Yamaha RAPTOR 50 Service manual

YFM50S
SERVICE MANUAL
LIT-11616-17-13
5YF-28197-10
EBS00001
YFM50S
SERVICE MANUAL
©2003 by Yamaha Motor Corporation, U.S.A.
First Edition, April 2003
All rights reserved.
Any reproduction or unauthorized use
without the written permission of
Yamaha Motor Corporation, U.S.A.
is expressly prohibited.
Printed in U.S.A.
LIT-11616-17-13
EBS00002
NOTICE
This manual was produced by the Yamaha Motor Company primarily for use by Yamaha dealers
and their qualified mechanics. It is not possible to include all the knowledge of a mechanic in one
manual, so it is assumed that anyone who uses this book to perform maintenance and repairs on
Yamaha machine has a basic understanding of the mechanical ideas and the procedures of
machine repair. Repairs attempted by anyone without this knowledge are likely to render the
machine unsafe and unfit for use.
Yamaha Motor Company, Ltd. is continually striving to improve all its models. Modifications and significant changes in specifications or procedures will be forwarded to all authorized Yamaha dealers
and will appear in future editions of this manual where applicable.
NOTE:
Designs and specifications are subject to change without notice.
_
EBS00003
IMPORTANT INFORMATION
Particularly important information is distinguished in this manual by the following notations.
The Safety Alert Symbol means ATTENTION! BECOME ALERT! YOUR
SAFETY IS INVOLVED!
WARNING
CAUTION:
NOTE:
Failure to follow WARNING instructions could result in severe injury or death
to the machine operator, a bystander or a person checking or repairing the
machine.
A CAUTION indicates special precautions that must be taken to avoid damage to the machine.
A NOTE provides key information to make procedures easier or clearer.
EBS00004
HOW TO USE THIS MANUAL
MANUAL ORGANIZATION
This manual consists of chapters for the main categories of subjects. (See “symbols”)
1st title 1: This is the title of the chapter with its symbol in the upper right corner of each page.
2nd title 2: This title indicates the section of the chapter and only appears on the first page of each
section. It is located in the upper left corner of the page.
3rd title 3: This title indicates a sub-section that is followed by step-by-step procedures accompanied by corresponding illustrations.
EXPLODED DIAGRAMS
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 4 is provided for removal and disassembly jobs.
2. Numbers 5 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
6. The meanings of the symbol marks are given on the next page.
4. A job instruction chart 7 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 8 are given in addition
to the exploded diagram and the job instruction chart.
1
EBS00005
2
GEN
INFO
SYMBOLS
The following symbols are not relevant to
every machine.
Symbols 1 to 9 indicate the subject of each
chapter.
SPEC
3
4
CHK
ADJ
1 General information
2 Specifications
3 Periodic checks and adjustments
4 Engine
5 Carburetor
6 Drive train
7 Chassis
8 Electrical
9 Troubleshooting
ENG
5
6
CARB
DRIV
7
8
CHAS
–
ELEC
9
Symbols 0 to G indicate the following.
0
0 Serviceable with engine mounted
A Filling fluid
B Lubricant
C Special tool
D Torque
E Wear limit, clearance
F Engine speed
G Electrical data (Ω, V, A)
TRBL
SHTG
A
B
C
D
+
T.
R.
E
F
G
H
I
J
G
E
K
M
L
B
M
M
LS
N
Symbols H to M in the exploded diagrams
indicate the types of lubricants and lubrication
points.
O
LT
New
H Apply engine oil
I Apply gear oil
J Apply molybdenum disulfide oil
K Apply wheel bearing grease
L Apply lithium-soap-based grease
M Apply molybdenum disulfide grease
Symbols N to O in the exploded diagrams
indicate where to apply a locking agent N and
when to install a new part O.
N Apply the locking agent (LOCTITE®)
O Replace
EBS00007
TABLE OF CONTENTS
GENERAL INFORMATION
SPECIFICATIONS
PERIODIC CHECKS AND
ADJUSTMENTS
ENGINE
CARBURETOR
DRIVE TRAIN
CHASSIS
GEN
INFO
1
SPEC
2
CHK
ADJ
3
ENG
4
CARB
5
DRIV
6
CHAS
7
–
ELECTRICAL
TROUBLESHOOTING
+
ELEC
8
TRBL
SHTG
9
CONTENTS
CHAPTER 1
GENERAL INFORMATION
MACHINE IDENTIFICATION...........................................................................1-1
VEHICLE IDENTIFICATION NUMBER .....................................................1-1
MODEL LABEL.......................................................................................... 1-1
IMPORTANT INFORMATION ......................................................................... 1-2
PREPARATION FOR REMOVAL AND DISASSEMBLY........................... 1-2
REPLACEMENT PARTS...........................................................................1-2
GASKETS, OIL SEALS AND O-RINGS .................................................... 1-2
LOCK WASHERS/PLATES AND COTTER PINS ..................................... 1-3
BEARINGS AND OIL SEALS .................................................................... 1-3
CIRCLIPS ..................................................................................................1-3
CHECKING THE CONNECTIONS............................................................ 1-4
SPECIAL TOOLS ............................................................................................ 1-5
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS ........................................................................ 2-1
ENGINE SPECIFICATIONS ............................................................................2-4
CHASSIS SPECIFICATIONS ........................................................................2-11
ELECTRICAL SPECIFICATIONS .................................................................2-12
TIGHTENING TORQUES .............................................................................. 2-14
ENGINE TIGHTENING TORQUES......................................................... 2-14
CHASSIS TIGHTENING TORQUES.......................................................2-15
HOW TO USE THE CONVERSION TABLE.................................................. 2-17
GENERAL TIGHTENING TORQUE SPECIFICATIONS...............................2-17
LUBRICATION POINTS AND LUBRICANT TYPES .................................... 2-18
ENGINE................................................................................................... 2-18
OIL FLOW DIAGRAMS ................................................................................. 2-20
CABLE ROUTING ......................................................................................... 2-22
CHAPTER 3
PERIODIC CHECKS AND ADJUSTMENTS
INTRODUCTION.............................................................................................. 3-1
PERIODIC MAINTENANCE/LUBRICATION .................................................. 3-1
SEAT, FENDERS AND FUEL TANK .............................................................. 3-2
SEAT AND FRONT PANEL ...................................................................... 3-2
FRONT FENDER ......................................................................................3-3
REAR FENDER AND FOOTREST BOARDS ...........................................3-4
FUEL TANK............................................................................................... 3-6
ENGINE ...........................................................................................................3-7
ADJUSTING THE TIMING CHAIN TENSIONER ...................................... 3-7
ADJUSTING THE VALVE CLEARANCE .................................................. 3-8
ADJUSTING THE ENGINE IDLING SPEED ...........................................3-10
ADJUSTING THE THROTTLE LEVER FREE PLAY ..............................3-11
ADJUSTING THE SPEED LIMITER........................................................ 3-12
CHECKING THE SPARK PLUG ............................................................. 3-13
CHECKING THE IGNITION TIMING.......................................................3-14
MEASURING THE COMPRESSION PRESSURE..................................3-15
CHECKING THE ENGINE OIL LEVEL....................................................3-17
CHANGING THE ENGINE OIL ...............................................................3-18
CLEANING THE AIR FILTER ELEMENT................................................ 3-19
CLEANING THE SPARK ARRESTER ....................................................3-20
CHASSIS ....................................................................................................... 3-22
CHECKING THE FRONT AND REAR BRAKE SHOES.......................... 3-22
ADJUSTING THE FRONT BRAKE ......................................................... 3-22
ADJUSTING THE REAR BRAKE............................................................ 3-23
CHECKING THE FINAL GEAR OIL LEVEL ............................................3-24
CHANGING THE FINAL GEAR OIL........................................................ 3-24
CHECKING THE SWINGARM DUST BOOT ..........................................3-25
CHECKING THE STEERING SYSTEM .................................................. 3-26
ADJUSTING THE TOE-IN....................................................................... 3-27
CHECKING THE FRONT AND REAR SHOCK ABSORBERS ............... 3-28
CHECKING THE TIRES..........................................................................3-29
CHECKING THE WHEELS ..................................................................... 3-31
CHECKING AND LUBRICATING THE CABLES .................................... 3-32
LUBRICATING THE LEVERS, STEERING SHAFT
AND STEERING KNUCKLES ................................................................3-32
ELECTRICAL SYSTEM................................................................................. 3-33
CHECKING AND CHARGING THE BATTERY....................................... 3-33
CHECKING THE FUSE...........................................................................3-37
CHAPTER 4
ENGINE
ENGINE ...........................................................................................................4-1
EXHAUST PIPE/MUFFLER, BREATHER HOSE AND LEADS ................ 4-1
ENGINE MOUNTING BOLTS ...................................................................4-2
REMOVING THE ENGINE ........................................................................ 4-4
INSTALLING THE ENGINE....................................................................... 4-4
CYLINDER HEAD............................................................................................ 4-5
REMOVING THE CYLINDER HEAD.........................................................4-7
CHECKING THE CAMSHAFT SPROCKET..............................................4-8
CHECKING THE TAPPET COVERS
AND CAMSHAFT SPROCKET COVER................................................... 4-8
CHECKING THE TIMING CHAIN GUIDES............................................... 4-8
CHECKING THE TIMING CHAIN TENSIONER ASSEMBLY ................... 4-8
CHECKING THE CYLINDER HEAD .........................................................4-9
INSTALLING THE CYLINDER HEAD .....................................................4-10
CAMSHAFT, ROCKER ARMS AND VALVES.............................................. 4-12
REMOVING THE ROCKER ARMS AND CAMSHAFT............................ 4-14
REMOVING THE VALVES AND VALVE SPRINGS ...............................4-14
CHECKING THE CAMSHAFT.................................................................4-15
CHECKING THE ROCKER ARMS AND ROCKER ARM SHAFTS ........ 4-15
CHECKING THE VALVES AND VALVE SPRINGS ................................4-17
INSTALLING THE VALVES AND VALVE SPRINGS ..............................4-21
INSTALLING THE CAMSHAFT AND ROCKER ARMS .......................... 4-22
CYLINDER AND PISTON.............................................................................. 4-23
REMOVING THE PISTON ...................................................................... 4-24
CHECKING THE CYLINDER AND PISTON ...........................................4-24
CHECKING THE PISTON RINGS........................................................... 4-26
CHECKING THE PISTON PIN ................................................................4-27
INSTALLING THE PISTON ..................................................................... 4-28
INSTALLING THE CYLINDER ................................................................4-29
C.D.I. MAGNETO........................................................................................... 4-30
REMOVING THE C.D.I. MAGNETO ROTOR .........................................4-31
CHECKING THE PICKUP COIL/STATOR ASSEMBLY.......................... 4-31
INSTALLING THE C.D.I. MAGNETO ROTOR ........................................ 4-32
INSTALLING THE SHIFT LEVER ........................................................... 4-32
CLUTCH ........................................................................................................4-33
REMOVING THE CLUTCH ..................................................................... 4-35
REMOVING THE PRIMARY DRIVE GEAR ............................................4-35
CHECKING THE FRICTION PLATES.....................................................4-35
CHECKING THE CLUTCH PLATES .......................................................4-36
CHECKING THE CLUTCH SPRINGS.....................................................4-36
CHECKING THE CLUTCH HOUSING ....................................................4-36
CHECKING THE CLUTCH BOSS........................................................... 4-37
CHECKING THE PRESSURE PLATE ....................................................4-37
CHECKING THE CLUTCH BALLS.......................................................... 4-37
CHECKING THE PRIMARY DRIVE GEARS ..........................................4-37
INSTALLING THE PRIMARY DRIVE GEAR...........................................4-38
INSTALLING THE CLUTCH.................................................................... 4-38
STARTER CLUTCH AND OIL PUMP ........................................................... 4-42
CHECKING THE STARTER CLUTCH ....................................................4-44
CHECKING THE OIL PUMP ................................................................... 4-45
SHIFT SHAFT................................................................................................4-47
CHECKING THE SHIFT SHAFT ............................................................. 4-48
CHECKING THE STOPPER LEVER ......................................................4-48
INSTALLING THE STOPPER LEVER ....................................................4-48
INSTALLING THE SHIFT SHAFT ........................................................... 4-48
CRANKCASE ................................................................................................4-49
CRANKCASE BEARINGS....................................................................... 4-50
SEPARATING THE CRANKCASE.......................................................... 4-51
CHECKING THE TIMING CHAIN............................................................ 4-51
CHECKING THE BEARINGS AND OIL SEALS...................................... 4-52
CHECKING THE CRANKCASE ..............................................................4-52
INSTALLING THE BEARINGS................................................................4-52
ASSEMBLING THE CRANKCASE.......................................................... 4-53
CRANKSHAFT ..............................................................................................4-54
CHECKING THE CRANKSHAFT ............................................................ 4-55
INSTALLING THE CRANKSHAFT .......................................................... 4-55
TRANSMISSION............................................................................................ 4-56
REMOVING THE TRANSMISSION ........................................................ 4-57
CHECKING THE SHIFT FORK ...............................................................4-57
CHECKING THE SHIFT DRUM ..............................................................4-58
CHECKING THE TRANSMISSION ......................................................... 4-58
INSTALLING THE TRANSMISSION .......................................................4-59
MIDDLE GEAR ..............................................................................................4-60
REMOVING THE MIDDLE DRIVEN SHAFT...........................................4-61
CHECKING THE PINION GEARS .......................................................... 4-62
SELECTING MIDDLE DRIVEN GEAR SHIMS ....................................... 4-63
INSTALLING THE MIDDLE DRIVEN SHAFT .........................................4-64
MEASURING THE MIDDLE GEAR BACKLASH..................................... 4-66
CHAPTER 5
CARBURETOR
CARBURETOR................................................................................................5-1
DISASSEMBLING THE CARBURETOR................................................... 5-4
CHECKING THE CARBURETOR ............................................................. 5-4
ASSEMBLING THE CARBURETOR.........................................................5-6
INSTALLING THE CARBURETOR ........................................................... 5-6
MEASURING AND ADJUSTING THE FUEL LEVEL ................................5-7
CHAPTER 6
DRIVE TRAIN
TROUBLESHOOTING.....................................................................................6-1
CHECKING NOISES ................................................................................. 6-2
TROUBLESHOOTING CHART .................................................................6-4
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE SHAFT ......................6-5
REAR AXLE/FINAL DRIVE ASSEMBLY................................................... 6-7
REMOVING THE NUTS ............................................................................6-8
REMOVING THE REAR AXLE/FINAL DRIVE ASSEMBLY ......................6-8
DISASSEMBLING THE REAR AXLE HOUSING ...................................... 6-9
DISASSEMBLING THE FINAL GEAR CASE............................................6-9
CHECKING THE REAR AXLE ................................................................6-10
CHECKING THE DRIVE SHAFT............................................................. 6-10
CHECKING THE REAR AXLE HOUSING
AND FINAL DRIVE ASSEMBLY ............................................................ 6-10
ASSEMBLING THE FINAL GEAR CASE................................................ 6-11
ASSEMBLING THE REAR AXLE HOUSING ..........................................6-11
INSTALLING THE REAR AXLE/FINAL DRIVE ASSEMBLY................... 6-12
INSTALLING THE NUTS.........................................................................6-13
CHAPTER 7
CHASSIS
FRONT AND REAR WHEELS ........................................................................ 7-1
FRONT WHEELS ......................................................................................7-1
REAR WHEELS ........................................................................................7-2
CHECKING THE WHEELS ....................................................................... 7-3
CHECKING THE FRONT WHEEL HUBS ................................................. 7-3
CHECKING THE REAR WHEEL HUBS.................................................... 7-4
INSTALLING THE WHEEL HUBS............................................................. 7-4
INSTALLING THE WHEELS ..................................................................... 7-5
FRONT AND REAR BRAKES......................................................................... 7-6
FRONT BRAKE ......................................................................................... 7-6
REAR BRAKE ........................................................................................... 7-7
REMOVING THE BRAKES ....................................................................... 7-9
CHECKING THE BRAKE SHOE PLATES ................................................ 7-9
CHECKING THE BRAKE SHOES............................................................. 7-9
CHECKING THE BRAKE DRUMS .......................................................... 7-10
INSTALLING THE FRONT BRAKES ......................................................7-11
INSTALLING THE REAR BRAKE ........................................................... 7-12
STEERING SYSTEM .....................................................................................7-14
HANDLEBAR........................................................................................... 7-14
REMOVING THE HANDLEBAR GRIPS.................................................. 7-16
REMOVING THE REAR BRAKE SWITCH ............................................. 7-16
CHECKING THE HANDLEBAR ..............................................................7-16
INSTALLING THE HANDLEBAR ............................................................ 7-17
INSTALLING THE HANDLEBAR GRIPS ................................................ 7-17
INSTALLING THE REAR BRAKE LEVER .............................................. 7-18
INSTALLING THE FRONT BRAKE LEVER ASSEMBLY........................ 7-18
STEERING STEM ...................................................................................7-19
REMOVING THE STEERING STEM ......................................................7-20
CHECKING THE STEERING STEM .......................................................7-20
INSTALLING THE STEERING STEM .....................................................7-20
INSTALLING THE LOCK WASHER........................................................ 7-20
TIE-RODS AND STEERING KNUCKLES ............................................... 7-21
REMOVING THE TIE-RODS................................................................... 7-22
CHECKING THE TIE-RODS ................................................................... 7-22
CHECKING THE STEERING KNUCKLES.............................................. 7-22
INSTALLING THE TIE-RODS .................................................................7-23
FRONT SHOCK ABSORBER ASSEMBLIES AND FRONT SWINGARM ... 7-24
REMOVING THE FRONT SWINGARM .................................................. 7-25
CHECKING THE FRONT SWINGARM...................................................7-25
CHECKING THE FRONT SHOCK ABSORBER ASSEMBLIES ............. 7-25
REAR SHOCK ABSORBER AND REAR SWINGARM ................................7-26
REMOVING THE REAR SWINGARM.....................................................7-27
CHECKING THE REAR SHOCK ABSORBER........................................ 7-27
CHECKING THE REAR SWINGARM .....................................................7-28
CHECKING THE DUST BOOT ...............................................................7-28
INSTALLING THE LOCK WASHER........................................................ 7-28
CHAPTER 8
ELECTRICAL
ELECTRICAL COMPONENTS........................................................................ 8-1
CHECKING SWITCH CONTINUITY................................................................8-2
CHECKING THE SWITCHES..........................................................................8-3
CHECKING THE BULBS AND BULB SOCKETS .......................................... 8-4
TYPES OF BULBS .................................................................................... 8-4
CHECKING THE CONDITION OF THE BULBS ....................................... 8-4
CHECKING THE CONDITION OF THE BULB SOCKETS .......................8-6
IGNITION SYSTEM ......................................................................................... 8-7
CIRCUIT DIAGRAM .................................................................................. 8-7
TROUBLESHOOTING ..............................................................................8-8
ELECTRIC STARTING SYSTEM .................................................................. 8-12
CIRCUIT DIAGRAM ................................................................................ 8-12
STARTING CIRCUIT OPERATION......................................................... 8-13
TROUBLESHOOTING ............................................................................8-14
STARTER MOTOR........................................................................................ 8-18
CHECKING THE STARTER MOTOR .....................................................8-19
ASSEMBLING THE STARTER MOTOR................................................. 8-20
CHARGING SYSTEM....................................................................................8-21
CIRCUIT DIAGRAM ................................................................................ 8-21
TROUBLESHOOTING ............................................................................8-22
SIGNAL SYSTEM.......................................................................................... 8-24
CIRCUIT DIAGRAM ................................................................................ 8-24
TROUBLESHOOTING ............................................................................8-25
CHECKING THE SIGNALING SYSTEM ................................................. 8-26
CHAPTER 9
TROUBLESHOOTING
STARTING FAILURE/HARD STARTING .......................................................9-1
FUEL SYSTEM.......................................................................................... 9-1
ELECTRICAL SYSTEM.............................................................................9-1
COMPRESSION SYSTEM........................................................................ 9-2
POOR IDLE SPEED PERFORMANCE ........................................................... 9-2
POOR IDLE SPEED PERFORMANCE.....................................................9-2
POOR MEDIUM AND HIGH-SPEED PERFORMANCE..................................9-2
POOR MEDIUM AND HIGH-SPEED PERFORMANCE ........................... 9-2
FAULTY DRIVE TRAIN ................................................................................... 9-3
FAULTY GEAR SHIFTING..............................................................................9-4
HARD SHIFTING.......................................................................................9-4
SHIFT LEVER DOES NOT MOVE ............................................................ 9-4
JUMPS OUT GEAR................................................................................... 9-4
CLUTCH SLIPPING/DRAGGING.................................................................... 9-4
CLUTCH SLIPPING .................................................................................. 9-4
CLUTCH DRAGGING ............................................................................... 9-4
OVERHEATING............................................................................................... 9-4
OVERHEATING ........................................................................................9-4
FAULTY BRAKE ............................................................................................. 9-5
POOR BRAKING EFFECT........................................................................ 9-5
SHOCK ABSORBER MALFUNCTION ........................................................... 9-5
MALFUNCTION......................................................................................... 9-5
UNSTABLE HANDLING.................................................................................. 9-5
UNSTABLE HANDLING ............................................................................9-5
MACHINE IDENTIFICATION
GEN
INFO
EBS00009
GENERAL INFORMATION
MACHINE IDENTIFICATION
EBS00010
VEHICLE IDENTIFICATION NUMBER
The vehicle identification number 1
stamped into the left side of the frame.
is
EBS00011
MODEL LABEL
The model label 1 is affixed to the frame. This
information will be needed to order spare
parts.
1-1
IMPORTANT INFORMATION
GEN
INFO
EBS00013
IMPORTANT INFORMATION
PREPARATION FOR REMOVAL AND
DISASSEMBLY
1. Before removal and disassembly remove all
dirt, mud, dust and foreign material.
2. Use only the proper tools and cleaning
equipment.
Refer to “SPECIAL TOOLS”.
3. When disassembling always keep mated
parts together. This includes gears, cylinders, pistons and other parts that have been
“mated” through normal wear. Mated parts
must always be reused or replaced as an
assembly.
4. During disassembly, clean all of the parts
and place them in trays in the order of disassembly. This will speed up assembly and
allow for the correct installation of all parts.
5. Keep all parts away from any source of fire.
EBS00014
REPLACEMENT PARTS
1. Use only genuine Yamaha parts for all
replacements. Use oil and grease recommended by Yamaha for all lubrication jobs.
Other brands may be similar in function and
appearance, but inferior in quality.
EBS00015
GASKETS, OIL SEALS AND O-RINGS
1. When overhauling the engine, replace all
gaskets, seals and O-rings. All gasket surfaces, oil seal lips and O-rings must be
cleaned.
2. During reassembly properly oil all mating
parts and bearings, and lubricate the oil
seal lips with grease.
1-2
1
IMPORTANT INFORMATION
GEN
INFO
EBS00016
LOCK WASHERS/PLATES AND COTTER
PINS
After removal, replace all lock washers/plates
1 and cotter pins. After the bolt or nut has
been tightened to specification, bend the lock
tabs along a flat of the bolt or nut.
EBS00017
BEARINGS AND OIL SEALS
Install bearings and oil seals so that the manufacturer’s marks or numbers are visible. When
installing oil seals, lubricate the oil seal lips
with a light coat of lithium-soap-based grease.
Oil bearings liberally when installing, if appropriate.
1 Oil seal
CAUTION:
_
Do not spin the bearing with compressed
air because this will damage the bearing
surfaces.
1 Bearing
EBS00018
CIRCLIPS
Before reassembly, check all circlips carefully
and replace damaged or distorted circlips.
Always replace piston pin clips after one use.
When installing a circlip 1, make sure the
sharp-edged corner 2 is positioned opposite
the thrust 3 that the circlip receives.
4 Shaft
1-3
IMPORTANT INFORMATION
GEN
INFO
EBS00019
CHECKING THE CONNECTIONS
Check the leads, couplers, and connectors for
stains, rust, moisture, etc.
1. Disconnect:
• lead
• coupler
• connector
2. Check:
• lead
• coupler
• connector
Moisture → Dry with an air blower.
Rust/stains → Connect and disconnect several times.
3. Check:
• all connections
Loose connection → Connect properly.
NOTE:
If the pin 1 on the terminal is flattened, bend it
up.
_
4.
•
•
•
Connect:
lead
coupler
connector
NOTE:
Make sure all connections are tight.
_
5. Check:
• continuity (with the pocket tester)
Pocket tester
P/N. YU-03112-C, 90890-03112
NOTE:
• If there is no continuity, clean the terminals.
• When checking the wire harness, perform
steps (1) to (3).
• As a quick remedy, use a contact revitalizer
available at most part stores.
_
1-4
SPECIAL TOOLS
GEN
INFO
EBS00021
SPECIAL TOOLS
The following special tools are necessary for complete and accurate tune-up and assembly. Use
only the appropriate special tools; this will help prevent damage caused by the use of inappropriate
tools or improvised techniques. Special tools may differ by shape and part number from country to
country. In such a case, two types are provided.
When placing an order, refer to the list provided below to avoid any mistakes.
For US and CDN
P/N. YM-, YU-, YS-, YK-, ACCExcept for US and CDN
P/N. 90890Tool No.
Bolt
90890-01085
Weight
90890-01084
Set
YU-01083-A
Tool name/Function
Slide hammer bolt (M8)/weight/set
These tools are used to remove the rocker
arm shaft.
Flywheel puller
90890-01189
YM-01189
This tool is needed to remove the rotor.
Piston pin puller set
90890-01304
YU-01304
This tool is used to remove the piston pin.
Tappet adjusting tool (3 mm)
90890-01311
YM-08035
This tool is necessary for adjusting the
valve clearance.
Fuel level gauge
90890-01312
YM-01312-A
This gauge is used to measure the fuel
level in the float chamber.
Damper rod holder (27 mm)
90890-01388
This tool is needed to loosen and tighten
the middle driven pinion gear bearing
retainer.
1-5
Illustration
SPECIAL TOOLS
Tool No.
Tool name/Function
Axle nut wrench (36 mm)
90890-01422
YM-37132
This tool is needed to loosen or tighten the
rear axle nut.
Ring nut wrench
90890-01430
YM-38404
This tool is needed to loosen and tighten
the final gear case bearing retainer.
Gear lash measurement tool
90890-01467
YM-01467
This tool is used to measure the middle
gear backlash.
Sheave holder
90890-01701
YS-01880-A
This tool is needed to hold the rotor when
removing or installing the rotor nut.
Gauge
90890-03081
YU-33223
Adapter
90890-04082
Compression gauge
Adapter
These tools are needed to measure
engine compression.
Pocket tester
90890-03112
YU-03112-C
This instrument is needed for checking the
electrical system.
Engine tachometer
90890-03113
This tool is needed for observing engine
rpm.
Timing light
90890-03141
YM-33277-A
This tool is necessary for checking ignition
timing.
1-6
GEN
INFO
Illustration
SPECIAL TOOLS
Tool No.
Compressor
90890-04019
YM-04019
Attachment
90890-04108
YM-04108
Holder
90890-04062
YM-04062
Attachment
90890-04096
Tool name/Function
Valve spring compressor
Valve spring compressor attachment
This tool is needed to remove and install
the valve assemblies.
Universal joint holder
Universal joint holder attachment
This tool is needed when removing or
installing the universal joint yoke nut.
Valve guide remover (5 mm)
90890-04097
YM-04097
This tool is needed to remove and install
the valve guide.
