)
when one passenger is astride seat (upper rear
posture).
Spring
Replace with soft spring.
Oil amount
Decrease oil amount by about 5–10 cm3 (0.2–0.4
Imp oz, 0.2–0.3 US oz).
○
7-9
CHASSIS
SUSPENSION SETTING (REAR SHOCK ABSORBER)
• If any of the following symptoms is experienced with the standard position as the base, make resetting by reference to
the adjustment procedure given in the same chart.
• Adjust the rebound damping in 2-click increments or decrements.
• Adjust the low compression damping in 1-click increments or decrements.
• Adjust the high compression damping in 1/6 turn increments or decrements.
Section
Symptom
Jump
Large
gap
Stiff, tending to sink
○
Spongy and unstable
○
Heavy and dragging
○
Poor road gripping
Bottoming out
Bouncing
Stiff travel
MediSmall
um
gap
gap
○
○
○
○
○
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Spring set length
Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger is astride seat.
Rebound damping
Turn adjuster clockwise (about 2 clicks) to increase damping.
Low compression
damping
Turn adjuster clockwise (about 1 click) to increase
damping.
Spring
Replace with stiff spring.
Rebound damping
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Spring
Replace with soft spring.
Rebound damping
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low compression
damping
Turn adjuster clockwise (about 1 clicks) to increase damping.
High compression
damping
Turn adjuster clockwise (about 1/6 turn) to increase damping.
Spring set length
Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger is astride seat.
Spring
Replace with soft spring.
High compression
damping
Turn adjuster clockwise (about 1/6 turn) to increase damping.
Spring set length
Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger is astride seat.
Spring
Replace with stiff spring.
Rebound damping
Turn adjuster clockwise (about 2 clicks) to increase damping.
Spring
Replace with soft spring.
High compression
damping
Turn adjuster counterclockwise (about 1/6 turn) to
decrease damping.
Spring set length
Set sunken length for 90–100 mm (3.5–3.9 in)
when one passenger is astride seat.
Spring
Replace with soft spring.
○
○
Adjust
Rebound damping
○
○
○
Check
7-10
PRINTED ON RECYCLED PAPER
YAMAHA MOTOR CO., LTD.
2500 SHINGAI IWATA SHIZUOKA JAPAN
PRINTED IN JAPAN
(E)