Valve guide installer (5 mm)
90890-04098
YM-04098
This tool is needed to install the valve
guide.
Valve guide reamer (5 mm)
90890-04099
This tool is needed to rebore the new
valve guide.
Clutch holder
90890-04100
This tool is needed to hold the clutch boss
when removing or installing the clutch
boss nut.
Pinion gear fix clamp
90890-04129
YM-04129
This tool is used to hold the drive axle/middle drive pinion gear assembly.
Ignition checker
90890-06754
This instrument is necessary for checking
the ignition system components.
1-7
GEN
INFO
Illustration
SPECIAL TOOLS
Tool No.
Bond
90890-85505
Sealant
ACC-11001-05-01
Tool name/Function
Yamaha bond No. 1215
Sealant (Quick Gasket®)
This sealant (bond) is used on crankcase
mating surfaces, etc.
27-mm hexagon wrench
YM-01363
This tool is needed to loosen and tighten
the middle driven pinion gear bearing
retainer.
Dynamic spark tester
YM-34487
This instrument is necessary for checking
the ignition system components.
Inductive self-powered tachometer
YU-8036-B
This tool is needed for observing engine
rpm.
1-8
GEN
INFO
Illustration
GENERAL SPECIFICATIONS
SPEC
EBS01001
SPECIFICATIONS
GENERAL SPECIFICATIONS
Item
Standard
Model code
Dimensions
Overall length
Overall width
Overall height
Seat height
Wheelbase
Minimum ground clearance
Minimum turning radius
Basic weight
With oil and full fuel tank
Engine
Engine type
Cylinder arrangement
Displacement
Bore × stroke
Compression ratio
Standard compression pressure (at sea level)
Starting system
Lubrication system
Oil type or grade
Engine oil
0°
10°
30°
50°
70°
90°
110°
130°F
5YF1
1,537 mm (60.5 in)
825 mm (32.5 in)
915 mm (36.0 in)
618 mm (24.3 in)
1,030 mm (40.6 in)
70 mm (2.76 in)
2,300 mm (90.6 in)
115 kg (253 lb)
Air-cooled 4-stroke, SOHC
Forward-inclined single cylinder
49 cm3
39.0 × 41.4 mm (1.54 × 1.63 in)
10.0 : 1
1,200 kPa
(12.0 kg/cm2, 170.6 psi) at 1,000 r/min
Electric starter
Wet sump
API service SE, SF, SG type or higher
YAMALUBE 4 (20W40) or SAE 20W40
YAMALUBE 4 (10W30) or SAE 10W30
SAE 5W30
-20°
-10°
0°
10°
Final gear oil
Oil capacity
Engine oil
Periodic oil change
Total amount
Final gear case oil
Total amount
Air filter
20°
30°
40°
50°C
SAE 80API “GL-4” Hypoid gear oil
0.80 L (0.70 Imp qt, 0.85 US qt)
0.95 L (0.84 Imp qt, 1.00 US qt)
0.12 L (0.11 Imp qt, 0.13 US qt)
Wet type element
2-1
GENERAL SPECIFICATIONS
Item
Fuel
Type
Fuel tank capacity
Fuel reserve amount
Carburetor
Type/quantity
Manufacturer
Spark plug
Type/manufacturer
Spark plug gap
Clutch type
Transmission
Primary reduction system
Primary reduction ratio
Secondary reduction system
Secondary reduction ratio
Operation
Gear ratio
1st gear
Chassis
Frame type
Caster angle
Camber angle
Kingpin angle
Trail
Tread (STD)
Toe-in
Tire
Type
Size
Manufacturer
Type
Tire pressure (cold tire)
Maximum load*
Off-road riding
SPEC
Standard
Unleaded gasoline only
6.8 L (1.50 Imp gal, 1.80 US gal)
0.9 L (0.20 Imp gal, 0.24 US gal)
VM16SH/1
MIKUNI
CR7HS/NGK
0.6 ~ 0.7 mm (0.024 ~ 0.028 in)
Wet, multiple-disc automatic
Spur gear
65/20 (3.250)
Shaft drive
19/18 × 34/10 (3.588)
Left hand operation
38/14 (2.714)
front
rear
front
rear
front
rear
front
rear
front
rear
*Load in total weight of rider accessories
Steel tube frame
1.0°
2.0°
10°
3.4 mm (0.13 in)
630 mm (24.80 in)
665 mm (26.18 in)
0 ~ 10 mm (0 ~ 0.39 in)
Tubeless
AT16 × 7-7
AT16 × 8-7
DUNLOP
DUNLOP
KT145
KT145
40 kg (88 lb)
17 ~ 23 kPa (0.17 ~ 0.23 kgf/cm2, 2.5 ~ 3.3 psi)
17 ~ 23 kPa (0.17 ~ 0.23 kgf/cm2, 2.5 ~ 3.3 psi)
2-2
2
GENERAL SPECIFICATIONS
Item
Brake
Front brake
Rear brake
Suspension
Front suspension
Rear suspension
Shock absorber
Front shock absorber
Rear shock absorber
Wheel travel
Front wheel travel
Rear wheel travel
Electrical
Ignition system
Generator system
Battery type
Battery capacity
Bulb wattage × quantity
Neutral indicator light
SPEC
Standard
type
operation
type
operation
Drum brake
Right hand operation
Drum brake
Left hand operation
Leading arm
Swingarm
Coil spring/oil damper
Coil spring/oil damper
57 mm (2.24 in)
56 mm (2.20 in)
C.D.I.
A.C. magneto
12N7D-3B
12 V 7 AH
12 V 1.7 W × 1
2-3
ENGINE SPECIFICATIONS
SPEC
EBS01002
ENGINE SPECIFICATIONS
Item
Standard
Cylinder head
Warp limit
Limit
----
0.05 mm
(0.002 in)
Taper limit
39.000 ~ 39.005 mm
(1.5354 ~ 1.5356 in)
----
Maximum out-of-round
----
39.105 mm
(1.5396 in)
0.05 mm
(0.002 in)
0.01 mm
(0.0004 in)
Cylinder
Bore size
Camshaft
Drive method
Cam dimensions
Chain drive (Left)
----
A
B
Intake
“A”
“B”
Exhaust
“A”
“B”
Camshaft runout limit
Timing chain
Timing chain type/No. of links
Timing chain adjustment method
25.300 ~ 25.310 mm
(0.9961 ~ 0.9965 in)
20.994 ~ 21.094 mm
(0.8265 ~ 0.8305 in)
25.301 ~ 25.311 mm
(0.9961 ~ 0.9965 in)
21.021 ~ 21.121 mm
(0.8276 ~ 0.8315 in)
----
Bush chain/82
Manual
2-4
25.200 mm
(0.9921 in)
20.894 mm
(0.8226 in)
25.201 mm
(0.9922 in)
20.921 mm
(0.8237 in)
0.03 mm
(0.0012 in)
-------
ENGINE SPECIFICATIONS
Item
Standard
Rocker arm/rocker arm shaft
Rocker arm inside diameter
Rocker arm shaft outside diameter
Rocker-arm-to-rocker-arm-shaft clearance
Valve, valve seat, valve guide
Valve clearance (cold)
IN
EX
10.000 ~ 10.015 mm
(0.3937 ~ 0.3943 in)
9.981 ~ 9.991 mm
(0.3930 ~ 0.3933 in)
0.009 ~ 0.034 mm
(0.0004 ~ 0.0013 in)
0.05 ~ 0.10 mm
(0.002 ~ 0.004 in)
0.075 ~ 0.125 mm
(0.003 ~ 0.005 in)
SPEC
Limit
------0.08 mm
(0.0031 in)
-------
Valve dimensions
B
C
D
A
Head Diameter
“A” head diameter
Face Width
IN
EX
“B” face width
IN
EX
“C” seat width
IN
EX
“D” margin thickness
IN
EX
Stem outside diameter
IN
EX
Guide inside diameter
IN
EX
Seat Width
19.9 ~ 20.1 mm
(0.7835 ~ 0.7913 in)
16.7 ~ 16.9 mm
(0.6575 ~ 0.6654 in)
1.10 ~ 2.30 mm
(0.0433 ~ 0.0906 in)
1.30 ~ 2.40 mm
(0.0512 ~ 0.0945 in)
0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)
0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)
0.5 ~ 0.9 mm
(0.0197 ~ 0.0354 in)
0.6 ~ 1.0 mm
(0.0236 ~ 0.0394 in)
4.975 ~ 4.990 mm
(0.1959 ~ 0.1965 in)
4.960 ~ 4.975 mm
(0.1953 ~ 0.1959 in)
5.000 ~ 5.012 mm
(0.1969 ~ 0.1973 in)
5.000 ~ 5.012 mm
(0.1969 ~ 0.1973 in)
2-5
Margin Thickness
------------1.6 mm
(0.0630 in)
1.6 mm
(0.0630 in)
1.6 mm
(0.0630 in)
1.6 mm
(0.0630 in)
4.950 mm
(0.1949 in)
4.953 mm
(0.1950 in)
5.030 mm
(0.1980 in)
5.030 mm
(0.1980 in)
ENGINE SPECIFICATIONS
Item
Stem-to-guide clearance
Standard
IN
0.08 mm
(0.0031 in)
0.10 mm
(0.0039 in)
0.02 mm
(0.0008 in)
0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)
0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)
1.6 mm
(0.0630 in)
1.6 mm
(0.0630 in)
IN
32.00 mm (1.26 in)
EX
32.00 mm (1.26 in)
30.40 mm
(1.20 in)
30.40 mm
(1.20 in)
IN
136 ~ 158 N at 24.6 mm
(13.87 ~ 16.11 kg,
30.57 ~ 35.52 lb at 0.97 in)
136 ~ 158 N at 24.6 mm
(13.87 ~ 16.11 kg,
30.57 ~ 35.52 lb at 0.97 in)
Stem runout limit
IN
EX
Valve spring
Free length
Compressed pressure
(installed)
EX
Tilt limit
IN
IN
EX
----
----
2.5°/1.4 mm
(2.5°/0.06 in)
2.5°/1.4 mm
(2.5°/0.06 in)
EX
Direction of winding
(top view)
Limit
0.010 ~ 0.037 mm
(0.0004 ~ 0.0015 in)
0.025 ~ 0.052 mm
(0.0010 ~ 0.0020 in)
----
EX
Valve seat width
SPEC
Clockwise
Clockwise
2-6
-------
ENGINE SPECIFICATIONS
Item
Standard
Piston
Piston to cylinder clearance
Piston size “D”
SPEC
Limit
0.025 ~ 0.045 mm
(0.0010 ~ 0.0018 in)
38.960 ~ 38.975 mm
(1.5339 ~ 1.5344 in)
0.15 mm
(0.0059 in)
----
5.0 mm (0.20 in)
39.5 mm (1.56 in)
40.0 mm (1.57 in)
0.5 mm (0.02 in)
Intake side
13.002 ~ 13.013 mm
(0.5119 ~ 0.5123 in)
12.996 ~ 13.000 mm
(0.5117 ~ 0.5118 in)
---------------13.043 mm
(0.5135 in)
12.976 mm
(0.5109 in)
Barrel
1.0 × 1.7 mm
(0.0394 × 0.0669 in)
0.08 ~ 0.20 mm
(0.0031 ~ 0.0079 in)
0.030 ~ 0.065 mm
(0.0012 ~ 0.0026 in)
-------
H
D
Measuring point “H”
Oversize
2nd
4th
Piston off-set
Piston off-set direction
Piston pin bore inside diameter
Piston pin outside diameter
Piston rings
Top ring
B
T
Type
Dimensions (B × T)
End gap (installed)
Side clearance (installed)
0.45 mm
(0.0177 in)
0.12 mm
(0.0047 in)
2nd ring
B
T
Type
Dimensions (B × T)
End gap (installed)
Side clearance
Taper
1.0 × 1.7 mm
(0.0394 × 0.0669 in)
0.05 ~ 0.20 mm
(0.0020 ~ 0.0079 in)
0.020 ~ 0.055 mm
(0.0008 ~ 0.0022 in)
2-7
------0.55 mm
(0.0217 in)
0.12 mm
(0.0047 in)
ENGINE SPECIFICATIONS
Item
Standard
SPEC
Limit
Oil ring
B
T
Dimensions (B × T)
2.0 × 2.0 mm
(0.0787 × 0.0787 in)
0.20 ~ 0.70 mm
(0.0079 ~ 0.0276 in)
End gap (installed)
-------
Crankshaft
F
C2
C1
E
D
A
Crank width “A”
Runout limit C1
C2
Big end side clearance “D”
Big end radial clearance “E”
Small end free play “F”
Clutch
Friction plate 1 (with black color marking)
Thickness
Quantity
Friction plate 2
Thickness
Quantity
40.20 ~ 40.25 mm
(1.5827 ~ 1.5846 in)
------0.10 ~ 0.40 mm
(0.0039 ~ 0.0157 in)
0.004 ~ 0.019 mm
(0.0002 ~ 0.0007 in)
0.80 ~ 1.00 mm
(0.0315 ~ 0.0394 in)
---0.05 mm
(0.0020 in)
0.04 mm
(0.0016 in)
0.50 mm
(0.0197 in)
---1.50 mm
(0.0591 in)
2.92 ~ 3.08 mm
(0.115 ~ 0.121 in)
4
2.90 mm
(0.114 in)
----
2.92 ~ 3.08 mm
(0.115 ~ 0.121 in)
1
2.90 mm
(0.114 in)
----
2-8
ENGINE SPECIFICATIONS
Item
SPEC
Standard
Limit
Clutch plate 1
Thickness
Quantity
Maximum warpage
1.4 mm (0.055 in)
1
----
------0.06 mm
(0.002 in)
Clutch plate 2
Thickness
Quantity
Maximum warpage
1.2 ~ 1.6 mm (0.047 ~ 0.063 in)
3
----
------0.06 mm
(0.002 in)
Clutch spring
Free length
31.9 mm (1.26 in)
30.3 mm
(1.19 in)
----
Quantity
Automatic centrifugal clutch
Clutch-in revolution
Clutch-stall revolution
Transmission
Main axle deflection limit
----
Drive axle deflection limit
----
Shifter
Shifter type
Carburetors
I. D. mark
Main jet
Air jet
Jet needle
Needle jet
Cutaway
Pilot outlet
Pilot jet
Valve seat size
Fuel level
Engine idle speed
Intake vacuum
8
2,300 ~ 2,500 r/min
3,000 ~ 3,200 r/min
(M.J)
(A.J)
(J.N)
(N.J)
(C.A)
(P.O)
(P.J)
(V.S)
(F.L)
------0.08 mm
(0.0031 in)
0.08 mm
(0.0031 in)
Shift drum and guide bar
----
5YF1 00
#72.5
1.2
3PZ13-2
D-8M
3
0.7
#15
1.2
4.0 ~ 5.0 mm (0.16 ~ 0.20 in)
Below the float chamber mating
surface
1,750 ~ 1,850 r/min
30 kPa (225 mmHg, 8.9 inHg)
-------------------------------
2-9
-------
ENGINE SPECIFICATIONS
Item
SPEC
Standard
Oil pump
Oil pump type
Inner-rotor-to-outer-rotor-tip clearance
Limit
Trochoid
0.05 ~ 0.07 mm
(0.002 ~ 0.003 in)
0.013 ~ 0.036 mm
(0.0005 ~ 0.0014 in)
0.06 ~ 0.10 mm
(0.0024 ~ 0.0039 in)
Outer-rotor-to-oil-pump-housing clearance
Oil-pump-housing-to-inner-rotor-and-outerrotor clearance
Shaft drive
Middle gear backlash
---0.15 mm
(0.006 in)
0.106 mm
(0.0042 in)
0.17 mm
(0.0067 in)
0.17 ~ 0.31 mm
(0.007 ~ 0.012 in)
0.17 ~ 0.31 mm
(0.007 ~ 0.012 in)
Final gear backlash
-------
Lubrication chart
: Pressure feed
: Splashed scavenge
Crankshaft
pin
Piston
Transmission
Camshaft
Piston pin
Rocker arm
Oil pump
Clutch
Oil strainer
Oil pan
2 - 10
Timing
chain area
Valve
CHASSIS SPECIFICATIONS
SPEC
EBS01003
CHASSIS SPECIFICATIONS
Item
Front suspension
Shock absorber travel
Optional spring
Rear suspension
Shock absorber travel
Optional spring
Front wheel
Type
Rim size
Rim material
Rim runout limit
Rear wheel
Type
Rim size
Rim material
Rim runout limit
Standard
58 mm (2.28 in)
No
-------
lateral
----
radial
Panel wheel
7 × 6.5 AT
Steel
----
lateral
----
Leading, trailing
110.0 mm (4.33 in)
4.0 mm (0.16 in)
Shoe spring free length
Rear drum brake
Type
Brake drum inside diameter
54.0 mm (2.13 in)
Leading, trailing
130.0 mm (5.12 in)
Lining thickness
Throttle lever free play
-------
radial
Lining thickness
Shoe spring free length
Brake lever and brake pedal
Brake lever free play (pivot)
60 mm (2.36 in)
No
Panel wheel
7 × 5.5 AT
Steel
----
Front drum brake
Type
Brake drum inside diameter
4.0 mm (0.16 in)
36.5 mm (1.44 in)
front
rear
Limit
10 ~ 12 mm (0.39 ~ 0.47 in)
7 ~ 10 mm (0.28 ~ 0.39 in)
1.5 ~ 5.0 mm (0.06 ~ 0.20 in)
2 - 11
---------2.0 mm
(0.08 in)
2.0 mm
(0.08 in)
---------2.0 mm
(0.08 in)
2.0 mm
(0.08 in)
---110.5 mm
(4.35 mm)
2.0 mm
(0.08 in)
------130.5 mm
(5.14 in)
2.0 mm
(0.08 in)
-------------
ELECTRICAL SPECIFICATIONS
SPEC
EBS01004
ELECTRICAL SPECIFICATIONS
Item
Voltage
Ignition system
Ignition timing (B.T.D.C.)
Advanced timing (B.T.D.C.)
Advancer type
C.D.I.
Magneto model/manufacturer
Pickup coil resistance/color
Source coil resistance/color
C.D.I. unit model/manufacturer
Ignition coil
Model/manufacturer
Minimum spark gap
Primary winding resistance
Secondary winding resistance
Spark plug cap
Type
Resistance
Charging system
Type
Model/manufacturer
Nominal output
Charging coil resistance/color
Lighting coil resistance
Rectifier/regulator
Regulator type
No-load regulated voltage (DC)
No-load regulated voltage (AC)
Model/manufacturer
Capacity (DC)
Capacity (AC)
Withstand voltage
Standard
Limit
12 V
----
10°/1,700 r/min
30°/5,000 r/min
Electrical (analogue)
----------
F2FM/YAMAHA
264 ~ 396 Ω at 20 °C (68 °F)/
White/Red—White/Blue
304 ~ 456 Ω at 20 °C (68 °F)/
Black/Red—Green/White
5YF/YAMAHA
-------
2JN/YAMAHA
6 mm (0.24 in)
0.18 ~ 0.28 Ω at 20 °C (68 °F)
6.32 ~ 9.48 kΩ at 20 °C (68 °F)
-------------
Resin
10 kΩ
-------
A.C. magneto
F2FM/YAMAHA
14 V 45 W at 5,000 r/min
0.72 ~ 1.08 Ω at 20 °C (68 °F)/
White—Black
0.32 ~ 0.48 Ω at 20 °C (68 °F)/
Yellow/Red—Black
-------------
Semi conductor-short circuit
14.0 ~ 15.0 V
13.0 ~ 14.0 V
SH704-12/SHINDENGEN
5A
8A
200 V
----------------------
2 - 12
-------
----
ELECTRICAL SPECIFICATIONS
Item
Electric starter system
Type
Starter motor
Model/manufacturer
Output
Armature coil resistance
Brush overall length
Spring force
Commutator diameter
Mica undercut
Starter relay
Model/manufacturer
Amperage rating
Coil winding resistance
Starting circuit cut-off relay
Model/manufacturer
Coil resistance
Diode
Circuit breakers
Type
Amperage for individual circuit
Main fuse
Reserve
SPEC
Standard
Constant mesh
ADB4A5/DENSO
0.2 kW
0.029 ~ 0.035 Ω at 20 °C (68 °F)
6.0 mm (0.24 in)
3.24 ~ 4.22 N
(330 ~ 430 gf, 11.66 ~ 15.19 oz)
16.5 mm (0.65 in)
1 mm (0.04 in)
Limit
------------3.5 mm
(0.14 in)
---15.5 mm
(0.61 in)
----
MS5E-661/JIDECO
100 A
4.18 ~ 4.62 Ω at 20 °C (68 °F)
----------
ACA12115-3/MATSUSHITA
72 ~ 88 Ω at 20 °C (68 °F)
Yes
----------
Fuse
----
5A×1
5A×1
-------
2 - 13
TIGHTENING TORQUES
SPEC
EBS01005
TIGHTENING TORQUES
ENGINE TIGHTENING TORQUES
Part to be tightened
Cylinder head (exhaust pipe)
Intake and exhaust tappet cover
Camshaft sprocket cover
Cylinder head
Spark plug
C.D.I. magneto rotor
Valve adjuster
Camshaft sprocket
Timing chain tensioner
Timing chain tension adjuster locknut
Oil pump
Engine oil drain bolt
Intake manifold
Carburetor
Exhaust pipe
Muffler
Spark arrester
Muffler purging bolt
Crankcase
Crankcase (cylinder head)
Main axle bearing retainer
Drive axle/middle drive pinion gear
assembly plate
Clutch cover
C.D.I. magneto cover
Starter clutch
Primary drive gear
Clutch boss
Push plate
Middle driven shaft bearing retainer
Universal joint yoke
Middle driven shaft bearing housing
Shift drum retainer
Shift shaft spring stopper
Shift drum stopper lever
Shift lever
Stator assembly
Starter motor
Part name
Thread
Q’ty
size
Tightening torque
Nm m · kg ft · lb
Stud bolt
—
Screw
Nut
Bolt
—
Nut
Nut
Bolt
—
Nut
Screw
Bolt
Screw
Screw
Nut
Bolt
Screw
Bolt
Screw
Stud bolt
Screw
M6
M45
M6
M6
M6
M10
M10
M5
M8
M18
M6
M6
M12
M6
M6
M6
M8
M6
M6
M6
M6
M6
2
2
2
4
2
1
1
2
1
1
1
2
1
2
2
2
2
2
1
9
4
2
7
18
7
12
10
13
40
7
20
18
7
7
20
7
7
10
25
8
10
7
10
8
0.7
1.8
0.7
1.2
1.0
1.3
4.0
0.7
2.0
1.8
0.7
0.7
2.0
0.7
0.7
1.0
2.5
0.8
1.0
0.7
1.0
0.8
5.1
13
5.1
8.7
7.2
9.4
29
5.1
14
13
5.1
5.1
14
5.1
5.1
7.2
18
5.8
7.2
5.1
7.2
5.8
Bolt
M6
3
10
1.0
7.2
Screw
Screw
Screw
Nut
Nut
Screw
—
Nut
Bolt
Screw
Bolt
Bolt
Bolt
Screw
Bolt
M6
M6
M6
M12
M14
M6
M42
M12
M6
M6
M8
M6
M6
M6
M6
3
9
3
1
1
4
1
1
3
2
1
1
1
2
2
7
7
10
50
60
8
60
90
10
8
25
10
10
7
10
0.7
0.7
1.0
5.0
6.0
0.8
6.0
9.0
1.0
0.8
2.5
1.0
1.0
0.7
1.0
5.1
5.1
7.2
36
43
5.8
43
65
7.2
5.8
18
7.2
7.2
5.1
7.2
2 - 14
Remarks
LT
Stake
LT
Stake
Stake
LT
LT
LT
LT
TIGHTENING TORQUES
Part to be tightened
Neutral switch
Spark arrester tailpipe
Purging bolt
Part name
—
Screw
Bolt
Thread
Q’ty
size
M10
M6
M6
1
2
1
SPEC
Tightening torque
Nm m · kg ft · lb
20
8
10
2.0
0.8
1.0
Remarks
14
5.8
7.2
EBS01006
CHASSIS TIGHTENING TORQUES
Part to be tightened
Thread size
Engine and frame
Rear swingarm and frame
Rear swingarm and swingarm guard
Rear shock absorber and frame
Rear shock absorber and rear axle housing
Front swingarm and frame
Front shock absorber and frame
Front shock absorber and front swingarm
Steering knuckle and front swingarm
Steering knuckle and tie-rod ball joint
Steering stem and tie-rod ball joint
Tie-rod locknut
Steering stem and frame
Steering stem bushing and frame
Handlebar holder and steering stem
Throttle lever and housing
Front wheel and brake drum
Front axle and brake drum
Front brake camshaft and camshaft lever
Rear brake camshaft and camshaft lever
Rear axle and nut
Rear wheel and wheel hub
Rear axle and wheel hub
Rear brake drum boss and brake drum
Rear axle housing and rear swingarm
Footrest board bracket and frame
Front bumper and frame
Front bumper and dummy headlight
Front bumper and front fender
Front fender and frame
Front fender stay and frame
Footrest board and bracket
Rear fender and frame
Rear swingarm and final gear case
Final gear case and rear axle housing
M8
M12
M8
M10
M10
M12
M10
M12
M10
M10
M10
M10
M10
M8
M8
M8
M8
M14
M6
M6
M28
M8
M12
M8
M10
M12
M8
M6
M6
M6
M6
M6
M6
M8
M6
2 - 15
Tightening torque
Nm m · kg ft · lb
33
85
23
45
45
60
45
45
30
40
40
15
35
23
20
8
28
70
9
9
3.3
8.5
2.3
4.5
4.5
6.0
4.5
4.5
3.0
4.0
4.0
1.5
3.5
2.3
2.0
0.8
2.8
7.0
0.9
0.9
Remarks
24
61
17
32
32
43
32
32
22
29
29
11
25
17
14
5.8
20
50
6.5
6.5
See NOTE.
28
70
21
40
85
23
7
7
7
7
7
7
20
20
2.8
7.0
2.1
4.0
8.5
2.3
0.7
0.7
0.7
0.7
0.7
0.7
2.0
2.0
20
50
15
29
61
17
5.1
5.1
5.1
5.1
5.1
5.1
14
14
LT
TIGHTENING TORQUES
Part to be tightened
Thread size
Final gear oil drain plug
Final gear case bearing retainer
Final drive pinion gear and bearing
Rear axle housing bearing retainer
M14
M55
M20
M58
SPEC
Tightening torque
Nm m · kg ft · lb
23
80
12
110
2.3
8.0
1.2
11.0
Remarks
17
58
8.7
80
NOTE:
1. Before tightening the nuts, apply locking agent (LOCTITE®) to rear axle threads.
2. Tighten the inside nut to 110 Nm (11.0 m · kg, 80 ft · lb).
3. Tighten the outside nut to 130 Nm (13.0 m · kg, 94 ft · lb) while holding the inside nut.
4. Loosen the inside nut to 160 Nm (16.0 m · kg, 115 ft · lb) while holding the outside nut.
2 - 16
LT
LT
LT
HOW TO USE THE CONVERSION TABLE/
GENERAL TIGHTENING TORQUE SPECIFICATIONS
SPEC
EBS00022
EBS00023
HOW TO USE THE CONVERSION
TABLE
GENERAL TIGHTENING TORQUE
SPECIFICATIONS
All specification data in this manual are listed
in SI and METRIC UNITS.
Use this table to convert METRIC unit data to
IMPERIAL unit data.
This chart specifies tightening torques for standard fasteners with a standard ISO thread
pitch. Tightening torque specifications for special components or assemblies are provided
for each chapter of this manual. To avoid
warpage, tighten multi-fastener assemblies in
a crisscross pattern and progressive stages
until the specified tightening torque is reached.
Unless otherwise specified, tightening torque
specifications require clean, dry threads. Components should be at room temperature.
Ex.
METRIC
MULTIPLIER
IMPERIAL
** mm
×
0.03937
=
** in
2 mm
×
0.03937
=
0.08 in
CONVERSION TABLE
METRIC TO IMPERIAL
Metric unit
Multiplier
Imperial unit
m · kg
m · kg
cm · kg
cm · kg
7.233
86.794
0.0723
0.8679
ft · lb
in · lb
ft · lb
in · lb
Weight
kg
g
2.205
0.03527
lb
oz
Speed
km/h
0.6214
mph
Distance
km
m
m
cm
mm
0.6214
3.281
1.094
0.3937
0.03937
mi
ft
yd
in
in
Volume/
Capacity
cc (cm3)
cc (cm3)
lt (liter)
lt (liter)
0.03527
0.06102
0.8799
0.2199
oz (Imp liq.)
cu · in
qt (Imp liq.)
gal (Imp liq.)
Misc.
kg/mm
kg/cm2
Centigrade
(°C)
55.997
14.2234
9/5+32
lb/in
psi (lb/in2)
Fahrenheit
(°F)
Torque
A: Distance between flats
B: Outside thread diameter
A
(nut)
2 - 17
B
(bolt)
General tightening
torques
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
13.0
94
LUBRICATION POINTS AND LUBRICANT TYPES
SPEC
EBS00024
LUBRICATION POINTS AND LUBRICANT TYPES
ENGINE
Lubrication points
Oil seal lips
Lubricant
LS
Bearings
E
O-rings
LS
Tappet cover thread
E
Crankshaft pin
E
Connecting rod (bearing)
E
Crankshaft, oil seal
E
Piston, piston ring
E
Piston pin
E
Valve stem
M
Valve stem end
E
Rocker arm
M
Rocker arm shaft
E
Camshaft lobe
M
Camshaft sprocket
E
Timing chain tensioner
E
Intake side timing chain guide
E
Oil pump assembly
E
Starter idle gear shaft
M
Starter wheel gear
E
Primary driven gear, spacer
E
Clutch push rod, oil seal
E
Drive axle, 1st wheel gear
M
Drive axle dog splines
M
Drive axle dog shift fork groove
E
Middle drive/driven pinion gear
E
Shift drum
E
Shift fork guide bar, O-ring
E
Shift shaft
E
Shift shaft washer
LS
Middle driven pinion gear, universal joint yoke, drive shaft, coupling gear,
final drive pinion gear splines
LS
Final drive pinion gear, ring gear
E
Sealant
(Quick Gasket®)
Yamaha Bond
No.1215
Crankcase mating surface
2 - 18
LUBRICATION POINTS AND LUBRICANT TYPES
Lubrication points
Final gear case and rear axle housing mating surface
2 - 19
SPEC
Lubricant
Sealant
(Quick Gasket®)
Yamaha Bond
No.1215
OIL FLOW DIAGRAMS
EBS00026
OIL FLOW DIAGRAMS
1 Camshaft
2 Crankshaft
3 Main axle
4 Drive axle
2 - 20
SPEC
OIL FLOW DIAGRAMS
1 Oil pump
2 Oil strainer
2 - 21
SPEC
CABLE ROUTING
SPEC
EBS00028
CABLE ROUTING
1 Rear brake cable
2 Throttle cable
3 Fuel tank breather hose
4 Carburetor air vent hose
5 Final gear case breather hose
6 Crankcase breather hose
7 Starter relay
8 Starting circuit cut-off relay
9 Positive battery lead
0 Wire harness
A Negative battery lead
B Rectifier/regulator
C Engine stop switch lead
(frame end)
D Battery breather hose
E Starter motor lead
F Fuel overflow hose
G Right front brake cable
2 - 22
H Left front brake cable
I Engine stop switch (frame)
CABLE ROUTING
È Route the rear brake cable to the right of the
steering stem.
É Pass the carburetor air vent hose through the hole
on the left side of the steering stem bracket and
then insert the hose between the bracket and
frame. Make sure that there is no slack or bends
in the hose. Do not route the hose over the throttle
cable.
Ê Route the final gear case breather hose and
crankcase breather hose to the right of the ignition
coil.
SPEC
Ë Align the white tape of the wire harness with the
bracket.
Ì 200 mm (7.87 in)
Í To starter motor
Î Fasten the engine stop switch lead (frame end) to
the frame with a plastic band.
Ï Pass the final gear case breather hose through
the hose guide.
Ð Pass the battery breather hose through the hole.
2 - 23
CABLE ROUTING
SPEC
Ñ Fasten the carburetor air vent hose with a plastic band. Be sure to not pinch the hose. Install the plastic
band with the buckle facing backward and the end inward.
Ò Route the cables under the frame.
Ó 45°
2 - 24
CABLE ROUTING
1 Rear brake cable
2 Wire harness
3 Ignition coil
4 Handlebar switch lead
5 Rear brake switch lead
6 Neutral indicator light lead
7 Main switch
8 C.D.I. unit
9 Fuel hose
0 Crankcase breather hose
A Final gear case breather hose
B Fuel tank breather hose
C Throttle cable
D Front brake cables
2 - 25
SPEC
CABLE ROUTING
È 80 mm (3.15 in)
É Fasten the rear brake cable, wire harness,
crankcase breather hose, and final gear case
breather hose with a plastic band. Be sure to not
pinch the hoses.
Ê Route the final gear case breather hose and
crankcase breather hose over the wire harness.
Fasten the hoses with a plastic band. Be sure to
not pinch the hoses. Pass the ends of the hoses
between the frame and bracket.
SPEC
Ë Fasten the rear brake cable and wire harness
near the ignition coil with a plastic locking tie.
Ì Do not fasten the main switch lead.
Í Fasten the crankcase breather hose and final
gear case breather hose with a plastic band.
Î Face the coupler release tabs backward.
Ï Forward
2 - 26
CABLE ROUTING
1 Rear brake switch
2 Rear brake cable
3 Left front brake cable
4 Right front brake cable
5 Throttle cable
6 Fuel tank breather hose
7 Negative battery lead
8 Main fuse
9 Positive battery lead
0 Handlebar switch
2 - 27
SPEC
CABLE ROUTING
SPEC
È Fasten the negative battery lead with the plastic holder.
É To starter motor
Ê Pass the leads through the hole.
Ë To wire harness
Ì To starter relay
Í Fasten the handlebar switch lead and rear brake switch lead with a plastic band.
Î Connect the negative battery lead to the battery so that the lead is routed to the side of the battery.
Ï Connect the positive battery lead to the battery so that the lead contacts the battery case.
2 - 28
CABLE ROUTING
1 Throttle cable
2 Fuel tank breather hose
3 Rear brake cable
4 Handlebar switch lead
5 Rear brake switch lead
6 Air filter joint
7 Neutral indicator light lead
8 Right front brake cable
9 Left front brake cable
SPEC
È Route the front brake cables to the left of the
steering stem. Route the left front brake cable to
the right of the air filter joint. Route the right front
brake cable to the left of the air filter joint.
2 - 29
INTRODUCTION/
PERIODIC MAINTENANCE/LUBRICATION
CHK
ADJ
EBS00029
PERIODIC CHECKS AND ADJUSTMENTS
INTRODUCTION
This chapter includes all information necessary to perform recommended checks and adjustments.
These preventive maintenance procedures, if followed, will ensure more reliable machine operation
and a longer service life. The need for costly overhaul work will be greatly reduced. This information
applies to machines already in service as well as to new machines that are being prepared for sale.
All service technicians should be familiar with this entire chapter.
EBS00030
PERIODIC MAINTENANCE/LUBRICATION
INITIAL
ITEM
ROUTINE
1
month
Valves*
• Check valve clearance.
• Adjust if necessary.
Cam chain*
• Check chain tension.
• Adjust if necessary.
Spark plug
• Check condition.
• Adjust gap and clean.
• Replace if necessary.
Air filter element
• Clean.
• Replace if necessary.
Carburetor*
• Check idle speed/choke lever operation.
• Adjust if necessary.
Crankcase breather
system*
• Check breather hose for cracks or damage.
• Replace if necessary.
Exhaust system*
• Check for leakage.
• Tighten if necessary.
• Replace gasket if necessary.
Spark arrester
• Clean.
Fuel line*
• Check fuel hose for cracks or damage.
• Replace if necessary.
EVERY
6
months
6
months
1
year
3
Every 20 ~ 40 hours
(more often in wet or dusty areas)
Engine oil
• Replace (warm engine before draining).
Final gear oil
• Check oil level/oil leakage.
• Replace every 12 months.
Brakes*
• Check operation.
• Adjust if necessary.
Wheels*
• Check balance/damage/runout.
• Replace if necessary.
Wheel bearings*
• Check bearing assemblies for looseness/damage.
• Replace if damaged.
Steering system*
•
•
•
•
Knuckle shafts/
steering shaft*
• Lubricate every 6 months with Lithium-soap-based
grease.
Fittings and fasteners*
• Check all chassis fittings and fasteners.
• Correct if necessary.
Battery*
• Check specific gravity.
• Check breather hose for correct routing.
• Correct if necessary.
*
3
months
Check operation.
Repair if damaged.
Check toe-in.
Adjust if necessary.
Since these items require special tools, data and technical skills, have a Yamaha dealer perform
the service.
EBS00032
WARNING
_
Indicates a potential hazard that could result in serious injury or death.
3-1
CHK
ADJ
SEAT, FENDERS AND FUEL TANK
EBS00033
SEAT, FENDERS AND FUEL TANK
SEAT AND FRONT PANEL
1
3
4
5
2
Order
1
Job/Part
Removing the seat and front panel
Seat
Q’ty
1
Remarks
Remove the parts in the order listed.
NOTE:
Pull back the seat lock lever, than pull up
on the rear of the seat.
_
2
3
4
Front panel
Fuel tank breather hose
Handlebar cover
1
1
1
NOTE:
When installing the handlebar cover,
pass the fuel tank breather hose through
the hole in the handlebar cover.
_
5
Neutral indicator light connectors
2
3-2
Disconnect.
For installation, reverse the removal procedure.
SEAT, FENDERS AND FUEL TANK
CHK
ADJ
EBS00037
FRONT FENDER
1
4
2
T.
R.
T.
R.
Order
1
2
3
4
7 Nm (0.7 m • kg, 5.1 ft • Ib)
7 Nm (0.7 m • kg, 5.1 ft • Ib)
3
Job/Part
Removing the front fender
Seat and front panel
Fuel tank top panel
Air cleaner joint clamp screw
Main switch
Front fender
Q’ty
1
1
1
1
Remarks
Remove the parts in the order listed.
Refer to “SEAT AND FRONT PANEL”.
Loosen.
For installation, reverse the removal procedure.
3-3
SEAT, FENDERS AND FUEL TANK
CHK
ADJ
EBS00039
REAR FENDER AND FOOTREST BOARDS
T.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
T.
R.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
R.
T.
R.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
T.
R.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
3
1
6
8
5
2
4
7
7
Order
1
2
3
Job/Part
Removing the rear fender and footrest boards
Seat
Front fender
Battery band
Main fuse
Negative battery lead
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “SEAT AND FRONT PANEL”.
Refer to “FRONT FENDER”.
1
1
1
Disconnect.
CAUTION:
_
First disconnect the negative lead,
then disconnect the positive lead.
4
5
Positive battery lead
Battery breather hose
1
1
3-4
Disconnect.
Disconnect.
SEAT, FENDERS AND FUEL TANK
T.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
T.
R.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
CHK
ADJ
R.
T.
R.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
T.
R.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
3
1
6
8
5
2
4
7
7
Order
6
7
8
Job/Part
Battery
Footrest board
Rear fender
Q’ty
1
2
1
Remarks
For installation, reverse the removal procedure.
3-5
SEAT, FENDERS AND FUEL TANK
CHK
ADJ
EBS00042
FUEL TANK
2
1
Order
1
Job/Part
Removing the fuel tank
Seat and front panel
Front fender
Fuel hose
Q’ty
1
Remarks
Remove the parts in the order listed.
Refer to “SEAT AND FRONT PANEL”.
Refer to “FRONT FENDER”.
Disconnect.
NOTE:
Before disconnecting the fuel hose, turn
the fuel cock to “OFF”.
_
2
Fuel tank
1
For installation, reverse the removal procedure.
3-6
ADJUSTING THE TIMING CHAIN TENSIONER
CHK
ADJ
EBS00046
ENGINE
ADJUSTING THE TIMING CHAIN
TENSIONER
1. Remove:
• C.D.I. magneto cover
• camshaft sprocket cover
Refer to “CYLINDER HEAD” in chapter 4.
2.
•
3.
•
•
Remove:
cap nut 1
Loosen:
locknut 2
adjuster 3
4. Adjust:
• timing chain tensioner
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the crankshaft counterclockwise with a
wrench.
b. Align the “T” mark 1 on the rotor with the
stationary pointer 2 on the crankcase.
When the “T” mark is aligned with the stationary pointer, the piston is at the Top Dead
Center (TDC).
NOTE:
Be sure to align the alignment mark 3 on the
camshaft sprocket with the alignment mark 4
on the cylinder head.
c. Turn the crankshaft counterclockwise to
align the camshaft sprocket alignment mark
5 and alignment tab 6 with the adjuster 7
as shown in the illustration.
d. Tighten the adjuster.
e. Install the locknut and cap nut and tighten to
specification.
T.
Locknut
7 Nm (0.7 m · kg, 5.1 ft · lb)
R.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3-7
ADJUSTING THE TIMING CHAIN TENSIONER/
ADJUSTING THE VALVE CLEARANCE
CHK
ADJ
5. Install:
• camshaft sprocket cover
• C.D.I. magneto cover
Refer to “CYLINDER HEAD” in chapter 4.
ADJUSTING THE VALVE CLEARANCE
NOTE:
• The valve clearance must be adjusted when
the engine is cool to the touch.
• Adjust the valve clearance when the piston is
at the Top Dead Center (TDC) on the compression stroke.
_
1.
•
•
•
•
Remove:
C.D.I. magneto cover
intake tappet cover
exhaust tappet cover
camshaft sprocket cover
Refer to “CYLINDER HEAD” in chapter 4.
2. Measure:
• valve clearance
Out of specification → Adjust.
Valve clearance (cold)
Intake valve
0.05 ~ 0.10 mm
(0.002 ~ 0.004 in)
Exhaust valve
0.075 ~ 0.125 mm
(0.003 ~ 0.005 in)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the crankshaft counterclockwise with a
wrench.
b. Align the “T” mark 1 on the rotor with the
stationary pointer 2 on the crankcase.
When the “T” mark is aligned with the stationary pointer, the piston is at the Top Dead
Center (TDC).
3-8
ADJUSTING THE VALVE CLEARANCE
CHK
ADJ
NOTE:
• When the piston is at the Top Dead Center
(TDC) on the compression stroke, there
should be clearance between the valve stem
tips and their respective adjusting screws.
• Be sure to align the alignment mark 3 on the
camshaft sprocket with the alignment mark
4 on the cylinder head.
• If there is no clearance, rotate the crankshaft
counterclockwise one turn.
_
c. Measure the valve clearance using a thickness gauge 5.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3. Adjust:
• valve clearance
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Loosen the locknut 1.
b. Insert a thickness gauge 2 between the
adjuster end and the valve end.
c. Turn the adjuster 3 clockwise or counterclockwise with the tappet adjusting tool 4
until the proper clearance is obtained.
Tappet adjusting tool (3 mm)
P/N. YM-08035, 90890-01311
d. Hold the adjuster to prevent it from moving
and then tighten the locknut.
T.
Locknut
7 Nm (0.7 m · kg, 5.1 ft · lb)
R.
e. Measure the valve clearance.
f. If the clearance is incorrect, repeat the
above steps until the proper clearance is
obtained.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3-9
ADJUSTING THE VALVE CLEARANCE/
ADJUSTING THE ENGINE IDLING SPEED
4.
•
•
•
•
CHK
ADJ
Install:
camshaft sprocket cover
exhaust tappet cover
intake tappet cover
C.D.I. magneto cover
Refer to “CYLINDER HEAD” in chapter 4.
EBS00051
ADJUSTING THE ENGINE IDLING SPEED
1. Start the engine and let it warm up for several minutes.
2. Attach:
• engine tachometer 1
(to the spark plug lead)
Inductive self-powered tachometer
P/N. YU-8036-B
Engine tachometer
P/N. 90890-03113
3. Measure:
• engine idling speed
Out of specification → Adjust.
Engine idling speed
1,750 ~ 1,850 r/min
4. Adjust:
• engine idling speed
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the throttle stop screw 1 in or out until
the specified idling speed is obtained.
1
Turning in
Idling speed becomes
higher.
Turning out
Idling speed becomes
lower.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
5. Detach:
• engine tachometer
3 - 10
ADJUSTING THE ENGINE IDLING SPEED/
ADJUSTING THE THROTTLE LEVER FREE PLAY
CHK
ADJ
6. Adjust:
• throttle lever free play
Refer to “ADJUSTING THE THROTTLE
LEVER FREE PLAY”.
Throttle lever free play
1.5 ~ 5.0 mm (0.06 ~ 0.20 in)
EBS00052
ADJUSTING THE THROTTLE LEVER FREE
PLAY
NOTE:
Engine idling speed should be adjusted properly before adjusting the throttle lever free
play.
_
1. Measure:
• throttle lever free play a
Out of specification → Adjust.
a
3
Throttle lever free play
1.5 ~ 5.0 mm (0.06 ~ 0.20 in)
2
1
2. Adjust:
• throttle lever free play
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Pull back the adjuster cover 1.
b. Loosen the locknut 2 on the carburetor
side.
c. Turn the adjuster 3 in or out until the correct free play is obtained.
Turning in
Free play is increased.
Turning out
Free play is decreased.
d. Tighten the locknut 2.
e. Push in the adjuster cover 1.
WARNING
_
After adjusting the free play, turn the handlebar to the right and left to make sure
that the engine idling speed does not
increase.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3 - 11
ADJUSTING THE SPEED LIMITER
CHK
ADJ
EBS00053
a
ADJUSTING THE SPEED LIMITER
The speed limiter keeps the carburetor throttle
from becoming fully-opened even when the
throttle lever is applied to the maximum position. Screwing in the adjuster stops the engine
speed from increasing.
1. Measure:
• speed limiter length a
Out of specification → Adjust.
Speed limiter length
5.0 mm (0.20 in)
2. Adjust:
• speed limiter length
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1
2
a. Loosen the locknut 1.
b. Turn the adjuster 2 in or out until the specified speed limiter length is obtained.
Turning in
Speed limiter length is
decreased.
Turning out
Speed limiter length is
increased.
c. Tighten the locknut.
WARNING
_
• Particularly for a beginner rider, the
speed limiter should be screwed in completely. Screw it out little by little as their
riding technique improves. Never remove
the speed limiter for a beginning rider.
• For proper throttle lever operation do not
turn out the adjuster more than 12.0 mm
(0.47 in). Also, always adjust the throttle
lever free play to 1.5 ~ 5.0 mm (0.06 ~
0.20 in).
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3 - 12
CHECKING THE SPARK PLUG
CHK
ADJ
EBS00057
CHECKING THE SPARK PLUG
1. Remove:
• spark plug
2. Check:
• spark plug type
Incorrect → Change.
Standard spark plug
CR7HS/NGK
3. Check:
• electrode 1
Wear/damage → Replace.
• insulator 2
Abnormal color → Replace.
Normal color is a medium-to-light tan color.
4. Clean:
• spark plug
(with a spark plug cleaner or wire brush)
5. Measure:
• spark plug gap a
Use a wire gauge or thickness gauge.
Out of specification → Regap.
Spark plug gap
0.6 ~ 0.7 mm (0.024 ~ 0.028 in)
T.
R.
6. Tighten:
• spark plug
13 Nm (1.3 m · kg, 9.4 ft · lb)
NOTE:
Before installing a spark plug, clean the gasket
surface and plug surface.
_
3 - 13
CHECKING THE IGNITION TIMING
CHK
ADJ
EBS00058
CHECKING THE IGNITION TIMING
NOTE:
Engine idling speed and throttle cable free play
should be adjusted properly before checking
the ignition timing.
_
1. Remove:
• C.D.I. magneto cover
Refer to “C.D.I. MAGNETO” in chapter 4.
2. Attach:
• engine tachometer
• timing light
(to spark plug lead)
Inductive self-powered tachometer
P/N. YU-8036-B
Engine tachometer
P/N. 90890-03113
Timing light
P/N. YM-33277-A, 90890-03141
3. Check:
• ignition timing
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a. Warm up the engine and keep it at the
specified speed.
Engine speed
1,750 ~ 1,850 r/min
b. Visually check the stationary pointer 1 to
verify it is within the required firing range 2
indicated on the rotor.
Incorrect firing range → Check the pickup
coil.
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4.
•
•
5.
•
3 - 14
Detach:
timing light
engine tachometer
Install:
C.D.I. magneto cover
Refer to “C.D.I. MAGNETO” in chapter 4.
MEASURING THE COMPRESSION PRESSURE
CHK
ADJ
EBS00061
MEASURING THE COMPRESSION
PRESSURE
NOTE:
Insufficient compression pressure will result in
a loss of performance.
_
1. Measure:
• valve clearance
Out of specification → Adjust.
Refer to “ADJUSTING THE VALVE
CLEARANCE”.
2. Start the engine, warm it up for several minutes, and then turn it off.
3. Disconnect:
• spark plug cap
4. Remove:
• spark plug
CAUTION:
_
Before removing a spark plug, use compressed air to blow away any dirt accumulated in the spark plug well to prevent it
from falling into the cylinder.
5. Attach:
• adapter
• compression gauge 1
Compression gauge
P/N. YU-33223, 90890-03081
Adapter
P/N. 90890-04082
6. Measure:
• compression pressure
Out of specification → Refer to steps (c)
and (d).
Compression pressure (at sea
level)
Minimum
1,040 kPa
(10.4 kg/cm2, 147.9 psi)
Standard
1,200 kPa
(12.0 kg/cm2, 170.6 psi)
Maximum
1,340 kPa
(13.4 kg/cm2, 190.5 psi)
3 - 15
MEASURING THE COMPRESSION PRESSURE
CHK
ADJ
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a. Set the main switch to “ON”.
b. With the throttle wide open, crank the
engine until the reading on the compression
gauge stabilizes.
WARNING
_
To prevent sparking, ground the spark plug
lead before cranking the engine.
c. If the compression pressure is above the
maximum specification, check the cylinder
head, valve surfaces and piston crown for
carbon deposits.
Carbon deposits → Eliminate.
d. If the compression pressure is below the
minimum specification, squirt a few drops of
oil into the cylinder and measure again.
Refer to the following table.
Compression pressure
(with oil applied into the cylinder)
Reading
Diagnosis
Higher than
without oil
Piston ring(s) wear
or damage →
Repair.
Same as without
oil
Piston, valves,
cylinder head
gasket or piston
possibly defective
→ Repair.
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R.
3 - 16
Install:
spark plug
Connect:
spark plug cap
T.
7.
•
8.
•
13 Nm (1.3 m · kg, 9.4 ft · lb)
CHECKING THE ENGINE OIL LEVEL
CHK
ADJ
EBS00064
CHECKING THE ENGINE OIL LEVEL
1. Place the machine on a level surface.
2. Check:
• engine oil level
Oil level should be between the maximum
a mark and minimum b mark.
Oil level low → Add oil to the proper level.
1
a
b
NOTE:
Do not screw the dipstick 1 in when checking
the oil level.
_
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a. Warm up the engine for several minutes,
and stop it, then wait at least several minutes for the oil to drain back into the crankcase.
WARNING
_
Never remove the dipstick just after high
speed operation because the heated oil
could spurt out. Wait until the oil cools
down before removing the dipstick.
b. Screw the dipstick 1 completely out, and
wipe the dipstick clean, then just rest the
dipstick in the hole.
c. Pull up the dipstick, and check the oil level
whether or not it is between maximum a
and minimum level b.
d. If the level is lower, add the oil up to the
proper level.
0°
10°
30°
50°
70°
90°
110°
130°F
Recommended oil
Follow the chart on the left.
YAMALUBE 4 (20W40) or SAE 20W40
YAMALUBE 4 (10W30) or SAE 10W30
NOTE:
Recommended oil classification:
API Service “SE”, “SF”, “SG” type or equivalent (e.g. “SF—SE—CC”, “SF—SE—SD” etc.)
_
SAE 5W30
-20°
-10°
0°
10°
20°
30°
40°
50°C
CAUTION:
_
• Do not add any chemical additives.
Engine oil also lubricates the clutch and
additives could cause clutch slippage.
• Do not allow foreign material to enter the
crankcase.
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3 - 17
CHANGING THE ENGINE OIL
CHK
ADJ
EBS00068
CHANGING THE ENGINE OIL
1. Start the engine, warm it up for several minutes, and then turn it off.
2. Place a container under the engine oil drain
bolt.
3. Remove:
• dipstick 1
• engine oil drain bolt 2
(along with the gasket)
4. Drain:
• engine oil
(completely from the crankcase)
5. Check:
• engine oil drain bolt gasket
Damage → Replace.
6. Install:
• engine oil drain bolt 1
(along with the gasket)
T.
R.
20 Nm (2.0 m · kg, 1.4 ft · lb)
7. Fill:
• crankcase
(with the specified amount of the recommended engine oil)
Quantity
Total amount
0.95 L (0.84 Imp qt, 1.00 US qt)
Periodic oil change
0.80 L (0.70 Imp qt, 0.85 US qt)
8. Install:
• dipstick
9. Start the engine, warm it up for several minutes, and then turn it off.
10.Check:
• engine
(for engine oil leaks)
11.Check:
• engine oil level
Refer to “CHECKING THE ENGINE OIL
LEVEL”.
3 - 18
CLEANING THE AIR FILTER ELEMENT
CHK
ADJ
EBS00071
CLEANING THE AIR FILTER ELEMENT
NOTE:
There is a check hose 1 at the bottom of the
air filter case. If dust and/or water collects in
this hose, clean the air filter element and air filter case.
_
1
1. Remove:
• front panel
Refer to “SEAT, FENDERS AND FUEL
TANK”.
2. Remove:
• air filter cover 1
1
3
2
1
3.
•
4.
•
•
Disconnect:
rubber band 1
Remove:
air filter element guide 2
air filter element 3
CAUTION:
_
The engine should never be run without the
air filter; excessive piston and/or cylinder
wear may result.
5. Check:
• air filter element
Damaged → Replace.
6. Clean:
• air filter element
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a. Wash the element gently, but thoroughly in
solvent.
WARNING
_
Use a cleaning solvent which is designed
to clean parts only. Never use gasoline or
low flash point solvents as they may cause
a fire or explosion.
3 - 19
CLEANING THE AIR FILTER ELEMENT/
CLEANING THE SPARK ARRESTER
CHK
ADJ
b. Squeeze the excess solvent out of the element and let it dry.
CAUTION:
_
Do not twist or wring out the element. This
could damage the foam material.
c. Apply engine oil to the element.
d. Squeeze out the excess oil.
NOTE:
The element should be wet but not dripping.
_
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7.
•
•
8.
•
9.
•
Install:
air filter element
air filter element guide
Connect:
rubber band
Install:
air filter cover
NOTE:
Make sure its sealing surface matches the
sealing surface of the case so there is no air
leak.
_
10.Install:
• front panel
Refer to “SEAT, FENDERS AND FUEL
TANK”.
CLEANING THE SPARK ARRESTER
1. Clean:
• spark arrester
1
2
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WARNING
• Select a well-ventilated area free of combustible materials.
• Always let the exhaust system cool
before performing this operation.
• Do not start the engine when removing
the tailpipe from muffler.
a. Remove the screws 1.
b. Remove the tailpipe 2 by pulling it out of
the muffler.
3 - 20
CLEANING THE SPARK ARRESTER
CHK
ADJ
c. Tap the tailpipe lightly with a soft-face hammer or suitable tool, then use a wire brush
to remove any carbon deposits from the
spark arrester portion of the tailpipe and the
inner contact surfaces of the muffler.
d. Insert the tailpipe into the muffler and align
the screw holes.
e. Insert the screw and tighten it.
T.
Screw
8 Nm (0.8 m · kg, 5.8 ft · lb)
R.
3
f. Remove the purging bolt 3.
g. Start the engine and rev it up approximately
twenty times while momentarily creating
exhaust system back pressure by blocking
the end of the muffler with a shop towel.
h. Stop the engine and allow the exhaust pipe
to cool.
i Install the purging bolt 3 and tighten it.
T.
Bolt
10 Nm (1.0 m · kg, 7.2 ft · lb)
R.
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3 - 21
CHECKING THE FRONT AND REAR BRAKE SHOES/
ADJUSTING THE FRONT BRAKE
CHK
ADJ
CHASSIS
È
EBS00079
CHECKING THE FRONT AND REAR BRAKE
SHOES
1. Operate the brake.
2. Check:
• wear indicator 1
Reaches the wear limit line 2 → Replace
the brake shoes as a set.
Refer to “FRONT AND REAR BRAKES” in
chapter 7.
É
È Front brake
É Rear brake
EBS00082
ADJUSTING THE FRONT BRAKE
NOTE:
Before adjusting the front brake, the front
brake linings should be checked.
_
CAUTION:
_
Proper lever free play is essential to avoid
excessive brake drag.
1. Measure:
• front brake lever free play a
Out of specification → Adjust.
Front brake lever free play
10 ~ 12 mm (0.39 ~ 0.47 in)
2. Adjust:
• front brake lever free play
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b
a. Loosen the locknuts 1.
b. Turn the adjusters 2 in or out until the
specified front brake lever free play is
obtained.
NOTE:
Make sure that the difference between clearances b and c is less than 2 mm when the
front brake lever is squeezed.
c
c. Tighten the locknuts.
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3 - 22
ADJUSTING THE REAR BRAKE
CHK
ADJ
EBS00084
ADJUSTING THE REAR BRAKE
NOTE:
Before adjusting the rear brake, the rear brake
linings should be checked.
_
CAUTION:
_
Proper lever free play is essential to avoid
excessive brake drag.
1. Place the machine on a level surface.
2. Measure:
• rear brake lever free play a
Out of specification → Adjust.
Rear brake lever free play
7 ~ 10 mm (0.28 ~ 0.39 in)
3. Adjust:
• brake lever free play
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First step:
a. Loosen the locknut 1 and fully turn in the
adjuster 2 (lever side).
b. Turn the adjuster 3 in or out until the specified rear brake lever free play is obtained
(drum side).
c. Tighten the locknut.
NOTE:
If the free play cannot be adjusted here, adjust
if at the lever side of the cable.
Second step:
a. Loosen the locknut 1.
b. Turn the adjuster 2 in or out until the specified rear brake lever free play is obtained
(lever side).
c. Tighten the locknut.
WARNING
_
After this adjustment is performed. block
the rear of the machine off the ground, and
spin the rear wheels to ensure there is no
brake drag. If any brake drag is noticed,
perform the above steps again.
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3 - 23
CHECKING THE FINAL GEAR OIL LEVEL/
CHANGING THE FINAL GEAR OIL
CHK
ADJ
EBS00101
1
a
b
CHECKING THE FINAL GEAR OIL LEVEL
1. Place the machine on a level surface.
2. Remove:
• dipstick 1
3. Check:
• final gear oil level
Oil level should be between the maximum
a and minimum b marks.
Oil level low → Add oil to the proper level.
Recommended oil
SAE80 API “GL-4” Hypoid gear
oil
CAUTION:
_
Take care not allow foreign material to
enter the final gear case.
4. Install:
• dipstick
EBS00102
CHANGING THE FINAL GEAR OIL
1. Place the machine on a level surface.
2. Place a receptacle under the final gear
case.
3. Remove:
• dipstick 1
• final gear oil drain plug 2
4. Drain:
• final gear oil
5. Install:
• final gear oil drain plug
T.
R.
23 Nm (2.3 m · kg, 17 ft · lb)
NOTE:
Check the gasket (drain plug). If it is damaged,
replace it with a new one.
_
3 - 24
CHANGING THE FINAL GEAR OIL/
CHECKING THE SWINGARM DUST BOOT
CHK
ADJ
6. Fill:
• final gear case
Total amount
0.12 L (0.11 Imp qt, 0.13 US qt)
Recommended oil
SAE80 API “GL-4” Hypoid gear
oil
CAUTION:
_
Take care not to allow foreign material to
enter the final gear case.
7. Check:
• final gear oil level
Refer to “CHECKING THE FINAL GEAR
OIL LEVEL”.
8. Install:
• dipstick
EBS00105
CHECKING THE SWINGARM DUST BOOT
1. Remove:
• C.D.I. magneto cover
Refer to “C.D.I. MAGNETO” in chapter 4.
2. Check:
• dust boot 1
Damage → Replace.
Refer to “REAR SHOCK ABSORBER AND
REAR SWINGARM” in chapter 7.
3. Install:
• C.D.I. magneto cover
Refer to “C.D.I. MAGNETO” in chapter 4.
3 - 25
CHECKING THE STEERING SYSTEM
CHK
ADJ
EBS00107
CHECKING THE STEERING SYSTEM
1. Place the machine on a level surface.
2. Check:
• steering shaft bushings and bearings
Move the handlebar up and down, and/or
back and forth.
Excessive play → Replace the steering
shaft bushings and or bearings.
Refer to “STEERING SYSTEM” in chapter
7.
3. Check:
• tie-rod ends
Turn the handlebar to the left and/or right
until it stops completely, then slightly move
the handlebar from left to right.
Tie-rod end has any vertical play →
Replace the tie-rod end(s).
Refer to “STEERING SYSTEM” in chapter
7.
4. Raise the front end of the machine so that
there is no weight on the front wheels.
5. Check:
• knuckles and/or wheel bearings
Move the wheels laterally back and forth.
Excessive free play → Replace the following parts.
1) Wheel bearings
2) Bushings 1
3) Thrust covers 2
4) Knuckle shafts 3
5) Spacers 4
6) Cotter pins 5
Refer to “FRONT AND REAR WHEELS”
and “STEERING SYSTEM” in chapter 7.
3 - 26
ADJUSTING THE TOE-IN
CHK
ADJ
EBS00108
ADJUSTING THE TOE-IN
1. Place the machine on a level surface.
2. Measure:
• toe-in
Out of specification → Adjust.
Toe-in
0 ~ 10 mm (0 ~ 0.39 in)
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NOTE:
Before measuring the toe-in, make sure that
the tire pressure is correct.
_
a. Mark both front tire tread centers.
b. Raise the front end of the machine so that
there is no weight on the front tires.
c. Face the handlebar straight ahead.
d. Measure the width È between the marks.
e. Rotate the front tires 180° until the marks
are exactly opposite one another.
f. Measure the width É between the marks.
g. Calculate the toe-in using the formula given
below.
Toe-in = É – È
h. If the toe-in is incorrect, adjust it.
Ê Forward
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3. Adjust:
• toe-in
WARNING
_
• Be sure that both tie-rods are turned the
same amount. If not, the machine will drift
right or left even though the handlebar is
positioned straight. This may lead to mishandling and an accident.
• After setting the toe-in to specification,
run the machine slowly for some distance
with both hands lightly holding the handlebar and check that the handlebar
responds correctly. If not, turn either the
right or left tie-rod within the toe-in specification.
3 - 27
ADJUSTING THE TOE-IN/CHECKING THE FRONT AND
REAR SHOCK ABSORBERS
CHK
ADJ
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a. Mark both tie-rods ends.
This reference point will be needed during
adjustment.
b. Loosen the locknuts (tie-rod end) 1 of both
tie-rods.
c. The same number of turns should be given
to both the right and left tie-rods 2 until the
specified toe-in is obtained. This is to keep
the length of the rods the same.
d. Tighten the rod end locknuts of both tierods.
T.
Locknut (rod end)
15 Nm (1.5 m · kg, 11 ft · lb)
R.
NOTE:
Adjust the rod ends so that A and B are equal.
_
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EBS00109
È
É
CHECKING THE FRONT AND REAR SHOCK
ABSORBERS
1. Place the machine on a level surface.
2. Check:
• damper rod 1
Scratch/damage → Replace as a set.
• oil leakage
Excessive oil leakage → Replace as a set.
Refer to “FRONT SHOCK ABSORBER
ASSEMBLIES AND FRONT SWINGARM”
and “REAR SHOCK ABSORBER AND
REAR SWINGARM” in chapter 7.
3. Check:
• operation
Pump the shock absorbers up and down for
several times.
Unsmooth operation → Replace as a set.
Refer to “FRONT SHOCK ABSORBER
ASSEMBLIES AND FRONT SWINGARM”
and “REAR SHOCK ABSORBER AND
REAR SWINGARM” in chapter 7.
È Front shock absorber
É Rear shock absorber
3 - 28
CHECKING THE TIRES
CHK
ADJ
EBS00114
CHECKING THE TIRES
WARNING
_
This model is equipped with low pressure
tires. It is important that they be inflated
correctly and maintained at the proper
pressures.
• TIRE CHARACTERISTICS
1) Tire characteristics influence the handling of ATVs. The tires listed below
have been approved by Yamaha Motor
Co., Ltd. for this model. If other tire combinations are used, they can adversely
affect your machine’s handling characteristics and are therefore not recommended.
Manufacturer
Size
Type
Front
DUNLOP
AT16 ×
7-7
KT145
Rear
DUNLOP
AT16 ×
8-7
KT145
• TIRE PRESSURE
1) Recommended tire pressure
Front 20 kPa (0.20 kgf/cm2, 2.9 psi)
Rear 20 kPa (0.20 kgf/cm2, 2.9 psi)
2) Tire pressure below the minimum specification could cause the tire to dislodge
from the rim under severe riding conditions.
The following are minimums:
Front 17 kPa (0.17 kgf/cm2, 2.5 psi)
Rear 17 kPa (0.17 kgf/cm2, 2.5 psi)
3) Use no more than
Front 250 kPa (2.5 kgf/cm2, 36 psi)
Rear 250 kPa (2.5 kgf/cm2, 36 psi)
when seating the tire beads. Higher
pressures may cause the tire to burst.
Inflate the tires slowly and carefully.
Fast inflation could cause the tire to
burst.
• MAXIMUM LOADING LIMIT
Vehicle load limits: 40 kg (88 lb)
*Total weight of the cargo, trailer hitch
vertical load, rider, and accessories.
3 - 29
CHECKING THE TIRES
CHK
ADJ
1. Measure:
• tire pressure
Out of specification → Adjust.
NOTE:
• The low-pressure tire gauge 1 is included
as standard equipment.
• If dust or the like is stuck to this gauge, it will
not provide the correct readings. Therefore,
take two measurements of the tire’s pressure
and use the second reading.
_
Cold tire
pressure
Front
Rear
Standard
20 kPa
20 kPa
(0.20 kgf/cm2, (0.20 kgf/cm2,
2.9 psi)
2.9 psi)
Minimum
17 kPa
17 kPa
(0.17 kgf/cm2, (0.17 kgf/cm2,
2.5 psi)
2.5 psi)
Maximum
23 kPa
23 kPa
2
(0.23 kgf/cm , (0.23 kgf/cm2,
3.3 psi)
3.3 psi)
WARNING
_
Uneven or improper tire pressure may
adversely affect the handling of this
machine and may cause loss of control.
• Maintain proper tire pressures.
• Set tire pressures when the tires are cold.
• Tire pressures must be equal in both front
tires and equal in both rear tires.
3 - 30
CHECKING THE TIRES/
CHECKING THE WHEELS
CHK
ADJ
2. Check:
• tire surfaces
Wear/damage → Replace.
Tire wear limit a
Front and rear: 3 mm (0.12 in)
WARNING
_
It is dangerous to ride with a worn-out tire.
When tire wear is out of specification,
replace the tire immediately.
EBS00116
CHECKING THE WHEELS
1. Check:
• wheel 1
Damage/bends → Replace.
NOTE:
Always balance the wheel when a tire or wheel
has been changed or replaced.
_
WARNING
_
• Never attempt even small repairs to the
wheel.
• Ride conservatively after installing a tire
to allow it to seat itself properly on the
rim.
3 - 31
CHECKING AND LUBRICATING THE CABLES/LUBRICATING THE
LEVERS, STEERING SHAFT AND STEERING KNUCKLES
CHK
ADJ
EBS00117
CHECKING AND LUBRICATING THE
CABLES
WARNING
_
A damaged cable sheath may cause corrosion and interfere with the cable movement. An unsafe condition may result so
replace a damaged cable as soon as possible.
1. Check:
• cable sheath
Damage → Replace.
2. Check:
• cable operation
Unsmooth operation → Lubricate or
replace.
Recommended lubricant
Lithium-soap-base grease
NOTE:
Hold the cable end up and apply several drops
of lubricant to the cable.
_
EBS00118
LUBRICATING THE LEVERS, STEERING
SHAFT AND STEERING KNUCKLES
Lubricate the pivoting point and metal-to-metal
moving parts of the levers, steering shaft and
steering knuckles.
Recommended lubricant
Lithium-soap-base grease
3 - 32
CHECKING AND CHARGING THE BATTERY
CHK
ADJ
EBS00119
ELECTRICAL SYSTEM
CHECKING AND CHARGING THE
BATTERY
WARNING
_
Batteries generate explosive hydrogen gas
and contain electrolyte which is made of
poisonous and highly caustic sulfuric acid.
Therefore, always follow these preventive
measures:
• Wear protective eye gear when handling
or working near batteries.
• Charge batteries in a well-ventilated area.
• Keep batteries away from fire, sparks or
open flames (e.g., welding equipment,
lighted cigarettes).
• DO NOT SMOKE when charging or handling batteries.
• KEEP BATTERIES AND ELECTROLYTE
OUT OF REACH OF CHILDREN.
• Avoid bodily contact with electrolyte as it
can cause severe burns or permanent eye
injury.
FIRST AID IN CASE OF BODILY CONTACT:
EXTERNAL
• Skin — Wash with water.
• Eyes — Flush with water for 15 minutes
and get immediate medical attention.
INTERNAL
• Drink large quantities of water or milk followed with milk of magnesia, beaten egg
or vegetable oil. Get immediate medical
attention.
1. Remove:
• seat
• battery band
Refer to “SEAT, FENDERS AND FUEL
TANK”.
2. Disconnect:
• battery leads
(from the battery terminals)
• battery breather hose
CAUTION:
_
First, disconnect the negative battery lead
1, and then the positive lead 2.
3 - 33
CHECKING AND CHARGING THE BATTERY
b
a
3.
•
4.
•
CHK
ADJ
Remove:
battery
Check:
electrolyte level
The electrolyte level should be between the
minimum level mark a and the maximum
level mark b.
Below the minimum level mark → Add distilled water to the proper level.
CAUTION:
_
Add only distilled water. Tap water contains minerals which are harmful to the battery.
5. Check:
• specific gravity
Less than 1.280 → Recharge the battery.
Specific gravity
1.280 at 20 °C (68 °F)
6. Charge:
• battery
Battery charging amperage and
time
7 amps/10 hrs
WARNING
_
Do not quick charge a battery.
CAUTION:
_
• Loosen the battery sealing caps.
• Make sure the battery breather hose and
battery vent are free of obstructions.
• To ensure maximum performance, always
charge a new battery before using it.
3 - 34
CHECKING AND CHARGING THE BATTERY
CHK
ADJ
• Do not use a high-rate battery charger.
They force a high-amperage current into
the battery quickly and can cause battery
overheating and battery plate damage.
• If it is impossible to regulate the charging
current on the battery charger, be careful
not to overcharge the battery.
• When charging a battery, be sure to
remove it from the machine. (If charging
has to be done with the battery mounted
on the machine, disconnect the negative
lead from the battery terminal.)
• To reduce the chance of sparks, do not
plug in the battery charger until the battery charger leads are connected to the
battery.
• Before removing the battery charger lead
clips from the battery terminals, be sure
to turn off the battery charger.
• Make sure the battery charger lead clips
are in full contact with the battery terminal and that they are not shorted. A corroded battery charger lead clip may
generate heat in the contact area and a
weak clip spring may cause sparks.
• If the battery becomes hot to the touch at
any time during the charging process,
disconnect the battery charger and let the
battery cool before reconnecting it. Hot
batteries can explode!
NOTE:
Replace the battery whenever:
• battery voltage does not rise to specification
or bubbles fail to rise during charging,
• sulfation of one or more battery cells occurs
(as indicated by the battery plates turning
white or material accumulating in the bottom
of the battery cell),
• specific gravity readings after a long, slow
charge indicate that one battery cell’s charge
is lower than the rest,
• warpage or buckling of the battery plates or
insulators is evident.
_
3 - 35
CHECKING AND CHARGING THE BATTERY
CHK
ADJ
7. Check:
• battery breather hose and battery vent
Obstruction → Clean.
Damage → Replace.
8. Install:
• battery
9. Connect:
• battery breather hose 1
CAUTION:
_
When checking the battery, make sure the
battery breather hose is properly installed
and routed correctly. If the battery breather
hose is positioned so as to allow electrolyte or hydrogen gas from the battery to
contact the frame, the machine and its finish may be damaged.
NOTE:
Refer to “CABLE ROUTING” in chapter 2.
10.Check:
• battery terminals
Dirt → Clean with a wire brush.
Loose connection → Connect properly.
11.Connect:
• battery leads
(to the battery terminals)
CAUTION:
_
First, connect the positive battery lead 1,
and then the negative battery lead 2.
12.Lubricate:
• battery terminals
Recommended lubricant
Dielectric grease
13.Install:
• battery band
• seat
Refer to “SEAT, FENDERS AND FUEL
TANK”.
3 - 36
CHECKING THE FUSE
CHK
ADJ
EBS00121
CHECKING THE FUSE
CAUTION:
_
To avoid a short circuit, always set the
main switch to “OFF” when checking or
replacing a fuse.
1. Remove:
• seat
Refer to “SEAT, FENDERS AND FUEL
TANK”.
• fuse holder 1
2. Check:
• fuse
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester to the fuse and
check the continuity.
NOTE:
Set the pocket tester selector to “Ω × 1”.
_
Pocket tester
P/N. YU-03112-C, 90890-03112
b. If the pocket tester indicates “∞”, replace
the fuse.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3. Replace:
• blown fuse
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Set the main switch to “OFF”.
b. Install a new fuse of the correct amperage.
c. Set on the switches to verify if the electrical
circuit is operational.
3 - 37
CHECKING THE FUSE
CHK
ADJ
d. If the fuse immediately blows again, check
the electrical circuit.
Items
Amperage
rating
Q’ty
Main
5A
1
Reserve
5A
1
WARNING
_
Never use a fuse with an amperage rating
other than that specified. Improvising or
using a fuse with the wrong amperage rating may cause extensive damage to the
electrical system, cause the ignition systems to malfunction and could possibly
cause a fire.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4. Install:
• seat
Refer to “SEAT, FENDERS AND FUEL
TANK”.
3 - 38
ENGINE
ENG
EBS00198
ENGINE
ENGINE
EXHAUST PIPE/MUFFLER, BREATHER HOSE AND LEADS
T.
R.
25 Nm (2.5 m • kg, 18 ft • Ib)
1
5
4
3
2
T.
R.
Order
1
2
3
4
5
4
10 Nm (1.0 m • kg, 7.2 ft • Ib)
Job/Part
Removing the exhaust pipe/muffler,
breather hose and leads
Rear fender
Exhaust pipe/muffler
Exhaust pipe gasket
Spark plug lead
C.D.I. magneto coupler
Crankcase breather hose
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “SEAT, FENDERS AND FUEL
TANK” in chapter 3.
1
1
1
2
1
For installation, reverse the removal procedure.
4-1
ENG
ENGINE
EBS00205
ENGINE MOUNTING BOLTS
T.
R.
33 Nm (3.3 m • kg, 24 ft • Ib)
3
3
2
4
1
5
2
1
T.
R.
Order
1
2
33 Nm (3.3 m • kg, 24 ft • Ib)
Job/Part
Removing the engine mounting
bolts
Carburetor
Starter motor
C.D.I. magneto cover
Metal clamp
Lower engine mounting nut/bolt
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “CARBURETOR” in chapter 5.
Refer to “ELECTRIC STARTING SYSTEM” in chapter 8.
Refer to “C.D.I. MAGNETO”.
2
1/1
CAUTION:
_
Install all of the bolts/nuts and then
tighten them to full torque specifications.
Refer to “INSTALLING THE ENGINE”.
4-2
ENG
ENGINE
T.
R.
33 Nm (3.3 m • kg, 24 ft • Ib)
3
3
2
4
1
5
2
1
T.
R.
Order
3
4
5
33 Nm (3.3 m • kg, 24 ft • Ib)
Job/Part
Upper engine mounting nut/bolt
Engine assembly
Dust boot
Q’ty
Remarks
1/1
Refer to “INSTALLING THE ENGINE”.
1
1
Refer to “REMOVING THE ENGINE” and
“INSTALLING THE ENGINE”.
For installation, reverse the removal procedure.
4-3
ENGINE
ENG
REMOVING THE ENGINE
1. Remove:
• metal clamps
NOTE:
After removing the metal clamps, slide the dust
boot 1 towards the swingarm.
1
EBS00207
INSTALLING THE ENGINE
1. Install:
• dust boot 1
1
NOTE:
Before mounting the engine assembly, install
the dust boot onto the middle driven gear bearing housing.
2. Install:
• upper engine mounting bolt/nut 1
• lower engine mounting bolt/nut 2
1
NOTE:
Do not fully tighten the bolts and nuts.
_
3. Tighten:
• upper engine mounting nut 1
2
T.
R.
33 Nm (3.3 m · kg, 24 ft · lb)
• lower engine mounting nut 2
T.
R.
4-4
33 Nm (3.3 m · kg, 24 ft · lb)
CYLINDER HEAD
ENG
EBS00218
CYLINDER HEAD
Order
1
2
3
4
5
6
7
8
9
10
Job/Part
Removing the cylinder head
Carburetor assembly
Exhaust pipe/muffler
C.D.I. magneto cover
Spark plug lead
Spark plug
Camshaft sprocket cover
Intake tappet cover
Exhaust tappet cover
Timing chain tension adjuster
Timing chain tensioner assembly
Camshaft sprocket
Cylinder head
Intake side timing chain guide
Q’ty
1
1
1
1
1
1
1
1
1
1
4-5
Remarks
Remove the parts in the order listed.
Refer to “CARBURETOR” in chapter 5.
Refer to “ENGINE”.
Refer to “C.D.I. MAGNETO”.
Refer to “REMOVING THE CYLINDER
HEAD” and “INSTALLING THE CYLINDER HEAD”.
CYLINDER HEAD
Order
11
12
13
Job/Part
Exhaust side timing chain guide
Cylinder head gasket
Dowel pin
Q’ty
1
1
2
ENG
Remarks
For installation, reverse the removal procedure.
4-6
CYLINDER HEAD
ENG
EBS00220
REMOVING THE CYLINDER HEAD
1. Align:
• “T” mark on the rotor
(with the stationary pointer on the crankcase)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
4
a. Turn the crankshaft counterclockwise with a
wrench.
b. Align the “T” mark 1 on the rotor with the
stationary pointer 2 on the crankcase.
When the “T” mark is aligned with the stationary pointer, the piston is at Top Dead
Center (TDC).
3
NOTE:
TDC on compression stroke check:
• Both rocker arms must have a valve clearance when the camshaft sprocket alignment
mark 3 is aligned with the cylinder head
alignment mark 4.
• If not, give the crankshaft one counterclockwise turn to meet the above condition.
_
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Loosen:
• camshaft sprocket bolt 1
Use the sheave holder 2 to hold the rotor.
NOTE:
Do not allow the sheave holder to touch the
projection on the rotor.
1
Sheave holder
P/N. YS-01880-A, 90890-01701
2
3.
•
•
•
Remove:
timing chain tension adjuster
timing chain tensioner assembly
camshaft sprocket
NOTE:
• Fasten a safety wire to the timing chain to
prevent it from falling into the crankcase.
• When removing the camshaft sprocket, it is
not necessary to separate the timing chain.
_
4-7
CYLINDER HEAD
4.
•
•
•
ENG
Remove:
bolts
nuts
cylinder head 1
NOTE:
Working in a crisscross pattern, loosen each
nut 1/4 of a turn.
_
1
EBS00224
CHECKING THE CAMSHAFT SPROCKET
1. Check:
• camshaft sprocket
Wear/damage → Replace the camshaft
sprocket and timing chain as a set.
1 1/4 of a tooth
2 Correct
3 Roller
4 Sprocket
2
CHECKING THE TAPPET COVERS AND
CAMSHAFT SPROCKET COVER
1. Check:
• tappet covers 1
• camshaft sprocket cover 2
• O-rings
Cracks/damage → Replace.
1
EBS00226
CHECKING THE TIMING CHAIN GUIDES
1. Check:
• intake side timing chain guide 1
• exhaust side timing chain guide 2
Wear/damage → Replace.
EBS00228
CHECKING THE TIMING CHAIN
TENSIONER ASSEMBLY
1. Check:
• chain tensioner assembly
Wear/damage → Replace.
4-8
CYLINDER HEAD
ENG
EBS00230
CHECKING THE CYLINDER HEAD
1. Eliminate:
• combustion chamber carbon deposits
(with a rounded scraper)
NOTE:
Do not use a sharp instrument to avoid damaging or scratching:
• spark plug bore threads
• valve seats
_
2. Check:
• cylinder head
Damage/scratches → Replace.
• cylinder head water jacket
Mineral deposits/rust → Eliminate.
3. Measure:
• cylinder head warpage
Out of specification → Resurface the cylinder head.
Maximum cylinder head warpage
0.05 mm (0.002 in)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Place a straightedge and a thickness gauge
across the cylinder head.
b. Measure the warpage.
c. If the limit is exceeded, resurface the cylinder head as follows.
d. Place a 400 ~ 600 grit wet sandpaper on
the surface plate and resurface the cylinder
head using a figure-eight sanding pattern.
NOTE:
To ensure an even surface, rotate the cylinder
head several times.
_
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4-9
CYLINDER HEAD
ENG
EBS00233
INSTALLING THE CYLINDER HEAD
1. Install:
• cylinder head 1
• nuts
• bolts
NOTE:
Tighten the nuts in two stages and a crisscross
pattern.
_
1
2. Install:
• camshaft sprocket
2
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
1
a. Rotate the camshaft to align the camshaft
groove 1 opposite to the cylinder head
alignment mark 2 as shown.
b. Turn the crankshaft counterclockwise with a
wrench.
c. Align the “T” mark 3 on the rotor with the
stationary pointer 4 on the crankcase.
When the “T” mark is aligned with the stationary pointer, the piston is at the Top Dead
Center (TDC).
CAUTION:
_
Do not turn the crankshaft during the camshaft sprocket installation.
2
5
d. Place the timing chain onto the camshaft
sprocket.
e. Install the camshaft sprocket onto the camshaft and finger tighten the sprocket bolt.
NOTE:
Be sure to align the alignment mark 5 on the
camshaft sprocket with the alignment mark 2
on the cylinder head.
_
f. Force the camshaft clockwise and counterclockwise to remove timing chain slack.
g. Insert a screwdriver into the timing chain
tensioner hole and push the timing chain
guide inward.
h. While pushing the timing chain guide, be
sure that the camshaft sprocket alignment
mark 5 is aligned with the cylinder head
alignment mark 2.
4 - 10
CYLINDER HEAD
ENG
i. If the marks are aligned, temporarily tighten
the camshaft sprocket bolt. If the marks are
not aligned, change the meshing position of
the camshaft sprocket and timing chain.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2
3. Install:
• timing chain tensioner assembly
3
T.
R.
18 Nm (1.8 m · kg, 13 ft · lb)
• timing chain tension adjuster
1
NOTE:
• Align the timing chain tensioner rod groove
1 with the timing chain tensioner straight
plug projection 2.
• The flat surface 3 of the timing chain tensioner rod should face towards the adjuster
threaded hole 4.
4
WARNING
_
Always use a new gasket.
4. Adjust:
• timing chain tensioner
Refer to “ADJUSTING THE TIMING CHAIN
TENSIONER” in chapter 3.
5. Tighten:
• camshaft sprocket bolt 1
T.
R.
20 Nm (2.0 m · kg, 14 ft · lb)
NOTE:
• Use the sheave holder 2 to hold the rotor.
• Do not allow the sheave holder to touch the
projection on the rotor.
_
1
2
Sheave holder
P/N. YS-01880-A, 90890-01701
6. Check:
• camshaft sprocket alignment mark
• rotor “T” mark
Out of alignment → Adjust.
4 - 11
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
EBS00235
CAMSHAFT, ROCKER ARMS AND VALVES
Order
1
2
3
4
5
6
7
8
9
10
11
12
Job/Part
Removing the camshaft, rocker
arms and valves
Cylinder head
Intake manifold
Rocker arm shaft
Rocker arm
Adjuster
Camshaft
Valve cotter
Valve spring retainer
Valve spring
Intake valve
Exhaust valve
Valve stem seal
Valve spring seat
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “CYLINDER HEAD”.
1
2
2
2
1
4
2
2
1
1
2
2
4 - 12
Refer to “REMOVING THE ROCKER
ARMS AND CAMSHAFT” and
“INSTALLING THE CAMSHAFT AND
ROCKER ARMS”.
Refer to “REMOVING THE VALVES
AND VALVE SPRINGS” and “INSTALLING THE VALVES AND VALVE
SPRINGS”.
CAMSHAFT, ROCKER ARMS AND VALVES
Order
13
Job/Part
Valve guide
Q’ty
2
ENG
Remarks
For installation, reverse the removal procedure.
4 - 13
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
EBS00237
REMOVING THE ROCKER ARMS AND
CAMSHAFT
1. Loosen:
• locknuts
• adjusters
2. Remove:
• intake rocker arm shaft
• exhaust rocker arm shaft
• intake rocker arm
• exhaust rocker arm
NOTE:
Remove the rocker arm shafts with the slide
hammer bolt 1 and weight 2.
_
Slide hammer set
P/N. YU-01083-A
Slide hammer bolt (M8)
P/N. 90890-01085
Weight
P/N. 90890-01084
3. Remove:
• camshaft 1
NOTE:
Screw a M8 bolt 2 into the threaded end of
the camshaft and then pull out the camshaft.
_
2
1
EBS00238
REMOVING THE VALVES AND VALVE
SPRINGS
1. Check:
• valve sealing
Leakage at the valve seat → Check the
valve face, valve seat and valve seat width.
Refer to “CHECKING THE VALVES AND
VALVE SPRINGS”.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
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.
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4 - 14
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
2. Remove:
• valve cotters
NOTE:
Attach a valve spring compressor 1 and
attachment 2 between the valve spring
retainer and the cylinder head to remove the
valve cotters.
_
2
1
Valve spring compressor
P/N. YM-04019, 90890-04019
Valve spring compressor attachment
P/N. YM-04108, 90890-04108
EBS00223
CHECKING THE CAMSHAFT
1. Check:
• cam lobes
Pitting/scratches/blue discoloration →
Replace.
2. Measure:
• cam lobe dimensions a and b
Out of specification → Replace.
Camshaft lobe limit
Intake
a 25.200 mm (0.9921 in)
b 20.894 mm (0.8226 in)
Exhaust
a 25.201 mm (0.9922 in)
b 20.921 mm (0.8237 in)
EBS00239
CHECKING THE ROCKER ARMS AND
ROCKER ARM SHAFTS
The following procedure applies to all of the
rocker arms and rocker arm shafts.
1. Check:
• rocker arm
Damage/wear → Replace.
4 - 15
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
2. Check:
• rocker arm shaft
Blue discoloration/excessive wear/pitting/
scratches → Replace or check the lubrication system.
3. Check:
• camshaft lobe
Excessive wear → Replace the camshaft.
4. Measure:
• rocker arm inside diameter a
Out of specification → Replace.
Rocker arm inside diameter
10.000 ~ 10.015 mm
(0.3937 ~ 0.3943 in)
5. Measure:
• rocker arm shaft outside diameter a
Out of specification → Replace.
Rocker arm shaft outside diameter
9.981 ~ 9.991 mm
(0.3930 ~ 0.3933 in)
6. Calculate:
• rocker-arm-to-rocker-arm-shaft clearance
NOTE:
Calculate the clearance by subtracting the
rocker arm shaft outside diameter from the
rocker arm inside diameter.
_
Above 0.08 mm (0.0031 in) → Replace the
defective part(s).
Rocker-arm-to-rocker-arm-shaft
clearance
0.009 ~ 0.034 mm
(0.0004 ~ 0.0013 in)
<Limit>: 0.08 mm (0.0031 in)
4 - 16
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
EBS00240
CHECKING THE VALVES AND VALVE
SPRINGS
1. Measure:
• stem-to-guide clearance
Stem-to-guide clearance =
valve guide inside diameter a –
valve stem diameter b
Out of specification → Replace the valve
guide.
Stem-to-guide clearance
Intake
0.010 ~ 0.037 mm
(0.0004 ~ 0.0015 in)
<Limit>: 0.08 mm (0.0031 in)
Exhaust
0.025 ~ 0.052 mm
(0.0010 ~ 0.0020 in)
<Limit>: 0.10 mm (0.0039 in)
2. Replace:
• valve guide
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
NOTE:
To ease guide removal, installation and to
maintain correct fit, heat the cylinder head to
100 °C (212 °F) in an oven.
_
a. Remove the valve guide using a valve guide
remover 1.
b. Install the new valve guide using a valve
guide remover 1 and valve guide installer
2.
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 (5 mm)
P/N. YM-04097, 90890-04097
Valve guide installer (5 mm)
P/N. YM-04098, 90890-04098
Valve guide reamer (5 mm)
P/N. 90890-04099
NOTE:
After replacing the valve guide reface the valve
seat.
_
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4 - 17
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
3. Check:
• valve face
Pitting/wear → Grind the face.
• valve stem end
Mushroom shape or diameter larger than
the body of the stem → Replace.
4. Measure:
• margin thickness a
Out of specification → Replace.
Margin thickness
Intake
0.5 ~ 0.9 mm
(0.0197 ~ 0.0354 in)
<Limit>: 1.6 mm (0.0630 in)
Exhaust
0.6 ~ 1.0 mm
(0.0236 ~ 0.0394 in)
<Limit>: 1.6 mm (0.0630 in)
5. Measure:
• runout (valve stem)
Out of specification → Replace.
Runout limit
0.02 mm (0.0008 in)
NOTE:
• 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. Check:
• valve seats
Pitting/wear → Reface the valve seat.
4 - 18
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
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 (0.063 in)
Exhaust
0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)
<Limit>: 1.6 mm (0.063 in)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Apply Mechanic’s blueing dye (Dykem) b to
the valve face.
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.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
9. Lap:
• valve face
• valve seat
NOTE:
After refacing the valve seat or replacing the
valve and valve guide, the valve seat and
valve face should be lapped.
_
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Apply a coarse lapping compound to the
valve face.
CAUTION:
_
Do not let the compound enter the gap
between the valve stem and the guide.
4 - 19
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
b. Apply molybdenum disulfide oil to the valve
stem.
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.
NOTE:
For best lapping results, lightly tap the valve
seat while rotating the valve back and forth
between your hands.
_
e. Apply a fine lapping compound to the valve
face and repeat the above steps.
NOTE:
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.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
10.Measure:
• valve spring free length a
Out of specification → Replace.
Valve spring free length
32 mm (1.26 in)
<Limit>: 30.4 mm (1.20 in)
11.Measure:
• compressed spring force a
Out of specification → Replace.
b Installed length
Compressed spring force
136 ~ 158 N at 24.6 mm
(13.87 ~ 16.11 kg,
30.57 ~ 35.52 lb at 0.97 in)
4 - 20
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
12.Measure:
• spring tilt a
Out of specification → Replace.
Spring tilt limit
Inner
2.5°/1.4 mm (2.5°/0.06 in)
EBS00241
INSTALLING THE VALVES AND VALVE
SPRINGS
1. Apply:
• molybdenum disulfide oil
(onto the valve stem and valve stem seal)
2. Install:
• valve spring seats
• valve stem seals New
• valves
• valve springs
• valve spring retainers
NOTE:
Install the valve springs with the larger pitch a
facing upwards.
_
b Smaller pitch
3. Install:
• valve cotters
NOTE:
Install the valve cotters while compressing the
valve spring with the valve spring compressor
1 and attachment 2.
_
2
1
Valve spring compressor
P/N. YM-04019, 90890-04019
Valve spring compressor attachment
P/N. YM-04108, 90890-04108
4. To secure the valve cotters onto the valve
stem, lightly tap the valve tip with a piece of
wood.
CAUTION:
_
Hitting the valve tip with excessive force
could damage the valve.
4 - 21
CAMSHAFT, ROCKER ARMS AND VALVES
ENG
EBS00243
1
INSTALLING THE CAMSHAFT AND
ROCKER ARMS
1. Install:
• camshaft 1
NOTE:
Install the camshaft groove a facing down.
_
a
2. Apply:
• engine oil
(onto the rocker arm shafts)
3. Install:
• rocker arms 1
• rocker arm shafts
1
NOTE:
Use a slide hammer bolt 2 to install the rocker
arm shaft.
_
2
4 - 22
CYLINDER AND PISTON
ENG
EBS00245
CYLINDER AND PISTON
Order
1
2
3
4
5
6
7
Job/Part
Removing the cylinder and piston
Cylinder head
Cylinder
Cylinder gasket
Dowel pin
Piston pin clip
Piston pin
Piston
Piston ring set
Q’ty
1
1
2
2
1
1
1
Remarks
Remove the parts in the order listed.
Refer to “CYLINDER HEAD”.
Refer to “INSTALLING THE CYLINDER”.
Refer to “REMOVING THE PISTON”
and “INSTALLING THE PISTON”.
For installation, reverse the removal procedure.
4 - 23
CYLINDER AND PISTON
ENG
EBS00247
REMOVING THE PISTON
1. Remove:
• piston pin clips 1
• piston pin 2
• piston 3
3
NOTE:
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 4.
_
2
1
Piston pin puller set
P/N. YU-01304, 90890-01304
CAUTION:
_
Do not use a hammer to drive the piston
pin out.
2. Remove:
• piston rings
NOTE:
Spread the end gaps apart while at the same
time lifting the piston ring over the top of the
piston crown.
_
EBS00249
CHECKING THE CYLINDER AND PISTON
1. Check:
• piston wall
• cylinder wall
Vertical scratches → Rebore or replace the
cylinder, and replace the piston and piston
rings as a set.
2. Measure:
• piston-to-cylinder clearance
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Measure cylinder bore “C” with the cylinder
bore gauge.
NOTE:
Measure cylinder bore “C” by taking side-toside and front-to-back measurements of the
cylinder. Then, find the average of the measurements.
_
4 - 24
CYLINDER AND PISTON
ENG
Cylinder bore “C”
39.000 ~ 39.005 mm
(1.5354 ~ 1.5356 in)
Taper limit “T”
0.05 mm (0.002 in)
Out-of-round “R”
0.01 mm (0.0004 in)
“C” = maximum of D1 ~ D2
“T” = maximum of D1 or D2 –
maximum of D5 or D6
“R” = maximum of D1, D3 or D5 –
minimum of D2, D4 or D6
b. If out of specification, rebore or replace the
cylinder, and replace the piston and piston
rings as a set.
c. Measure piston skirt diameter “P” with the
micrometer.
a 5 mm (0.20 in) from the bottom edge of the piston
Piston size “P”
Standard
38.960 ~ 38.975 mm
(1.5339 ~ 1.5344 in)
d. If out of specification, replace the piston and
piston rings as a set.
e. Calculate the piston-to-cylinder clearance
with the following formula.
Piston-to-cylinder clearance =
Cylinder bore “C” –
Piston skirt diameter “P”
Piston-to-cylinder clearance
0.025 ~ 0.045 mm
(0.0010 ~ 0.0018 in)
<Limit>: 0.15 mm (0.0059 in)
f. If out of specification, rebore or replace the
cylinder, and replace the piston and piston
rings as a set.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4 - 25
CYLINDER AND PISTON
ENG
EBS00250
CHECKING THE PISTON RINGS
1. Measure:
• piston ring side clearance
Out of specification → Replace the piston
and piston rings as a set.
NOTE:
Before measuring the piston ring side clearance, eliminate any carbon deposits from the
piston ring grooves and piston rings.
_
Piston ring side clearance
Top ring
0.030 ~ 0.065 mm
(0.0012 ~ 0.0026 in)
<Limit>: 0.12 mm (0.0047 in)
2nd ring
0.020 ~ 0.055 mm
(0.0008 ~ 0.0022 in)
<Limit>: 0.12 mm (0.0047 in)
2. Install:
• piston ring
(into the cylinder)
NOTE:
Level the piston ring into the cylinder with the
piston crown.
_
3. Measure:
• piston ring end gap
Out of specification → Replace the piston
ring.
NOTE:
The oil ring expander spacer’s end gap cannot
be measured. If the oil ring rail’s gap is excessive, replace all three piston rings.
_
Piston ring end gap
Top ring
0.08 ~ 0.20 mm
(0.0031 ~ 0.0079 in)
<Limit>: 0.45 mm (0.0177 in)
2nd ring
0.05 ~ 0.20 mm
(0.0020 ~ 0.0079 in)
<Limit>: 0.55 mm (0.0217 in)
Oil ring
0.20 ~ 0.70 mm
(0.0079 ~ 0.0276 in)
4 - 26
CYLINDER AND PISTON
ENG
EBS00251
CHECKING THE PISTON PIN
1. Check:
• piston pin
Blue discoloration/grooves → Replace the
piston pin and then check the lubrication
system.
2. Measure:
• piston pin outside diameter a
Out of specification → Replace the piston
pin.
Piston pin outside diameter
12.996 ~ 13.000 mm
(0.5117 ~ 0.5118 in)
<Limit>: 12.976 mm (0.5109 in)
3. Measure:
• piston pin bore diameter b
Out of specification → Replace the piston.
Piston pin bore diameter
13.002 ~ 13.013 mm
(0.5119 ~ 0.5123 in)
<Limit>: 13.043 mm (0.5135 in)
4. Calculate:
• piston-pin-to-piston-pin-bore clearance
Out of specification → Replace the piston
pin and piston as a set.
Piston-pin-to-piston-pin-bore clearance =
Piston pin bore diameter b –
Piston pin outside diameter a
Piston-pin-to-piston clearance
0.002 ~ 0.017 mm
(0.00008 ~ 0.00067 in)
<Limit>: 0.067 mm (0.00264 in)
4 - 27
CYLINDER AND PISTON
ENG
EBS00252
INSTALLING THE PISTON
1. Install:
• piston rings
(onto the piston)
NOTE:
• 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.
_
120˚
e
120˚
a
120˚
f f
d
c
b
2.
•
•
•
a Top ring end
b Upper oil ring rail end
c Expander end
d Lower oil ring rail end
e 2nd ring end
f 20 mm (0.79 in)
3.
•
•
•
1
Position:
top ring
2nd ring
oil ring
Offset the piston ring end gaps as shown.
Install:
piston 1
piston pin 2
piston pin clips 3 New
NOTE:
• Apply engine oil onto the piston pin, piston
rings 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 clips, cover
the crankcase with a clean rag to prevent the
piston pin clips from falling into the crankcase.
_
2
3 New
4.
•
•
•
Lubricate:
piston
piston rings
cylinder
NOTE:
Apply a liberal coating of engine oil.
_
4 - 28
CYLINDER AND PISTON
ENG
EBS00253
INSTALLING THE CYLINDER
1. Install:
• cylinder
NOTE:
Install the cylinder with one hand while compressing the piston rings with the other hand.
_
CAUTION:
_
• Be careful not to damage the timing chain
damper during installation.
• Pass the timing chain through the timing
chain cavity.
4 - 29
C.D.I. MAGNETO
ENG
EBS00256
C.D.I. MAGNETO
Order
Job/Part
Removing the C.D.I. magneto
Rear fender
Q’ty
1
Shift lever
1
2
3
4
5
6
C.D.I. magneto cover
C.D.I. magneto cover gasket
Dowel pin
C.D.I. magneto rotor
Woodruff key
1
1
2
1
1
7
8
Pickup coil/stator assembly
Neutral switch
1
1
Remarks
Remove the parts in the order listed.
Refer to “SEAT, FENDERS AND FUEL
TANK” in chapter 3.
Refer to “INSTALLING THE SHIFT
LEVER”.
Refer to “REMOVING THE C.D.I. MAGNETO ROTOR” and “INSTALLING THE
C.D.I. MAGNETO ROTOR”.
For installation, reverse the removal procedure.
4 - 30
C.D.I. MAGNETO
ENG
EBS00259
1
2
REMOVING THE C.D.I. MAGNETO ROTOR
1. Remove:
• C.D.I. magneto rotor nut
• washer
NOTE:
• While holding the C.D.I. magneto rotor 1
with the sheave holder 2, loosen the rotor
nut.
• Do not allow the sheave holder to touch the
projection on the rotor.
_
Sheave holder
P/N. YS-01880-A, 90890-01701
2. Remove:
• C.D.I. magneto rotor 1
• woodruff key
NOTE:
Use the flywheel puller 2.
_
1
2
Flywheel puller
P/N. YM-01189, 90890-01189
EBS00262
CHECKING THE PICKUP COIL/STATOR
ASSEMBLY
1. Check:
• pickup coil/stator assembly
Damage → Replace.
4 - 31
C.D.I. MAGNETO
ENG
EBS00268
INSTALLING THE C.D.I. MAGNETO ROTOR
1. Install:
• woodruff key
• C.D.I. magneto rotor
NOTE:
• Before installing the rotor, clean the outside
of the crankshaft and the inside of the rotor.
• After installing the rotor, check that the rotor
rotates smoothly. If not, reinstall the key and
rotor.
_
2
1
2. Tighten:
• C.D.I. magneto rotor nut
T.
R.
40 Nm (4.0 m · kg, 29 ft · lb)
NOTE:
• While holding the C.D.I. magneto rotor 1
with the sheave holder 2, tighten the C.D.I.
magneto rotor nut.
• Do not allow the sheave holder to touch the
projection on the rotor.
_
Sheave holder
P/N. YS-01880-A, 90890-01701
a
INSTALLING THE SHIFT LEVER
1. Install:
• shift lever
NOTE:
Temporarily install the left footrest board, and
then install the shift lever and align it with the
mark a on the left footrest board.
4 - 32
CLUTCH
ENG
EBS00291
CLUTCH
Order
1
2
3
4
5
6
7
8
Job/Part
Removing the clutch
Engine oil
Q’ty
C.D.I. magneto cover
Clutch cover
1
Clutch cover gasket
Dowel pin
Push plate
Circlip
Pressure plate
Push rod
Friction plate 1 (with black color marking)
1
2
1
1
1
1
4
4 - 33
Remarks
Remove the parts in the order listed.
Drain.
Refer to “CHANGING THE ENGINE OIL”
in chapter 3.
Refer to “C.D.I. MAGNETO”.
Refer to “REMOVING THE CLUTCH” and
“INSTALLING THE CLUTCH”.
Refer to “INSTALLING THE CLUTCH”.
CLUTCH
Order
9
10
11
12
13
14
15
16
17
18
19
Job/Part
Clutch plate 1
Clutch plate 2
Friction plate 2
Thrust weight plate
Clutch ball
Thrust plate
Clutch boss
Clutch boss one-way cam
Primary driven gear/clutch housing
Spacer
Primary drive gear
ENG
Q’ty
Remarks
1
3
1
1
12
Refer to “INSTALLING THE CLUTCH”.
1
1
1
1
1
1
Refer to “REMOVING THE PRIMARY
DRIVE GEAR” and “INSTALLING THE
PRIMARY DRIVE GEAR”.
For installation, reverse the removal procedure.
4 - 34
CLUTCH
ENG
EBS00297
REMOVING THE CLUTCH
1. Remove:
• clutch cover
NOTE:
Loosen each screw 1/4 of a turn at a time, in
stages and in a crisscross pattern. After all of
the screws are fully loosened, remove them.
_
2. Loosen:
• clutch boss nut 1
NOTE:
While holding the clutch boss 2 with the clutch
holder 3, loosen the clutch boss nut.
_
3
Clutch holder
P/N. 90890-04100
2
1
EBS00298
REMOVING THE PRIMARY DRIVE GEAR
1. Loosen:
• primary drive gear nut 1
3
2
NOTE:
Place an aluminum plate 2 between the teeth
of the primary driven gear/clutch housing 3
and primary drive gear 4.
_
1
4
EBS00300
CHECKING THE FRICTION PLATES
The following procedure applies to all of the
friction plates.
1. Check:
• friction plate
Damage/wear → Replace the friction plates
as a set.
2. Measure:
• friction plate thickness
Out of specification → Replace the friction
plates as a set.
NOTE:
Measure the friction plate at four places.
_
Friction plate thickness
2.92 ~ 3.08 mm (0.115 ~ 0.121 in)
<Limit>: 2.90 mm (0.114 in)
4 - 35
CLUTCH
ENG
EBS00301
CHECKING THE CLUTCH PLATES
The following procedure applies to all of the
clutch plates.
1. Check:
• clutch plate
Damage → Replace the clutch plates as a
set.
2. Measure:
• clutch plate warpage
(with a surface plate and thickness gauge
1)
Out of specification → Replace the clutch
plates as a set.
Clutch plate warpage limit
0.06 mm (0.002 in)
EBS00302
CHECKING THE CLUTCH SPRINGS
The following procedure applies to all of the
clutch springs.
1. Check:
• clutch spring
Damage → Replace the clutch springs as a
set.
2. Measure:
• clutch spring free length a
Out of specification → Replace the clutch
springs as a set.
Clutch spring free length
31.9 mm (1.26 in)
<Limit>: 30.3 mm (1.19 in)
EBS00303
CHECKING THE CLUTCH HOUSING
1. Check:
• clutch housing dogs
Damage/pitting/wear → Deburr the clutch
housing dogs or replace the clutch housing.
• clutch housing bearing
Damage/pitting/wear → Replace.
NOTE:
Pitting on the clutch housing dogs will cause
erratic clutch operation.
_
4 - 36
CLUTCH
ENG
EBS00304
CHECKING THE CLUTCH BOSS
1. Check:
• clutch boss splines
• clutch boss cam groove
• clutch boss one-way cam
Damage/pitting/wear → Replace the clutch
boss and clutch boss one-way cam as a
set.
NOTE:
Pitting on the clutch boss splines will cause
erratic clutch operation.
_
EBS00305
CHECKING THE PRESSURE PLATE
1. Check:
• pressure plate
Cracks/damage → Replace.
CHECKING THE CLUTCH BALLS
1. Check:
• clutch ball
Pitting/damage/wear → Replace the clutch
balls as a set.
EBS00307
2
1
CHECKING THE PRIMARY DRIVE GEARS
1. Check:
• primary drive gear 1
• primary driven gear 2
Damage/wear → Replace the primary drive
gear and clutch housing as a set.
Excessive noise during operation →
Replace the primary drive gear and clutch
housing as a set.
4 - 37
CLUTCH
ENG
EBS00310
INSTALLING THE PRIMARY DRIVE GEAR
1. Tighten:
• primary drive gear nut 1
3
T.
R.
50 Nm (5.0 m · kg, 36 ft · lb)
NOTE:
Place an aluminum plate 2 between the teeth
of the primary driven gear/clutch housing 3
and primary drive gear 4.
_
2
1
4
Sheave holder
P/N. YS-01880-A, 90890-01701
1
1
INSTALLING THE CLUTCH
1. Install:
• clutch balls
NOTE:
Install the clutch balls 1 on the primary driven
gear/clutch housing as shown.
1
1
b
a
2.
•
•
•
Install:
thrust weight plate
clutch boss one-way cam
clutch boss
NOTE:
Align section a of the clutch boss one-way
cam with section b of the clutch boss and
then install the primary driven gear/clutch
housing.
4 - 38
CLUTCH
ENG
3.
•
•
•
Install:
friction plate 2 1
clutch plates 2 2
friction plates 1 (with black color marking)
3
• clutch plate 1 4
5
5 thrust weight plate
a silver section
1
NOTE:
Install the clutch plates and friction plates alternately on the clutch boss, starting and ending
with a friction plate.
3
2
3
4
a
CAUTION:
• The friction plate 2 1 must be placed
between the thrust weight plate and the
third clutch plate 2.
• The clutch plate 1 4 must be placed
between the first and second friction
plate 1.
4. Adjust:
• friction plate height
2
1
a
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Push the friction plate 1 1 down by hand.
b. Measure the friction plate height a (distance between the primary driven gear/
clutch housing 2 and friction plate 11).
Friction plate height
1.30 ~ 1.65 mm (0.051 ~ 0.065 in)
c. If the height is out of specification, adjust
the friction plate height.
d. Remove the clutch plate 1, friction plates 1,
clutch plates 2, and friction plate 2.
e. Select the suitable clutch plates 2 (3 plates)
using the following chart.
Clutch plates 2 (3 plates)
Thickness (mm)
1.2
1.6
1.4
f. Install all parts. Refer to step 2.
g. Remeasure the friction plate height.
h. Remove all parts.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4 - 39
CLUTCH
ENG
5. Install:
• clutch housing 1
NOTE:
Make sure that the primary driven gear teeth
and primary drive gear teeth mesh correctly.
_
1
6. Install:
• clutch boss one-way cam 1
• clutch boss 2
b
1
a
2
NOTE:
Align section a of the clutch boss one-way
cam with section b of the clutch boss and
then install the primary driven gear/clutch
housing.
7. Tighten:
• clutch boss nut 1
T.
R.
3
60 Nm (6.0 m · kg, 43 ft · lb)
NOTE:
While holding the clutch boss 2 with the clutch
holder 3, tighten the clutch boss nut.
_
2
1
Clutch holder
P/N. 90890-04100
8. Install:
• clutch balls
NOTE:
Install the clutch balls on the primary driven
gear/clutch housing as shown.
4 - 40
CLUTCH
9.
•
•
•
•
•
•
1
2
ENG
Install:
thrust weight plate 1
friction plate 2 2
clutch plates 2 3
friction plates 1 4
clutch plate 1 5
pressure plate 6
a silver section
3
5
6
NOTE:
Install the clutch plates and friction plates alternately on the clutch boss, starting and ending
with a friction plate.
4
4
a
CAUTION:
• The friction plate 2 2 must be placed
between the thrust weight plate and the
third clutch plate 2.
• The clutch plate 1 5 must be placed
between the first and second friction
plate 1.
10.Install:
• clutch cover
T.
R.
7 Nm (0.7 m · kg, 5.1 ft · lb)
NOTE:
Tighten the screws in stage, using a crisscross
pattern.
_
4 - 41
STARTER CLUTCH AND OIL PUMP
ENG
EBS00315
STARTER CLUTCH AND OIL PUMP
Order
1
2
3
4
5
6
7
8
9
Job/Part
Removing the starter clutch and oil
pump
Clutch assembly
Starter idle gear assembly
Starter wheel gear
Starter clutch assembly
Spacer
Oil pump drive gear
Oil pump driven gear
Oil pump assembly
Oil pump gasket
Oil strainer
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “CLUTCH”.
1
1
1
1
1
1
1
1
1
For installation, reverse the removal procedure.
4 - 42
ENG
STARTER CLUTCH AND OIL PUMP
EBS00316
5
4
3
2
1
E
Order
1
2
3
4
5
Job/Part
Disassembling the oil pump
Oil pump housing cover
Oil pump shaft
Inner rotor
Outer rotor
Oil pump housing
Q’ty
Remarks
Remove the parts in the order listed.
1
1
1
1
1
For assembly, reverse the disassembly
procedure.
4 - 43
STARTER CLUTCH AND OIL PUMP
ENG
EBS00263
CHECKING THE STARTER CLUTCH
1. Check:
• starter clutch rollers 1
Cracks/damage → Replace.
2. Check:
• starter clutch screws 1
Loose → Replace with a new one, and
clinch the end of the screw.
T.
R.
Starter clutch screw
10 Nm (1.0 m · kg, 7.2 ft · lb)
LOCTITE®
NOTE:
Lock the threads on the starter clutch screws
by staking them with a center punch.
3. Check:
• starter clutch operation
É
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
È
a. Install the starter wheel gear to the starter
clutch, and hold the starter clutch.
b. When turning the starter wheel gear clockwise È, the starter clutch and the wheel
gear should be engaged.
If not, the starter clutch is faulty. Replace it.
c. When turning the starter wheel gear counterclockwise É, the starter wheel gear
should turn freely.
If not, the starter clutch is faulty. Replace it.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4 - 44
STARTER CLUTCH AND OIL PUMP
2
1
ENG
4. Check:
• starter idle gear teeth 1
• starter wheel gear teeth 2
Burrs/clips/roughness/wear → Replace.
5. Check:
• starter wheel gear contacting surface a
Damage/pitting/wear → Replace.
a
EBS00330
CHECKING THE OIL PUMP
1. Check:
• oil pump drive gear 1
• oil pump driven gear 2
• oil pump housing 3
• oil pump housing cover 4
Cracks/wear/damage → Replace.
2. Clean:
• oil strainer 1
Damage → Replace.
4 - 45
STARTER CLUTCH AND OIL PUMP
ENG
3. Measure:
• inner-rotor-to-outer-rotor-tip clearance a
• outer-rotor-to-oil-pump-housing clearance
b
• oil-pump-housing-to-inner-rotor-and-outerrotor clearance c
Out of specification → Replace the oil
pump.
1 Inner rotor
2 Outer rotor
3 Oil pump housing
Inner-rotor-to-outer-rotor-tip
clearance
0.05 ~ 0.07 mm
(0.002 ~ 0.003 in)
<Limit>: 0.15 mm (0.006 in)
Outer-rotor-to-oil-pump-housing
clearance
0.013 ~ 0.036 mm
(0.0005 ~ 0.0014 in)
<Limit>: 0.106 mm (0.0042 in)
Oil-pump-housing-to-inner-rotorand-outer-rotor clearance
0.06 ~ 0.10 mm
(0.0024 ~ 0.0039 in)
<Limit>: 0.17 mm (0.0067 in)
4. Check:
• oil pump operation
Rough movement → Repeat steps #1 and
#3 or replace the defective parts.
4 - 46
SHIFT SHAFT
ENG
SHIFT SHAFT
Order
1
2
3
Job/Part
Removing the shift shaft
Clutch assembly
Shift shaft
Stopper lever
Dowel pin
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “CLUTCH”.
1
1
5
For installation, reverse the removal procedure.
4 - 47
SHIFT SHAFT
ENG
EBS01018
CHECKING THE SHIFT SHAFT
1. Check:
• shift shaft 1
Bends/damage/wear → Replace.
• shift shaft spring 2
Damage/wear → Replace.
EBS01019
CHECKING THE STOPPER LEVER
1. Check:
• stopper lever 1
• stopper lever spring 2
Bends/damage → Replace.
Roller turns roughly → Replace the stopper
lever.
INSTALLING THE STOPPER LEVER
1. Install:
• stopper lever 1
1
INSTALLING THE SHIFT SHAFT
1. Install:
• shift shaft 1
3
1
NOTE:
Hook the hooked end of the stopper lever
spring onto the stopper lever and catch the
straight end of the stopper lever spring onto
the crankcase.
2
NOTE:
• Install the end of the shift shaft spring onto
the shift shaft spring stopper 2.
• Make sure that the arm section of the shift
shaft contacts the dowel pins on the shift
drum 3.
4 - 48
CRANKCASE
ENG
EBS00319
CRANKCASE
Order
1
2
3
4
5
Job/Part
Removing the timing chain and separating the crankcase
Engine
Cylinder head
Cylinder and piston
C.D.I. magneto
Clutch
Starter clutch and oil pump
Shift shaft
Timing chain
Shift drum retainer
Right crankcase
Dowel pin
Left crankcase
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “ENGINE”.
Refer to “CYLINDER HEAD”.
Refer to “CYLINDER AND PISTON”.
Refer to “C.D.I. MAGNETO”.
Refer to “CLUTCH”.
Refer to “STARTER CLUTCH AND OIL
PUMP”.
Refer to “SHIFT SHAFT”.
1
1
1
2
1
4 - 49
Refer to “SEPARATING THE CRANKCASE” and “ASSEMBLING THE
CRANKCASE”.
For installation, reverse the removal procedure.
CRANKCASE
ENG
EBS00321
CRANKCASE BEARINGS
T.
R.
8 Nm (0.8 m • kg, 5.8 ft • Ib)
1
2
E
2
2
LT
E
2
2
2
E
E
Order
1
2
Job/Part
Removing the crankcase bearings
Crankshaft
Transmission
Middle driven pinion gear
Bearing retainer
Bearing
Q’ty
1
6
4 - 50
Remarks
Remove the parts in the order listed.
Refer to “CRANKSHAFT”.
Refer to “TRANSMISSION”.
Refer to “MIDDLE GEAR”.
Refer to “INSTALLING THE BEARINGS”.
For installation, reverse the removal procedure.
CRANKCASE
ENG
EBS00333
SEPARATING THE CRANKCASE
1. Separate:
• right crankcase
• left crankcase
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the crankcase screws.
NOTE:
• Loosen each screw 1/4 of a turn at a time
and after all the screws are loosened,
remove them.
• Loosen the screws in stages, using a crisscross pattern.
_
b. Remove the right crankcase.
NOTE:
Insert a screwdriver or pry bar into the pry
points in the crankcase and then carefully pry
apart the crankcase halves.
_
CAUTION:
_
Use a soft hammer to tap on one side of the
crankcase. Tap only on reinforced portions
of the crankcase. Do not tap on the crankcase mating surfaces. Work slowly and
carefully. Make sure that the crankcase
halves separate evenly.
c. Remove the dowel pins.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EBS00335
CHECKING THE TIMING CHAIN
1. Check:
• timing chain
Cracks/stiff → Replace the timing chain and
camshaft sprocket as a set.
4 - 51
CRANKCASE
ENG
EBS00339
CHECKING THE BEARINGS AND OIL
SEALS
1. Check:
• bearings
Clean and lubricate, then rotate the inner
race with a finger.
Roughness → Replace.
2. Check:
• oil seals
Damage/wear → Replace.
EBS00338
CHECKING THE CRANKCASE
1. Thoroughly wash the case halves in a mild
solvent.
2. Clean all the gasket mating surfaces and
crankcase mating surfaces thoroughly.
3. Check:
• crankcase
Cracks/damage → Replace.
• oil delivery passages
Clogged → Blow out with compressed air.
b
2
1
a
INSTALLING THE BEARINGS
1. Install:
• left main axle bearing 1
NOTE:
Press the left main axle bearing into the left
crankcase 2, as shown in the illustration.
a 34.0 ~ 34.5 mm (1.34 ~ 1.36 in)
b Crankcase mating surface
4 - 52
CRANKCASE
ENG
EBS00341
ASSEMBLING THE CRANKCASE
1. Apply:
• sealant (Quick Gasket®) or Yamaha bond
No. 1215 1
(to the mating surfaces of both case halves)
Sealant (Quick Gasket®)
P/N. ACC-11001-05-01
Yamaha bond No. 1215
P/N. 90890-85505
2. Install:
• dowel pin
3. Fit the right crankcase onto the left case.
Tap lightly on the case with a soft hammer.
CAUTION:
_
2
4
Before installing and torquing the crankcase holding screws, be sure to check
whether the transmission is functioning
properly by manually rotating the shift
drum in both directions.
3
4.
•
•
5.
•
3
New 1
2
R.
2
T.
2
Install:
gaskets 1 New
crankcase screws
Tighten:
crankcase screws
2 Screw:
3 Screw:
4 Screw:
7 Nm (0.7 m · kg, 5.1 ft · lb)
= 45 mm
= 60 mm
= 75 mm
NOTE:
Tighten the screws in stages, using a crisscross pattern.
_
6. Apply:
• 4-stroke engine oil
(to the crankshaft pin, bearing and oil delivery hole)
7. Check:
• crankshaft and transmission operation
Unsmooth operation → Repair.
4 - 53
CRANKSHAFT
ENG
EBS00326
CRANKSHAFT
Order
1
Job/Part
Removing the crankshaft
Crankcase
Crankshaft
Q’ty
1
4 - 54
Remarks
Remove the parts in the order listed.
Separate.
Refer to “CRANKCASE”.
Refer to “INSTALLING THE CRANKSHAFT”.
For installation, reverse the removal procedure.
CRANKSHAFT
ENG
EBS00361
f
C2
C1
CHECKING THE CRANKSHAFT
1. Measure:
• crank width a
Out of specification → Replace the crankshaft.
Crank width
40.20 ~ 40.25 mm
(1.5827 ~ 1.5846 in)
d
a
2. Measure:
• side clearance d
Out of specification → Replace the crankshaft.
Big end side clearance
0.10 ~ 0.40 mm
(0.0039 ~ 0.0157 in)
<Limit>: 0.50 mm (0.0197 in)
3. Measure:
• runout c
Out of specification → Replace the crankshaft.
Runout limit
C1: 0.05 mm (0.0020 in)
C2: 0.04 mm (0.0016 in)
4. Measure:
• small end free play f
Out of specification → Replace the big end
bearing, crankshaft pin, connecting rod and/
or side washer as a set.
Small end free play
Standard
0.80 ~ 1.00 mm
(0.0315 ~ 0.0394 in)
<Limit>: 1.50 mm (0.0591 in)
EBS00362
INSTALLING THE CRANKSHAFT
1. Install:
• crankshaft
CAUTION:
_
Apply engine oil to each bearing to protect
the crankshaft against scratches and to
make installation easier.
4 - 55
TRANSMISSION
ENG
EBS00345
TRANSMISSION
Order
1
2
3
4
5
6
7
8
Job/Part
Removing the transmission
Crankcase
Main axle/1st pinion gear
Shift fork guide bar
Shift fork
Drive axle/middle drive pinion gear
assembly
Shift drum
1st wheel gear
Drive axle dog gear
Middle drive gear shim
Q’ty
1
1
1
1
Remarks
Remove the parts in the order listed.
Separate.
Refer to “CRANKCASE”.
Refer to “REMOVING THE TRANSMISSION” and “INSTALLING THE TRANSMISSION”.
1
1
1
1
For installation, reverse the removal procedure.
4 - 56
TRANSMISSION
4
1
2
3
ENG
REMOVING THE TRANSMISSION
1. Remove:
• shift fork guide bar 1
• shift fork 2
• drive axle/middle drive pinion gear assembly 3
• shift drum 4
NOTE:
Remove the shift fork guide bar, shift fork,
drive axle/middle drive gear assembly, and
shift drum from the crankcase together.
EBS00350
CHECKING THE SHIFT FORK
1. Check:
• shift fork cam follower 1
• shift fork pawl 2
Bends/damage/scoring/wear
the shift fork.
→
Replace
2. Check:
• shift fork guide bar
Roll the shift fork guide bar on a flat surface.
Bends → Replace.
WARNING
_
Do not attempt to straighten a bent shift
fork guide bar.
3. Check:
• shift fork movement
(along the shift fork guide bar)
Rough movement → Replace the shift fork
and shift fork guide bar as a set.
4 - 57
TRANSMISSION
ENG
EBS01103
CHECKING THE SHIFT DRUM
1. Check:
• shift drum grooves
Damage/scratches/wear → Replace the
shift drum assembly.
• shift drum segment 1
Damage/wear → Replace the shift drum
assembly.
EBS00354
CHECKING THE TRANSMISSION
1. Measure:
• main axle runout
(with a centering device and dial gauge 1)
Out of specification → Replace the main
axle.
Main axle runout limit
0.08 mm (0.0031 in)
1
2. Measure:
• drive axle runout
(with a centering device and dial gauge 1)
Out of specification → Replace the drive
axle.
Drive axle runout limit
0.08 mm (0.0031 in)
3. Check:
• transmission gears
Blue discoloration/pitting/wear → Replace
the defective gear(s).
• transmission gear dogs
Cracks/damage/rounded edges → Replace
the defective gear(s).
4. Check:
• transmission gear engagement
(each pinion gear to its respective wheel
gear)
Incorrect → Reassemble the transmission
axle assemblies.
5. Check:
• transmission gear movement
Rough movement → Replace the defective
part(s).
6. Check:
• circlips
Bends/damage/looseness → Replace.
4 - 58
TRANSMISSION
ENG
EBS00357
2
1
4
3
a
INSTALLING THE TRANSMISSION
1. Install:
• shift drum 1
• drive axle/middle drive pinion gear assembly 2
• shift fork 3
• shift fork guide bar 4
NOTE:
• The embossed marks on the shift fork should
face towards the left of the engine.
• Be sure to install the forked section a of the
drive axle/middle drive gear assembly
around the shift fork guide bar when installing the transmission.
_
2. Check:
• transmission
Rough movement → Repair.
NOTE:
• Oil each gear and bearing thoroughly.
• Before assembling the crankcase, be sure
that the transmission is in neutral and that
the gears turn freely.
_
4 - 59
MIDDLE GEAR
ENG
EBS00363
MIDDLE GEAR
Order
1
2
3
4
5
6
7
8
Job/Part
Removing the middle gear
Crankcase
Drive axle/middle drive pinion gear
assembly
Middle drive gear shim
Middle driven gear shim
Bearing
Universal joint
Universal joint yoke
Middle driven shaft
(with driven pinion gear)
Bearing retainer
Bearing housing
Q’ty
Remarks
Remove the parts in the order listed.
Separate.
Refer to “CRANKCASE”.
Refer to “TRANSMISSION”.
1
Refer to “SELECTING MIDDLE DRIVEN
GEAR SHIMS”.
4
1
2
1
Refer to “REMOVING THE MIDDLE
DRIVEN SHAFT” and “INSTALLING
THE MIDDLE DRIVEN SHAFT”.
1
1
For installation, reverse the removal procedure.
4 - 60
MIDDLE GEAR
ENG
EBS00366
REMOVING THE MIDDLE DRIVEN SHAFT
1. Remove:
• universal joint
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the circlips.
b. Place the universal joint in a press.
c. With a suitable diameter pipe 1 beneath
the yoke 2, press the bearings 3 into the
pipe as shown.
NOTE:
It may be necessary to lightly tap the yoke with
a punch.
_
d. Repeat the steps for the opposite bearing.
e. Remove the yoke.
NOTE:
It may be necessary to lightly tap the yoke with
a punch.
_
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3
2
1
2.
•
•
•
Remove:
nut 1
washer
universal joint yoke (front side)
NOTE:
Use the universal joint holder 2 and attachment 3 to hold the universal joint yoke.
_
3
Universal joint holder
P/N. YM-04062, 90890-04062
Universal joint holder attachment
P/N. 90890-04096
4 - 61
MIDDLE GEAR
ENG
3. Remove:
• bearing housing assembly 1
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Clean the outside of the middle driven shaft.
b. Place the middle driven shaft onto a hydraulic press.
CAUTION:
_
• Never directly press the shaft end with a
hydraulic press, this will result in damage
to the shaft thread.
• Install the suitable socket 2 on the shaft
end to protect the thread from damage.
c. Press the shaft end and remove the bearing
housing.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4. Remove:
• bearing retainer
• bearing
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
1
2
a. Place a folded rag 1.
b. Secure the bearing housing edge in the
vise.
c. Attach the damper rod holder 2.
27-mm hexagon wrench
P/N. YM-01363
Damper rod holder (27 mm)
P/N. 90890-01388
d. Remove the bearing retainer and bearing.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EBS01021
CHECKING THE PINION GEARS
1. Check:
• drive pinion gear teeth 1
• driven pinion gear teeth 2
Pitting/galling/wear → Replace.
4 - 62
MIDDLE GEAR
ENG
2. Check:
• O-ring
Damage → Replace.
• bearings
Pitting/damage → Replace.
3. Check:
• universal joint movement
Roughness → Replace universal joint.
EBS00370
SELECTING MIDDLE DRIVEN GEAR SHIMS
When the drive and driven gear, bearing housing assembly and/or crankcase replaced, be
sure to adjust the gear shim 1.
1. Select:
• middle driven gear shim 1
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Measure the distance a between the middle driven shaft bearing housing and the
middle driven pinion gear.
b. Determine the difference using the following
chart.
a
a (mm)
Difference (mm)
37.83 ≤ a ≤ 37.90
0.4
37.90 < a ≤ 38.00
0.5
38.00 < a ≤ 38.10
0.6
38.10 < a ≤ 38.20
0.7
38.20 < a ≤ 38.30
0.8
38.30 < a ≤ 38.40
0.9
38.40 ≤ a ≤ 38.45
1.0
c. Select the suitable shim(s) according to the
following chart.
Difference
Suitable shim(s)
Thickness (mm)
Q’ty (pcs.)
0.4
0.4
1
0.5
0.5
1
0.6
0.3
2
0.7
0.3 + 0.4
1+1
0.8
0.4
2
0.9
0.4 + 0.5
1+1
1.0
0.5
2
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4 - 63
MIDDLE GEAR
ENG
EBS00373
INSTALLING THE MIDDLE DRIVEN SHAFT
1. Install:
• bearing retainer New
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Secure the bearing housing edge in the vise
with a clean rag 1.
1
NOTE:
Apply locking agent (LOCTITE®) to the threads
of bearing retainer.
2
b. Attach the damper rod holder 2.
27-mm hexagon wrench
P/N. YM-01363
Damper rod holder (27 mm)
P/N. 90890-01388
c. Tighten the bearing retainer.
T.
R.
Bearing retainer
60 Nm (6.0 m · kg, 43 ft · lb)
LOCTITE®
NOTE:
Lock the threads with a drift punch.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3
2
Install:
universal joint yoke (front side)
washer
90 Nm (9.0 m · kg, 65 ft · lb)
nut 1
T.
R.
1
2.
•
•
•
NOTE:
• Use the universal joint holder 2 and attachment 3 to hold the yoke.
• Apply locking agent (LOCTITE®) to the nut
threads.
• Lock the threads with a drift punch.
_
3
Universal joint holder
P/N. YM-04062, 90890-04062
Universal joint holder attachment
P/N. 90890-04096
1
4 - 64
MIDDLE GEAR
ENG
3. Install:
• universal joint
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Install the yoke into the universal joint.
b. Apply wheel bearing grease to the bearings.
c. Install the bearing 1 onto the yoke.
CAUTION:
_
Check each bearing. The needles can easily fall out of their races. Slide the yoke
back and forth on the bearings; the yoke
will not go all the way onto a bearing if a
needle is out of place.
d. Press each bearing into the universal joint
using a suitable socket.
NOTE:
The bearing must be inserted far enough into
the universal joint so that the circlip can be
installed.
_
e. Install the circlips into the groove of each
yoke.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4 - 65
MIDDLE GEAR
ENG
EBS00376
MEASURING THE MIDDLE GEAR
BACKLASH
1. Measure:
• middle gear lash
Middle gear lash
0.17 ~ 0.31 mm (0.007 ~ 0.012 in)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Temporarily install the drive axle/middle
drive pinion gear assembly and middle
driven pinion gear.
b. Attach the pinion gear fix clamp 1 to the
drive axle/middle drive pinion gear assembly.
Pinion gear fix clamp
P/N. YM-04129, 90890-04129
NOTE:
Tighten the bolt on one corner of the pinion
gear fix clamp as shown to secure the pinion
gear fix clamp.
c. Attach the gear lash measurement tool 2
and dial gauge 3.
Gear lash measurement tool
P/N. YM-01467, 90890-01467
a 25.2 mm (0.99 in)
d. Measure the gear lash while rotating the
middle driven shaft back and forth.
NOTE:
Measure the gear lash at 4 positions. Rotate
the middle driven gear 90° each time.
_
e. If the gear lash is incorrect, adjust the gear
lash by middle driven gear shim(s).
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4 - 66
CARBURETOR
CARB
EBS00141
CARBURETOR
CARBURETOR
T.
R.
7 Nm (0.7 m • kg, 5.1 ft • Ib)
6
(3)
5
7
9
8
3
4
5
2
Order
1
2
3
4
5
6
7
8
9
Job/Part
Removing the carburetor
Fuel overflow hose
Carburetor air vent hose
Fuel hose
Carburetor assembly
Carburetor top cover
Throttle cable
Spring
Piston valve
Jet needle set
Q’ty
1
1
1
1
1
1
1
1
1
1
Remarks
Remove the parts in the order listed.
Refer to “INSTALLING THE CARBURETOR”.
For installation, reverse the removal procedure.
5-1
CARBURETOR
CARB
EBS00144
Order
Job/Part
Disassembling the carburetor
Q’ty
Remarks
Remove the parts in the order listed.
NOTE:
Before disassembling the carburetor,
make sure to note the number of times
the pilot screw is turned out from the
seated position to its set position.
_
1
2
3
4
5
6
Throttle stop screw
Float chamber
Pilot jet
Main jet
Needle jet
Float pin
1
1
1
1
1
1
5-2
CARBURETOR
Order
7
8
Job/Part
Float
Needle valve
CARB
Q’ty
Remarks
1
Refer to “ASSEMBLING THE CARBURETOR”.
1
For assembly, reverse the disassembly
procedure.
5-3
CARBURETOR
CARB
EBS00146
DISASSEMBLING THE CARBURETOR
NOTE:
Before disassembling the carburetor, make
sure to note the number of times the pilot
screw is turned out from the seated position to
its set position.
_
EBS00148
CHECKING THE CARBURETOR
1. Check:
• carburetor body
• float chamber
Cracks/damage → Replace.
• fuel passage
Contamination → Clean as indicated.
• fuel chamber body
Contamination → Clean.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Wash the carburetor in a petroleum based
solvent. Do not use any caustic carburetor
cleaning solution.
b. Blow out all of the passages and jets with
compressed air.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Check:
• float 1
• float tang 2
Damage → Replace.
3. Check:
• needle valve 1
Contamination/wear/damage → Replace.
5-4
CARBURETOR
CARB
4. Check:
• piston valve 1
Scratches/wear/damage → Replace.
5. Check:
• carburetor top cover 1
• spring 2
Cracks/damage → Replace.
6.
•
•
•
•
•
7.
•
8.
•
5-5
Check:
jet needle 1
main jet 2
needle jet 3
pilot jet 4
throttle stop screw 5
Bends/wear/damage → Replace.
Blockage → Blow out the jets with compressed air.
Check:
piston valve movement
Sticks → Replace the piston valve.
Insert the piston valve into the carburetor
body, and check for free movement.
Check:
choke valve movement
Sticks → Replace.
CARBURETOR
CARB
EBS00150
ASSEMBLING THE CARBURETOR
NOTE:
Before assembling the carburetor, make sure
to turn out the pilot air screw the same number
of times, as noted before disassembly, from
the seated position to the set position.
_
CAUTION:
_
• Before reassembling, wash all of the
parts in a clean petroleum based solvent.
• Always use a new gasket.
INSTALLING THE CARBURETOR
1. Install:
• jet needle set
• piston valve
• spring
• throttle cable
NOTE:
Align the slit 1 of the throttle valve with the tab
2 of the carburetor body.
5-6
CARBURETOR
CARB
EBS00154
MEASURING AND ADJUSTING THE FUEL
LEVEL
1. Measure:
• fuel level a
Out of specification → Adjust.
Fuel level
(below the float chamber mating
surface)
4.0 ~ 5.0 mm (0.16 ~ 0.20 in)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Stand the machine on a level surface.
b. Install the fuel level gauge 1 onto the fuel
drain pipe 2.
Fuel level gauge
P/N. YM-01312-A, 90890-01312
c. Loosen the fuel drain screw 3.
d. Hold the fuel level gauge vertically next to
the line on the float chamber.
e. Measure the fuel level.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Adjust:
• fuel level
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the carburetor assembly.
b. Check the needle valve seat and needle
valve.
c. If either is worn, replace them as a set.
d. If both are fine, adjust the float level by
slightly bending the float tang 1.
e. Install the carburetor assembly.
f. Measure the fuel level again.
g. Repeat steps (a) to (f) until the fuel level is
within specification.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
5-7
TROUBLESHOOTING
DRIV
EBS00155
DRIVE TRAIN
TROUBLESHOOTING
The following conditions may indicate damaged shaft drive components:
Symptoms
Possible Causes
1. A pronounced hesitation or “jerky” movement during acceleration deceleration or
sustained speed. (This must not be confused with engine surging or transmission
characteristics.)
2. A “rolling rumble” noticeable at low speed; a
high-pitched whine; a “clunk” from a shaft
drive component or area.
3. A locked-up condition of the shaft drive train
mechanism, no power transmitted from the
engine to the rear wheels.
A. Bearing damage.
B. Improper gear lash.
C. Gear tooth damage.
D. Broken drive shaft.
E. Broken gear teeth.
F. Seizure due to lack of lubrication.
G. Small foreign objects lodged between the
moving parts.
NOTE:
Areas A, B, and C above may be extremely difficult to diagnose. The symptoms are quite subtle and
difficult to distinguish from normal machine operating noise. If there is reason to believe these components are damaged, remove the components and check them.
_
6-1
TROUBLESHOOTING
DRIV
EBS00156
CHECKING NOISES
1. Investigate any unusual noises.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. A “rolling rumble” noise during coasting,
acceleration, or deceleration. The noise
increases with rear wheel speed, but it does
not increase with higher engine or transmission speeds.
Diagnosis: Possible wheel bearing damage.
b. A “whining” noise that varies with acceleration and deceleration.
Diagnosis: Possible incorrect reassembly,
too-little gear lash.
CAUTION:
_
Too little gear lash is extremely destructive
to the gear teeth. If a test ride following
reassembly indicates this condition, stop
riding immediately to minimize gear damage.
c. A slight “thunk” evident at low speed operation. This noise must be distinguished from
normal machine operation.
Diagnosis: Possible broken gear teeth.
WARNING
_
Stop riding immediately if broken gear
teeth are suspected. This condition could
result in the shaft drive assembly locking
up, causing loss of control of the machine
and possible injury to the rider.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Check:
• drained oil
Drained oil shows large amounts of metal
particles → Check the bearing for seizure.
NOTE:
A small amount of metal particles in the oil is
normal.
_
6-2
6
TROUBLESHOOTING
DRIV
3. Check:
• oil leakage
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Clean the entire machine thoroughly, then
dry it.
b. Apply a leak-localizing compound or dry
powder spray to the shaft drive.
c. Road test the machine for the distance necessary to locate the leak.
Leakage → Check the component housing,
gasket, and/or seal for damage.
Damage → Replace the component.
NOTE:
• An apparent oil leak on a new or nearly new
machine may be the result of a rust preventative coating or excessive seal lubrication.
• Always clean the machine and recheck the
suspected location of an apparent leakage.
_
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
6-3
TROUBLESHOOTING
DRIV
EBS00157
TROUBLESHOOTING CHART
When basic condition “a” and “b” exist, check the following points:
Check the wheel and hub nuts for tightness.
NO
Torque to specification.
(Refer to “FRONT AND REAR WHEELS” in
chapter 7.)
NO
Adjust per instructions.
(Refer to “ADJUSTING THE REAR BRAKE”
in chapter 3.)
NO
Rear axle bearings and rear drive shaft
bearings are probably not damaged. Repeat
the test or remove the individual components.
YES
Check the rear brake adjustment.
YES
Check the rear axle. Feel for bearing damage.
YES
Remove the rear axle. Check for axle bear- YES Replace the rear axle bearing.
ing damage.
(Refer to “REAR AXLE/FINAL DRIVE
ASSEMBLY AND DRIVE SHAFT”.)
NO
Remove the drive shaft components.
6-4
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
EBS00178
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE SHAFT
Order
Job/Part
Removing the rear axle/final drive
assembly and drive shaft
Rear wheels
Q’ty
Brake drum cover
Final gear oil
1
2
3
4
5
Nut
Nut
Final gear case breather hose
Bolt/nut
Swingarm guard
1
1
1
1/1
1
6-5
Remarks
Remove the parts in the order listed.
Refer to “FRONT AND REAR WHEELS”
in chapter 7.
Refer to “FRONT AND REAR BRAKES”
in chapter 7.
Drain.
Refer to “CHANGING THE FINAL GEAR
OIL” in chapter 3.
Refer to “REMOVING THE NUTS” and
“INSTALLING THE NUTS”.
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
Order
6
7
8
Job/Part
Rear axle/final drive assembly
Drive shaft
Coupling gear
Q’ty
1
1
1
6-6
DRIV
Remarks
Refer to “REMOVING THE REAR AXLE/
FINAL DRIVE ASSEMBLY” and
“INSTALLING THE REAR AXLE/FINAL
DRIVE ASSEMBLY”.
For installation, reverse the removal procedure.
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
EBS00179
REAR AXLE/FINAL DRIVE ASSEMBLY
Order
Q’ty
1
2
Job/Part
Disassembling the rear axle/final
drive assembly
Rear axle housing
Rear axle housing bearing retainer
3
4
5
6
7
8
Spacer
Final gear case bearing retainer
Spacer
Final drive pinion gear
Rear axle (with final drive ring gear)
Final gear case
1
1
1
1
1
1
1
1
Remarks
Remove the parts in the order listed.
Refer to “DISASSEMBLING THE REAR
AXLE HOUSING” and “ASSEMBLING
THE REAR AXLE HOUSING”.
Refer to “DISASSEMBLING THE FINAL
GEAR CASE” and “ASSEMBLING THE
FINAL GEAR CASE”.
For assembly, reverse the disassembly
procedure.
6-7
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
REMOVING THE NUTS
1. Place the machine on a level surface.
2. Loosen:
• nuts 1
NOTE:
• Apply the rear brake lever so that the rear
axle does not turn, when loosening the nuts.
• Use an axle nut wrench (36 mm).
_
Axle nut wrench (36 mm)
P/N. YM-37132, 90890-01422
3. Elevate the rear wheels by placing the suitable stand under the frame.
4. Remove:
• rear wheels
• wheel hubs
• nuts
5. Remove:
• rear brake assembly
Refer to “FRONT AND REAR BRAKES” in
chapter 7.
REMOVING THE REAR AXLE/FINAL DRIVE
ASSEMBLY
1. Remove:
• rear axle/final drive assembly 1
NOTE:
Remove the rear axle/final drive assembly as
an assembly after removing each bolt and nut.
6-8
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
EBS00181
DISASSEMBLING THE REAR AXLE
HOUSING
1. Remove:
• rear axle housing bearing retainer
NOTE:
Use a ring nut wrench 1.
_
Ring nut wrench
P/N. YM-38404, 90890-01430
EBS00181
DISASSEMBLING THE FINAL GEAR CASE
1. Remove:
• rear axle
(with final drive ring gear)
CAUTION:
_
Never directly tap the axle end with a hammer, since this will result in damage to the
axle thread and spline.
2. Remove:
• final gear case bearing retainer
NOTE:
Use a ring nut wrench 1.
_
Ring nut wrench
P/N. YM-38404, 90890-01430
3. Remove:
• final drive pinion gear assembly
With a soft hammer, lightly tap on the final
drive pinion gear end.
6-9
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
EBS00190
CHECKING THE REAR AXLE
1. Check:
• rear axle runout a
Out of specification → Replace.
WARNING
_
Do not attempt to straighten a bent axle.
Rear axle runout limit
1.5 mm (0.06 in)
EBS00191
CHECKING THE DRIVE SHAFT
1. Check:
• drive shaft splines 1
• coupling gear splines 2
Wear/damage → Replace.
EBS00192
CHECKING THE REAR AXLE HOUSING
AND FINAL DRIVE ASSEMBLY
1. Check:
• final gear case 1
• rear axle housing 2
Cracks/damage → Replace.
2. Check:
• gear teeth
Pitting/galling/wear → Replace the drive
pinion gear and ring gear as a set.
• oil seals
• O-rings
Damage → Replace.
3. Check:
• bearings
Damage → Replace.
6 - 10
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
EBS00195
ASSEMBLING THE FINAL GEAR CASE
1. Install:
• final drive pinion gear assembly
• spacer 1
• bearing
• final gear case bearing retainer
T.
R.
80 Nm (8.0 m · kg, 58 ft · lb)
Use a ring nut wrench 2.
CAUTION:
_
Always use a new bearing.
Ring nut wrench
P/N. YM-38404, 90890-01430
2. Install:
• oil seal 1
• dust seal 2
NOTE:
Install the oil seal and dust seal as shown.
a 6 ~ 6.5 mm (0.24 ~ 0.26 in)
b 1 ~ 2 mm (0.04 ~ 0.08 in)
EBS00195
ASSEMBLING THE REAR AXLE HOUSING
1. Install:
• rear axle housing bearing retainer
T.
R.
110 Nm (11.0 m · kg, 80 ft · lb)
Use a bearing retainer wrench 1.
CAUTION:
_
Always use a new bearing.
Ring nut wrench
P/N. YM-38404, 90890-01430
2. Install:
• bearing 1
NOTE:
Install the bearing as shown.
a 0.5 mm (0.02 in)
2 rear axle housing bearing retainer
6 - 11
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
EBS00196
INSTALLING THE REAR AXLE/FINAL
DRIVE ASSEMBLY
1. Lubricate:
• drive shaft
• coupling gear
• O-ring
• oil seal
• bearing
Lithium-soap-based grease
2. Install:
• drive shaft
• coupling gear
(to the universal joint)
3. Install:
• rear axle/final drive assembly
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Apply sealant (Quick Gasket®) or Yamaha
bond No. 1215 to the mating surfaces of the
swingarm and the final gear case.
Sealant (Quick Gasket®)
P/N. ACC-11001-05-01
Yamaha bond No. 1215
P/N. 90890-85505
b. Temporarily install the rear axle/final drive
assembly 1 on the swingarm 2. The bolts
and nuts should be temporarily tightened.
c. Check that the rear axle rotates smoothly.
d. Tighten the bolts and nuts.
1 Rear axle/final drive assembly
2 Swingarm
3 Bolt (× 4)
4 Nut (× 3)
5 Bolt (× 6)
T.
R.
Bolt 3
20 Nm (2.0 m · kg, 14 ft · lb)
Nut 4
40 Nm (4.0 m · kg, 29 ft · lb)
Bolt 5
20 Nm (2.0 m · kg, 14 ft · lb)
LOCTITE®
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
6 - 12
REAR AXLE/FINAL DRIVE ASSEMBLY AND DRIVE
SHAFT
DRIV
EBS00397
INSTALLING THE NUTS
1. Tighten:
• nuts 1, 2
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Check if the rear brake assembly is installed
on the rear axle housing. If the rear brake
assembly is not installed, refer to “FRONT
AND REAR BRAKES” in chapter 7 for
installation instructions.
NOTE:
Before tightening the nuts, apply the LOCTITE® to the thread portion of the rear axle.
b. Finger tighten the inside nut 1 while checking the ring gear engagement.
c. Tighten the inside nut with rear axle nut
wrench to specification while holding the
rear axle.
Axle nut wrench (36 mm)
P/N. YM-37132, 90890-01422
T.
Inside nut (first tightening)
110 Nm (11.0 m · kg, 80 ft · lb)
R.
d. Hold the inside nut 1 and tighten the outside nut 2 with the rear axle nut wrench to
specification.
T.
Outside nut
130 Nm (13.0 m · kg, 94 ft · lb)
R.
e. Draw a line a on the inside and outside nut.
f. Hold the outside nut 2 and tighten back the
inside nut 1 with the rear axle nut wrench
to specification.
T.
Inside nut (final tightening)
160 Nm (16.0 m · kg, 115 ft · lb)
R.
g. Measure the distance b between the lines.
If distance b is less then 3 mm (0.12 in),
retighten back the inside nut.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
6 - 13
FRONT AND REAR WHEELS
CHAS
EBS00378
CHASSIS
FRONT AND REAR WHEELS
FRONT WHEELS
Order
Job/Part
Removing the front wheels
Q’ty
Remarks
Remove the parts in the order listed.
Place the machine on a level surface.
WARNING
_
Securely support the machine so there
is no danger of it falling over.
1
2
3
4
Cotter pin
Axle nut
Front wheel
Front brake drum
1
1
1
1
The following procedure applies to both
of the front wheels.
Refer to “INSTALLING THE WHEEL
HUBS”.
Refer to “INSTALLING THE WHEELS”.
For installation, reverse the removal procedure.
7-1
7
FRONT AND REAR WHEELS
CHAS
EBS00379
REAR WHEELS
Order
Job/Part
Removing the rear wheels
Q’ty
Remarks
Remove the parts in the order listed.
Place the machine on a level surface.
WARNING
_
Securely support the machine so there
is no danger of it falling over.
1
2
3
4
Cotter pin
Axle nut
Rear wheel
Rear wheel hub
1
1
1
1
The following procedure applies to both
of the rear wheels.
Refer to “INSTALLING THE WHEEL
HUBS”.
Refer to “INSTALLING THE WHEELS”.
For installation, reverse the removal procedure.
7-2
FRONT AND REAR WHEELS
CHAS
EBS00383
CHECKING THE WHEELS
The following procedure applies to both of the
front and rear wheels.
1. Check:
• wheel
2. Measure:
• wheel runout
Over the specified limit → Replace the
wheel or check the wheel bearing play 1.
Wheel runout limit
Radial 2: 2.0 mm (0.08 in)
Lateral 3: 2.0 mm (0.08 in)
3. Check:
• wheel balance
Out of balance → Adjust.
WARNING
_
After replacing the tire, ride conservatively
to allow the tire to be properly seated in the
rim. Failure to do so may cause an accident
resulting in machine damage and possible
operator injury.
EBS00385
CHECKING THE FRONT WHEEL HUBS
The following procedure applies to both of the
front wheel hubs.
1. Check:
• front wheel hub 1
Cracks/damage → Replace.
2. Check:
• wheel bearings
Wheel hub play/wheel turns roughly →
Replace.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Clean wheel hub exterior.
b. Drive bearing out by pushing spacer aside
and tapping around perimeter of bearing
inner race. Use soft metal drift punch and
hammer. The spacer 1 “floats” between
bearings. Remove both bearings as
described.
7-3
FRONT AND REAR WHEELS
CHAS
WARNING
_
Eye protection is recommended when
using striking tools.
c. To install the wheel bearings, reverse the
above sequence. Use a socket that
matches outside diameter of bearing outer
race to drive in bearing.
CAUTION:
_
Do not strike the center race or balls of the
bearing. Contact should be made only with
the outer race.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EBS00384
CHECKING THE REAR WHEEL HUBS
The following procedure applies to both of the
rear wheel hubs.
1. Check:
• rear wheel hub 1
Cracks/damage → Replace.
• wheel hub splines 2
Wear/damage → Replace.
EBS00390
T.
INSTALLING THE WHEEL HUBS
The following procedure applies to both of the
front and rear wheel hubs.
1. Install:
70 Nm (7.0 m · kg, 50 ft · lb)
• axle nut 1
• cotter pin 2 New
R.
NOTE:
Do not loosen the axle nut after torquing it. If
the axle nut groove is not aligned with the cotter pin hole, align the groove with the hole by
tightening the axle nut.
_
7-4
FRONT AND REAR WHEELS
CHAS
EBS00391
È
INSTALLING THE WHEELS
The following procedure applies to both of the
front and rear wheels.
1. Install:
• wheel
NOTE:
The arrow mark 1 on the tire must point in the
direction of rotation + of the wheel.
_
È Front wheel
É Rear wheel
É
R.
7-5
T.
2. Tighten:
• nuts
28 Nm (2.8 m · kg, 20 ft · lb)
FRONT AND REAR BRAKES
CHAS
EBS00437
FRONT AND REAR BRAKES
FRONT BRAKE
Order
1
2
3
4
5
6
7
8
9
Job/Part
Removing the front brakes
Front wheels
Brake shoe
Front brake cable (drum side)
Brake shoe plate
Brake camshaft lever
Brake shoe wear indicator
Brake camshaft
Left front brake cable (lever side)
Right front brake cable (lever side)
Front brake lever
Q’ty
2
1
1
1
1
1
1
1
1
Remarks
Remove the parts in the order listed.
Refer to “FRONT AND REAR WHEELS”.
The following procedure applies to both
of the front brakes.
Refer to “INSTALLING THE FRONT
BRAKES”.
Refer to “REMOVING THE BRAKES”
and “INSTALLING THE FRONT
BRAKES”.
For installation, reverse the removal procedure.
7-6
FRONT AND REAR BRAKES
CHAS
REAR BRAKE
Order
Job/Part
Removing the rear brake
Q’ty
1
2
3
Brake drum cover
Nut
Nut
1
1
1
4
5
6
7
8
9
10
11
Lock washer
Brake drum
Brake drum boss
Brake shoe
Rear brake cable (drum side)
Brake camshaft lever
Brake shoe wear indicator
Brake camshaft
2
1
1
2
1
1
1
1
7-7
Remarks
Remove the parts in the order listed.
Refer to “FRONT AND REAR WHEELS”.
Refer to “REAR AXLE/FINAL DRIVE
ASSEMBLY AND DRIVE SHAFT” in
chapter 6.
Refer to “INSTALLING THE REAR
BRAKE”.
Refer to “REMOVING THE BRAKES”
and “INSTALLING THE REAR BRAKE”.
FRONT AND REAR BRAKES
Order
12
13
14
Job/Part
Rear brake cable (lever side)
Rear brake switch
Rear brake lever
Q’ty
1
1
1
CHAS
Remarks
For installation, reverse the removal procedure.
7-8
FRONT AND REAR BRAKES
CHAS
REMOVING THE BRAKES
The following procedure applies to each brake.
1. Remove:
• brake camshaft lever
• brake shoe wear indicator
• brake camshaft
NOTE:
When removing the brake camshaft lever,
mark the position on the brake camshaft lever
where it is aligned with the punch mark in the
brake camshaft.
EBS00439
CHECKING THE BRAKE SHOE PLATES
The following procedure applies to each brake.
1. Check:
• brake shoe plate
• pivot pin
• brake camshaft
Bends/cracks/damage → Replace.
• dust seal
Wear/damage → Replace.
EBS00440
CHECKING THE BRAKE SHOES
The following procedure applies to each brake.
1. Check:
• brake shoes 1
• brake shoe springs 2
Cracks/damage → Replace as a set.
NOTE:
When replacing the brake shoes, replace the
brake shoe springs at the same time.
_
7-9
FRONT AND REAR BRAKES
CHAS
2. Check:
• brake shoe lining surface
Glazed areas → Remove.
Use coarse sandpaper.
NOTE:
After using sandpaper, wipe off the polished
particles with a cloth.
_
3. Measure:
• brake shoe lining thickness a
Out of specification → Replace.
1 Measuring points
NOTE:
Replace the brake shoes as a set if either is
found to be worn to the wear limit.
_
Brake lining thickness
4.0 mm (0.16 in)
<Limit>: 2.0 mm (0.08 in)
È
EBS00441
É
a
a
CHECKING THE BRAKE DRUMS
The following procedure applies to each brake.
1. Measure:
• brake drum inside diameter a
Out of specification → Replace.
Rear brake drum inside diameter
Front: 110.0 mm (4.33 in)
<Limit>: 110.5 mm (4.35 in)
Rear: 130.0 mm (5.12 in)
<Limit>: 130.5 mm (5.14 in)
È Front brake drum
É Rear brake drum
7 - 10
FRONT AND REAR BRAKES
È
É
CHAS
2. Check:
• brake drum inner surface
Oil/scratches → Remove.
Oil
Use a rag soaked in
lacquer thinner or
solvent.
Scratches
Use an emery cloth (light
and even polishing).
È Front brake drum
É Rear brake drum
EBS00442
INSTALLING THE FRONT BRAKES
The following procedure applies to both of the
front brakes.
Reverse the “Removal” procedure.
Note the following points.
1. Lubricate:
• brake camshaft
• pivot pin
Lithium-soap-based grease
CAUTION:
_
È
During installation, lightly grease the brake
camshaft and the pivot pin. Wipe off the
excess grease.
2.
•
•
•
Install:
brake camshaft 1
brake shoe wear indicator 2
brake camshaft lever
T.
R.
NOTE:
• Install the brake camshaft so its punch mark
a is positioned as shown.
• Align the projection on the brake shoe wear
indicator with the notch in the brake camshaft.
• Align the punch mark in the brake camshaft
with the mark on the brake camshaft lever.
_
É
9 Nm (0.9 m · kg, 6.5 ft · lb)
È Left side
É Right side
7 - 11
FRONT AND REAR BRAKES
CHAS
3. Install:
• brake shoe plate 1
NOTE:
When installing the brake shoe plate, align the
groove a of the brake shoe plate with the projection b of the steering knuckle.
_
4. Install:
• front brake cable (drum side)
• brake shoes
NOTE:
Check that the brake shoes are properly positioned.
5. Check:
• brake camshaft operation
Unsmooth operation → Repair.
6. Adjust:
• front brake
Refer to “ADJUSTING THE
BRAKE” in chapter 3.
FRONT
EBS00442
INSTALLING THE REAR BRAKE
Reverse the “Removal” procedure.
Note the following points.
1. Lubricate:
• brake camshaft
• pivot pin
Lithium-soap-based grease
CAUTION:
_
During installation, lightly grease the brake
camshaft and the pivot pin. Wipe off the
excess grease.
7 - 12
FRONT AND REAR BRAKES
2.
•
•
•
CHAS
Install:
brake camshaft 1
brake shoe wear indicator plate 2
brake camshaft lever
T.
R.
9 Nm (0.9 m · kg, 6.5 ft · lb)
NOTE:
• Install the brake camshaft so its punch mark
a is positioned as shown.
• Align the projection on the brake shoe wear
indicator with the notch in the brake camshaft.
• Align the punch mark in the brake camshaft
with the mark on the brake camshaft lever.
_
3. Install:
• rear brake cable (drum side)
• brake shoes
NOTE:
Check that the brake shoes are properly positioned.
4.
•
•
•
Install:
brake drum boss
brake drum
lock washers 1 New
NOTE:
Bend the tabs of each lock washer along a flat
side of each nut.
5. Check:
• brake camshaft operation
Unsmooth operation → Repair.
6. Adjust:
• rear brake
Refer to “ADJUSTING THE REAR BRAKE”.
in chapter 3.
7 - 13
STEERING SYSTEM
CHAS
EBS00444
STEERING SYSTEM
HANDLEBAR
Order
Job/Part
Removing the handlebar
Handlebar cover
Q’ty
1
Handlebar grip
2
2
3
Front brake cable
Front brake lever assembly
2
1
4
5
6
7
8
Handlebar switch
Rear brake cable
Rear brake switch
Rear brake lever
Plastic band
1
1
1
1
1
7 - 14
Remarks
Remove the parts in the order listed.
Refer to “SEAT, FENDERS AND FUEL
TANK” in chapter 3.
Refer to “REMOVING THE HANDLEBAR
GRIPS” and “INSTALLING THE HANDLEBAR GRIPS”.
Refer to “INSTALLING THE FRONT
BRAKE LEVER ASSEMBLY”.
Refer to “INSTALLING THE REAR
BRAKE LEVER”.
STEERING SYSTEM
Order
9
10
11
Job/Part
Upper handlebar holder
Handlebar
Lower handlebar holder
Q’ty
2
1
1
CHAS
Remarks
Refer to “INSTALLING THE HANDLEBAR”.
For installation, reverse the removal procedure.
7 - 15
STEERING SYSTEM
CHAS
EBS00447
REMOVING THE HANDLEBAR GRIPS
1. Remove:
• handlebar grips 1
NOTE:
Blow compressed air between the handlebar
and handlebar grip, and gradually push the
grip off the handlebar.
_
EBS00445
REMOVING THE REAR BRAKE SWITCH
1. Remove:
• rear brake switch 1
NOTE:
Push the fastener when removing the rear
brake switch out of the rear brake lever holder.
_
EBS00448
CHECKING THE HANDLEBAR
1. Check:
• handlebar 1
Bends/cracks/damage → Replace.
WARNING
_
Do not attempt to straighten a bent handlebar as this may dangerously weaken the
handlebar.
7 - 16
STEERING SYSTEM
CHAS
EBS00449
INSTALLING THE HANDLEBAR
1. Install:
• lower handlebar holder
• handlebar
• upper handlebar holders
T.
R.
20 Nm (2.0 m · kg, 14 ft · lb)
NOTE:
• Install the handlebar within 15° from the horizontal line shown in the illustration.
• The upper handlebar holders should be
installed with the punched mark 1 forward
2.
_
CAUTION:
_
First tighten the bolt 3 on the front side of
the handlebar holder, and then tighten the
bolt 4 on the rear side.
EBS00450
INSTALLING THE HANDLEBAR GRIPS
1. Install:
• handlebar grips
NOTE:
• Before installing the handlebar grips, temporarily install the rear brake lever and front
brake lever assembly on the handlebar.
• Before applying the adhesive, wipe off
grease or oil on the handlebar surface with a
lacquer thinner.
_
7 - 17
STEERING SYSTEM
CHAS
EBS00451
INSTALLING THE REAR BRAKE LEVER
1. Install:
• rear brake lever 1
• handlebar switch 2
NOTE:
• Install the rear brake lever within 10° from
the horizontal line shown in the illustration.
• After installing the rear brake lever, make
sure the rear brake lever 1, handlebar
switch 2, and handlebar grip 3 are in the
positions shown in the illustration.
_
2. Adjust:
• rear brake
Refer to “ADJUSTING THE REAR BRAKE”
in chapter 3.
EBS00452
INSTALLING THE FRONT BRAKE LEVER
ASSEMBLY
1. Install:
• front brake lever assembly 1
NOTE:
• Install the front brake lever assembly within
10° from the horizontal line shown in the
illustration.
• After installing the front brake lever assembly, make sure that the clearance a
between the front brake lever assembly 1
and handlebar grip 2 is 9 mm (0.35 in).
_
2. Adjust:
• front brake
Refer to “ADJUSTING
BRAKE” in chapter 3.
7 - 18
THE
FRONT
STEERING SYSTEM
CHAS
EBS00454
STEERING STEM
Order
Job/Part
Removing the steering stem
Front fender
Q’ty
1
Handlebar
Lock washer
1
2
3
4
5
Steering stem bushing
Spacer
Oil seal
Steering stem
2
2
2
1
7 - 19
Remarks
Remove the parts in the order listed.
Refer to “SEAT, FENDERS AND FUEL
TANK” in chapter 3.
Refer to “HANDLEBAR”.
Refer to “INSTALLING THE LOCK
WASHER”.
Refer to “REMOVING THE STEERING
STEM” and “INSTALLING THE STEERING STEM”.
For installation, reverse the removal procedure.
STEERING SYSTEM
CHAS
EBS00455
REMOVING THE STEERING STEM
1. Remove:
• steering stem
NOTE:
When loosening each tie-rod end nut 1, hold
the tie-rod ball joint with a 14-mm wrench 2.
EBS00456
CHECKING THE STEERING STEM
1. Check:
• steering stem
Bends → Replace.
WARNING
_
Do not attempt to straighten a bent stem;
this may dangerously weaken the stem.
2. Check:
• steering stem bushings 1
Wear/damage → Replace.
INSTALLING THE STEERING STEM
1. Tighten:
• steering stem nut 1
T.
R.
35 Nm (3.5 m · kg, 25 ft · lb)
• tie-rod end nut 2
T.
R.
40 Nm (4.0 m · kg, 29 ft · lb)
NOTE:
When tightening each tie-rod end nut 2, hold
the tie-rod ball joint with a 14-mm wrench 3.
EBS00459
INSTALLING THE LOCK WASHER
1. Install:
• lock washer 1 New
NOTE:
Bend a lock washer tab along a flat side of
each bolt.
7 - 20
STEERING SYSTEM
CHAS
EBS00460
TIE-RODS AND STEERING KNUCKLES
Order
Job/Part
Removing the tie-rods and steering
knuckles
Front brakes
Q’ty
1
Tie-rod
1
2
3
4
5
Steering knuckle
Thrust cover
Spacer
Bushing
1
2
1
2
Remarks
Remove the parts in the order listed.
Refer to “FRONT AND REAR BRAKES”.
The following procedure applies to both
of the tie-rods and steering knuckles.
Refer to “REMOVING THE TIE-RODS”
and “INSTALLING THE TIE-RODS”.
For installation, reverse the removal procedure.
7 - 21
STEERING SYSTEM
CHAS
EBS00461
REMOVING THE TIE-RODS
The following procedure applies to both of the
tie-rods.
1. Remove:
• tie-rod 1
NOTE:
When removing the tie-rod, hold each tie-rod
ball joint with a 14-mm wrench 2 and then
loosen the tie-rod end nut.
_
EBS00462
CHECKING THE TIE-RODS
The following procedure applies to both of the
tie-rods.
1. Check:
• tie-rod free play and movement
Free play → Replace the tie-rod end.
Turns roughly → Replace the tie-rod end.
2. Check:
• tie-rod
Bends/damage → Replace.
EBS00464
CHECKING THE STEERING KNUCKLES
The following procedure applies to both of the
steering knuckles.
1. Check:
• steering knuckle
Damage/pitting → Replace.
7 - 22
STEERING SYSTEM
CHAS
EBS00465
T.
INSTALLING THE TIE-RODS
The following procedure applies to both of the
tie-rods.
1. Install:
15 Nm (1.5 m · kg, 11 ft · lb)
• tie-rod
R.
NOTE:
• The tie-rod side which must be installed on
the inside has grooves 1.
• When installing the tie-rod, hold each tie-rod
ball joint with a 14-mm wrench 2 and then
tighten the tie-rod end nut.
_
2. Adjust:
• toe-in
Refer to “ADJUSTING THE TOE-IN” in
chapter 3.
7 - 23
FRONT SHOCK ABSORBER ASSEMBLIES AND FRONT
SWINGARM
CHAS
EBS00468
FRONT SHOCK ABSORBER ASSEMBLIES AND FRONT SWINGARM
Order
1
2
Job/Part
Removing the front shock absorber
assemblies and front swingarm
Steering knuckles
Front shock absorber
Front swingarm
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “STEERING SYSTEM”.
2
1
7 - 24
Refer to “REMOVING THE FRONT
SWINGARM”.
For installation, reverse the removal procedure.
FRONT SHOCK ABSORBER ASSEMBLIES AND FRONT
SWINGARM
CHAS
EBS00469
REMOVING THE FRONT SWINGARM
1. Check:
• front swingarm free play
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Check the front swingarm side play È by
moving it from side to side.
If side play is noticeable, check the bushings.
b. Check the front swingarm vertical movement É by moving it up and down.
If the vertical movement is tight or rough, or
if there is binding, check the bushings.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Remove:
• front swingarm
EBS00470
CHECKING THE FRONT SWINGARM
1. Check:
• front swingarm 1
Bends/damage → Replace.
2. Check:
• bushings 2
Wear/damage → Replace.
EBS00471
CHECKING THE FRONT SHOCK
ABSORBER ASSEMBLIES
1. Check:
• shock absorber rod
Bends/damage → Replace the shock
absorber assembly.
• shock absorber assembly
Oil leaks → Replace the shock absorber
assembly.
• spring
Fatigue → Replace the shock absorber
assembly.
Move the spring up and down.
7 - 25
REAR SHOCK ABSORBER AND REAR SWINGARM
CHAS
EBS00476
REAR SHOCK ABSORBER AND REAR SWINGARM
Order
Job/Part
Removing the rear shock absorber
and swingarm
C.D.I. magneto cover
Rear axle/final drive assembly
Q’ty
Remarks
Remove the parts in the order listed.
Refer to “C.D.I. MAGNETO” in chapter 4.
Refer to “REAR AXLE/FINAL DRIVE
ASSEMBLY AND DRIVE SHAFT” in
chapter 6.
1
2
3
Rear shock absorber
Pivot shaft
Lock washer
1
1
1
4
Rear swingarm
1
5
6
Metal clamp
Dust boot
2
1
Refer to “INSTALLING THE LOCK
WASHER”.
Refer to “REMOVING THE REAR SWINGARM”.
For installation, reverse the removal procedure.
7 - 26
REAR SHOCK ABSORBER AND REAR SWINGARM
CHAS
EBS00477
REMOVING THE REAR SWINGARM
1. Check:
• swingarm free play
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Check the tightening torque of the pivot
shaft.
T.
Pivot shaft
85 Nm (8.5 m · kg, 61 ft · lb)
R.
b. Check the rear swingarm side play È by
moving it from side to side.
If side play is noticeable, check the spacer,
bushings and pivot shaft.
c. Check the rear swingarm vertical movement
É by moving it up and down.
If vertical movement is tight or rough, or if
there is binding, check the bushings, spacer
and pivot shaft.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
2. Remove:
• pivot shaft
• rear swingarm
EBS00478
CHECKING THE REAR SHOCK ABSORBER
1. Check:
• shock absorber
Oil leaks → Replace the shock absorber
assembly.
• shock absorber rod
Bends/damage → Replace the shock
absorber assembly.
• spring
Fatigue → Replace the shock absorber
assembly.
Move the spring up and down.
7 - 27
REAR SHOCK ABSORBER AND REAR SWINGARM
CHAS
EBS00479
CHECKING THE REAR SWINGARM
1. Check:
• rear swingarm
Bends/cracks/damage → Replace.
2. Check:
• bushings
Wear/damage → Replace.
EBS00481
CHECKING THE DUST BOOT
1. Check:
• dust boot 1
Damage → Replace.
INSTALLING THE LOCK WASHER
1. Install:
• lock washer 1 New
NOTE:
Insert the small tab of the lock washer in the
groove on the swingarm, and then bend the
other lock washer tab along a flat side of the
pivot shaft head.
7 - 28
ELECTRICAL COMPONENTS
ELEC
–
+
EBS00500
ELECTRICAL
ELECTRICAL COMPONENTS
1 Main switch
2 Neutral indicator light
3 Rear brake switch
4 Handlebar switch
5 Battery
6 Main fuse
7 Engine stop switch (frame)
8 Rectifier/regulator
9 Diode
0 Starting circuit cut-off relay
A Starter relay
B Neutral switch
C Pickup coil/stator assembly
D Starter motor
E Ignition coil
F C.D.I. unit
G Wire harness
8
8-1
CHECKING SWITCH CONTINUITY
ELEC
–
+
EBS01028
CHECKING SWITCH CONTINUITY
Check each switch for continuity with the
pocket tester. If the continuity reading is incorrect, check the wiring connections and if necessary, replace the switch.
CAUTION:
_
Never insert the tester probes into the coupler terminal slots 1. Always insert the
probes from the opposite end of the coupler, taking care not to loosen or damage
the leads.
Pocket tester
P/N. YU-03112-C, 90890-03112
NOTE:
• Before checking for continuity, set the pocket
tester to “0” and to the “Ω × 1” range.
• When checking for continuity, switch back
and forth between the switch positions a few
times.
_
b
R Br B B/W
a
ON
OFF
The terminal connections for switches (e.g.,
main switch, engine stop switch) are shown in
an illustration similar to the one on the left.
The switch positions a are shown in the far
left column and the switch lead colors b are
shown in the top row in the switch illustration.
B B/W
R Br
NOTE:
“
” indicates a continuity of electricity
between switch terminals (i.e., a closed circuit
at the respective switch position).
_
The example illustration on the left shows
that:
There is continuity between black and black/
white when the switch is set to “OFF”.
There is continuity between red and brown
when the switch is set to “ON”.
8-2
ELEC
CHECKING THE SWITCHES
–
+
EBS01029
CHECKING THE SWITCHES
Check each switch for damage or wear, proper connections, and also for continuity between the terminals. Refer to “CHECKING SWITCH CONTINUITY”.
Damage/wear → Repair or replace.
Improperly connected → Properly connect.
Incorrect continuity reading → Replace the switch.
1
2
R Br B B/W
B B/W
R
ON
OFF
Br
3
Br R/W
Br
B/W B
OFF
ON
RUN
OFF
R/W
4
B
B
B
(BLACK)
Sb
5
6
B
B
(BLACK)
1 Main switch
2 Start switch
3 Engine stop switch (handlebar)
4 Rear brake switch
5 Neutral switch
6 Engine stop switch (frame)
8-3
CHECKING THE BULBS AND BULB SOCKETS
ELEC
–
+
EBS01030
CHECKING THE BULBS AND
BULB SOCKETS
Check each bulb and bulb socket for damage
or wear, proper connections, and also for continuity between the terminals.
Damage/wear → Repair or replace the
bulb, bulb socket or both.
Improperly connected → Properly connect.
No continuity → Repair or replace the bulb,
bulb socket or both.
TYPES OF BULBS
The bulbs used on this machine are shown in
the illustration on the left.
• Bulbs a and b are used for the headlights
and usually use a bulb holder that must be
detached before removing the bulb. The
majority of these types of bulbs can be
removed from their respective socket by
turning them counterclockwise.
• Bulbs c is used for turn signal and tail/
brake lights and can be removed from the
socket by pushing and turning the bulb
counterclockwise.
• Bulbs d and e are used for meter and indicator lights and can be removed from their
respective socket by carefully pulling them
out.
CHECKING THE CONDITION OF THE
BULBS
The following procedure applies to all of the
bulbs.
1. Remove:
• bulb
8-4
CHECKING THE BULBS AND BULB SOCKETS
ELEC
–
+
WARNING
_
Since the headlight bulb gets extremely
hot, keep flammable products and your
hands away from the bulb until it has
cooled down.
CAUTION:
_
• Be sure to hold the socket firmly when
removing the bulb. Never pull the lead,
otherwise it may be pulled out of the terminal in the coupler.
• Avoid touching the glass part of the headlight bulb to keep it free from oil, otherwise the transparency of the glass, the
life of the bulb, and the luminous flux will
be adversely affected. If the headlight
bulb gets soiled, thoroughly clean it with
a cloth moistened with alcohol or lacquer
thinner.
2. Check:
• bulb (for continuity)
(with the pocket tester)
No continuity → Replace.
Pocket tester
P/N. YU-03112-C, 90890-03112
NOTE:
Before checking for continuity, set the pocket
tester to “0” and to the “Ω × 1” range.
_
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the positive tester probe to terminal 1 and the negative tester probe to terminal 2, and check the continuity.
b. Connect the positive tester probe to terminal 1 and the negative tester probe to terminal 3, and check the continuity.
c. If either of the readings indicate no continuity, replace the bulb.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
8-5
CHECKING THE BULBS AND BULB SOCKETS
ELEC
–
+
CHECKING THE CONDITION OF THE BULB
SOCKETS
The following procedure applies to all of the
bulb sockets.
1. Check:
• bulb socket (for continuity)
(with the pocket tester)
No continuity → Replace.
Pocket tester
P/N. YU-03112-C, 90890-03112
NOTE:
Check each bulb socket for continuity in the
same manner as described in the bulb section;
however, note the following.
_
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Install a good bulb into the bulb socket.
b. Connect the pocket tester probes to the
respective leads of the bulb socket.
c. Check the bulb socket for continuity. If any
of the readings indicate no continuity,
replace the bulb socket.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
8-6
ELEC
IGNITION SYSTEM
–
+
EBS00503
IGNITION SYSTEM
CIRCUIT DIAGRAM
G/Y W/L
O B/R B/W
B W/R
(BLACK)
B/R G/W
G/W B/R
W/R W/L
W/L W/R
(GRAY)
(GRAY)
Sb W
W Sb
B Y/R
Y/R B
1
B/R
B/R
G/W
G/W
W/R
W/R
W/L
W/L
O
O
B
C
B
D
Sb
W
W
Y/R
Y/R
R
4
B/W
Sb
G/Y
B
R
Y/R
B
Sb
Sb G/W
(BLACK)
Sb
B
W
Y
R
W
B
5A
2
B
5
R
R Y/R
R
6
L/W
L/W
R/W
R
B
R
L/W
R
9
R
R
7
3
B/W B
Br
R
B B/W
R
B
ON
OFF
B
L/W
B
B
8
B/Y L/W
Sb R/W
B
0
(BLACK)
A
Br
Br B B/W
R/W
B
R/W
Sb
B/Y
B
B/W
B/W
B/Y
H
G/Y
E
I
G
J
OFF
ON
RUN
OFF
Br
Br
R/W
R/W
B
B
B
B/Y
B
(BLACK)
G/Y
B
B/W B
Br
B
(BLACK)
Br
G/Y
F
K
B
B
(BLACK)
B
G/Y B
Sb
(BLACK)
8-7
1 C.D.I. magneto
3 Main switch
B C.D.I. unit
C Ignition coil
D Spark plug
G Engine stop
switch (frame)
J Engine stop
switch (handlebar)
IGNITION SYSTEM
EBS01045
ELEC
–
+
EBS01032
TROUBLESHOOTING
1. Spark plug
The ignition system fails to operate (no
spark or intermittent spark).
• Check the condition of the spark plug.
• Check the spark plug type.
• Measure the spark plug gap.
Refer to “CHECKING THE SPARK PLUG”
in chapter 3.
Check:
1. spark plug
2. ignition spark gap
3. spark plug cap resistance
4. ignition coil resistance
5. main switch
6. engine stop switches
7. pickup coil resistance
8. source coil resistance
9. wiring connections (of the entire ignition
system)
Standard spark plug
CR7HS (NGK)
Spark plug gap
0.6 ~ 0.7 mm (0.024 ~ 0.028 in)
• Is the spark plug in good condition, is it of
the correct type, and is its gap within specification?
YES
NOTE:
• Before troubleshooting, remove the following
part(s):
1. seat
2. front fender
3. fuel tank
• Troubleshoot with the following special
tool(s).
NO
_
Re-gap or replace
the spark plug.
Dynamic spark tester
P/N. YM-34487
Ignition checker
P/N. 90890-06754
Pocket tester
P/N. YU-03112-C, 90890-03112
8-8
IGNITION SYSTEM
EBS01034
ELEC
–
+
EBS01036
2. Ignition spark gap
3. Spark plug cap resistance
• Disconnect the spark plug cap from the
spark plug.
• Connect the ignition dynamic spark tester
1 as shown.
• Remove the spark plug cap from the spark
plug lead.
• Connect the pocket tester (“Ω × 1k” range)
to the spark plug cap as shown.
2 Spark plug cap
3 Spark plug
• Set the main switch to “ON”.
• Measure the ignition spark gap a.
• Crank the engine by pushing the starter
switch and gradually increase the spark
gap until a misfire occurs.
• Measure the spark plug cap resistance.
Spark plug cap resistance
10 kΩ at 20 °C (68 °F)
• Is the spark plug cap OK?
NO
YES
Minimum ignition spark gap
6 mm (0.24 in)
Replace the
plug cap.
• Is there a spark and is the spark gap within
specification?
NO
YES
The ignition system
is OK.
8-9
spark
EBS01038
–
ELEC
IGNITION SYSTEM
+
EBS01041
4. Ignition coil resistance
5. Main switch
• Disconnect the ignition coil connectors
from the ignition coil terminals.
• Connect the pocket tester (Ω × 1) to the
ignition coil as shown.
• Check the main switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the main switch OK?
NO
YES
Positive tester probe → orange terminal
Negative tester probe → ignition coil base
Replace
switch.
the
main
EBS01042
6. Engine stop switches
• Check the engine stop switches for continuity.
Refer to “CHECKING THE SWITCHES”.
• Are the engine stop switches OK?
• Measure the primary coil resistance.
YES
Primary coil resistance
0.18 ~ 0.28 Ω at 20 °C (68 °F)
• Connect the pocket tester (Ω × 1k) to the
ignition coil as shown.
Positive tester probe → orange terminal
Negative tester probe → spark plug lead
• Measure the secondary coil resistance.
Secondary coil resistance
6.32 ~ 9.48 kΩ at 20 °C (68 °F)
• Is the ignition coil OK?
YES
NO
Replace the ignition
coil.
8 - 10
NO
Replace the handlebar switch or engine
stop switch (frame).
ELEC
IGNITION SYSTEM
EBS01040
–
+
EBS01099
7. Pickup coil resistance
8. Source coil resistance
• Disconnect the C.D.I. magneto coupler
from the wire harness.
• Connect the pocket tester (Ω × 100) to the
pickup coil terminal as shown.
• Disconnect the C.D.I. magneto coupler
from the wire harness.
• Connect the pocket tester (Ω × 100) to the
source coil terminal.
Positive tester probe →
white/red terminal 1
Negative tester probe →
white/blue terminal 2
Positive tester probe →
black/red terminal 1
Negative tester probe →
green/white terminal 2
2
1
G/W B/R
G/W B/R
W/L W/R
W/L W/R
2
1
• Measure the pickup coil resistance.
• Measure the source coil resistance.
Pickup coil resistance
264 ~ 396 Ω at 20 °C (68 °F)
(between white/red and white/
blue)
Source coil resistance
304 ~ 456 Ω at 20 °C (68 °F)
(black/red and green/white)
YES
• Is the pickup coil OK?
YES
NO
NO
Replace the pickup
coil/stator assembly.
Replace the pickup
coil/stator assembly.
EBS01047
9. Wiring
• Check the entire ignition system’s wiring.
Refer to “CIRCUIT DIAGRAM”.
• Is the ignition system’s wiring properly
connected and without defects?
YES
Replace the C.D.I.
unit.
8 - 11
NO
Properly connect or
repair the ignition
system’s wiring.
ELEC
ELECTRIC STARTING SYSTEM
–
+
EBS00506
ELECTRIC STARTING SYSTEM
CIRCUIT DIAGRAM
B/R G/W
G/W B/R
W/R W/L
W/L W/R
(GRAY)
(GRAY)
Sb W
W Sb
B Y/R
Y/R B
B/R
G/W
1
W/R
W/L
Sb
W
W
Y/R
Y/R
R
4
B/W
Sb
G/Y
B
R
Y/R
B
Sb
2 Neutral switch
3 Main switch
5 Main fuse
6 Positive battery lead
7 Battery
8 Negative battery lead
G/Y W/L
O B/R B/W
9 Starter relay B W/R Sb G/W
0 Starter motor
(BLACK) (BLACK)
A Starting circuit cut-off relay
O
E Diode B/R
G/W
B
F Rear brake
switch
W/R
W/L
I Start switch
Sb
2
B
W
Y
R
W
B
5A
B
5
R
R Y/R
R
6
L/W
L/W
R/W
R
B
R
L/W
R
9
R
R
7
3
B/W B
Br
R
B B/W
R
B
ON
OFF
B
L/W
B
B
8
B/Y L/W
Sb R/W
B
0
(BLACK)
A
Br
Br B B/W
R/W
B
R/W
Sb
B/Y
B
B/W
B/W
B/Y
H
I
OFF
ON
B
G
J
RUN
OFF
Br
Br
R/W
R/W
B
B
(BLACK)
G/Y
E
B
B/Y
G/Y
B
B/W B
Br
B
(BLACK)
Br
G/Y
F
K
B
B
(BLACK)
B
G/Y B
Sb
(BLACK)
8 - 12
O
B
ELECTRIC STARTING SYSTEM
ELEC
–
+
EBS00507
STARTING CIRCUIT OPERATION
The starting circuit on this model consists of
the starter motor, starter relay, starting circuit
cut-off relay, rear brake switch and neutral
switch. If the main switch is on and the engine
stop switch is in the RUN position, the starter
motor can be operated only if:
1
È
R
• The transmission is in neutral (the neutral
switch is closed).
or
• You pull in the rear brake lever (the rear
brake switch is ON).
2
L/W
3
1 Main fuse
2 Battery
3 Starter relay
4 Starter motor
5 Starting circuit cut-off relay
6 Diode
7 Rear brake switch
8 Start switch
9 Neutral switch
B
4
5
B/Y
È TO MAIN SWITCH
É FROM MAIN SWITCH
6
G/Y
Sb
R/W
7
8
9
Br
B
É
8 - 13
ELECTRIC STARTING SYSTEM
EBS01050
ELEC
–
+
EBS01044
TROUBLESHOOTING
2. Battery
The starter motor fails to turn.
• Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in chapter 3.
Check:
1. main fuse
2. battery
3. starter motor
4. starting circuit cut-off relay
5. starter relay
6. main switch
7. neutral switch
8. rear brake switch
9. start switch
10.diode
11.wiring connections
(of the entire starting system)
Specific gravity
1.280 at 20 °C (68 °F)
• Is the battery OK?
NO
YES
NOTE:
• Before troubleshooting, remove the following
part(s):
1. seat
2. front fender
3. rear fender
4. C.D.I. magneto cover
• Troubleshoot with the following special
tool(s).
• Refill battery fluid.
• Clean the battery
terminals.
• Recharge or
replace the battery.
_
EBS01051
3. Starter motor
• Connect the positive battery terminal 1
and starter motor lead 2 with a jumper
lead 3.
Pocket tester
P/N. YU-03112-C, 90890-03112
EBS01043
1. Main fuse
• Check the main fuse for continuity.
Refer to “CHECKING THE FUSE” in chapter 3.
• Is the main fuse OK?
YES
NO
Replace the fuse.
WARNING
_
• A wire that is used as a jumper lead
must have at least the same capacity or
more as that of the battery lead, otherwise the jumper lead may burn.
• This check is likely to produce sparks,
therefore make sure nothing flammable
is in the vicinity.
• Does the starter motor turn?
YES
NO
Repair or replace the
starter motor.
8 - 14
ELECTRIC STARTING SYSTEM
EBS01053
Positive battery terminal → red/white 1
Negative battery terminal →
black/yellow 2
Positive tester probe → red/white 1
Negative tester probe → blue/white 3
–
+
Second step:
• Connect the pocket tester (Ω × 1) to the
starting circuit cut-off relay coupler as
shown.
• Measure the starting circuit cut-off relay for
continuity as follows.
4. Starting circuit cut-off relay
First step:
• Disconnect the starting circuit cut-off relay
coupler from the wire harness.
• Connect the pocket tester (Ω × 1) and battery (12 V) to the starting circuit cut-off
relay coupler as shown.
ELEC
Positive tester probe →
sky blue 4
Continuity
Negative tester probe →
black/yellow 5
Positive tester probe →
black/yellow 5 No
continuity
Negative tester probe →
sky blue 4
1
2
4
5
3
B/Y
L/W
Sb
R/W
• Does the starting circuit cut-off relay have
continuity between red/white and blue/
white?
B/Y
L/W
Sb
R/W
NOTE:
When you switch the tester’s positive and
negative probes, the readings in the above
chart will be reversed.
_
• Are the testing readings correct?
YES
NO
Replace the starting
circuit cut-off relay.
8 - 15
ELECTRIC STARTING SYSTEM
EBS01054
ELEC
–
+
EBS01046
5. Starter relay
7. Neutral switch
• Disconnect the starter relay coupler from
the coupler.
• Connect the pocket tester (Ω × 1) and battery (12 V) to the starter relay coupler as
shown.
• Check the neutral switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the neutral switch OK?
YES
Positive battery terminal → blue/white 1
Negative battery terminal → red/white 2
NO
Replace the neutral
switch.
Positive tester probe → red 3
Negative tester probe → black 4
8. Rear brake switch
3
R
• Check the rear brake switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the rear brake switch OK?
1
L/W
R/W
YES
2
NO
B
4
Replace the
brake switch.
• Does the starter relay have continuity
between red and black?
rear
EBS01057
9. Start switch
NO
YES
Replace the starter
relay.
• Check the start switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the start switch OK?
YES
NO
EBS01041
6. Main switch
Replace the handlebar switch.
• Check the main switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the main switch OK?
NO
YES
Replace
switch.
the
main
8 - 16
ELECTRIC STARTING SYSTEM
EBS01060
ELEC
–
+
EBS01059
10.Diode
11.Wiring
• Remove the diode from the coupler.
• Connect the pocket tester (Ω × 1) to the
diode terminals as shown.
• Check the diode for continuity as follows.
Positive tester probe →
green/yellow 1
Continuity
Negative tester probe →
black/yellow 2
• Check the entire starting system’s wiring.
Refer to “CIRCUIT DIAGRAM”.
• Is the starting system’s wiring properly
connected and without defects?
YES
The starting system
circuit is OK.
Positive tester probe →
black/yellow 2 No
continuity
Negative tester probe →
green/yellow 1
1
G/Y
B/Y
2
NOTE:
When you switch the tester’s positive and
negative probes, the readings in the above
chart will be reversed.
_
• Are the testing readings correct?
YES
NO
Replace the diode.
8 - 17
NO
Properly connect or
repair the starting
system’s wiring.
STARTER MOTOR
ELEC
–
+
EBS01061
STARTER MOTOR
Order
1
2
3
1
2
3
4
Job/Part
Removing the starter motor
Starter motor lead
Ground lead
Starter motor
Disassembling the starter motor
Yoke
Armature coil
Brush
Bracket
Q’ty
Remarks
Remove the parts in the order listed.
1
1
1
For installation, reverse the removal procedure.
Remove the parts in the order listed.
1
1
1
1
Refer to “ASSEMBLING THE STARTER
MOTOR”.
For assembly, reverse the disassembly
procedure.
8 - 18
STARTER MOTOR
ELEC
–
+
EBS01064
CHECKING THE STARTER MOTOR
1. Check:
• commutator
Dirt → Clean with 600-grit sandpaper.
2. Measure:
• commutator diameter a
Out of specification → Replace the starter
motor.
Commutator wear limit
15.5 mm (0.61 in)
3. Measure:
• mica undercut a
Out of specification → Scrape the mica to
the proper measurement with a hacksaw
blade that has been grounded to fit the
commutator.
Mica undercut
1 mm (0.04 in)
NOTE:
The mica of the commutator must be undercut
to ensure proper operation of the commutator.
_
4. Measure:
• armature assembly resistances
(commutator and insulation)
Out of specification → Replace the starter
motor.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Measure the armature assembly resistances with the pocket tester.
Pocket tester
P/N. YU-03112-C, 90890-03112
Armature coil
Commutator resistance 1
0.029 ~ 0.035 Ω at 20 °C (68 °F)
Insulation resistance 2
Above 1 MΩ at 20 °C (68 °F)
b. If any resistance is out of specification,
replace the starter motor.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
8 - 19
STARTER MOTOR
ELEC
–
+
5. Measure:
• brush length a
Out of specification → Replace the brushes
as a set.
Brush length wear limit
3.5 mm (0.14 in)
a
6. Measure:
• brush spring force
Out of specification → Replace the brush
springs as a set.
Brush spring force
3.24 ~ 4.22 N
(320 ~ 430 gf, 11.66 ~ 15.19 oz)
7. Check:
• gear teeth
Damage/wear → Replace the gear.
8. Check:
• bearing
• oil seal
• O-rings
Damage/wear → Replace the defective
part(s).
EBS00515
ASSEMBLING THE STARTER MOTOR
1. Install:
• bracket
• brush
• armature coil
• yoke
NOTE:
Align the projection a on the yoke with the slot
b on the bracket.
_
8 - 20
–
ELEC
CHARGING SYSTEM
+
EBS00516
CHARGING SYSTEM
CIRCUIT DIAGRAM
B/R G/W
G/W B/R
W/R W/L
W/L W/R
(GRAY)
1
(GRAY)
Sb W
W Sb
B Y/R
Y/R B
Sb
B/R
B/R
G/W
G/W
W/R
W/R
W/L
W/L
W
W
Y/R
Y/R
R
Y/R
B
Sb
R
4
Sb
2
B
W
Y
R
5
5A
B
W
R
B
R Y/R
R
6
R
L/W
L/W
R/W
B
R
L/W
R
9
R
R
7
3
B/W B
Br
R
B B/W
R
ON
OFF
B
L/W
B
B
B
8
B/Y
Sb
B
0
(BL
A
Br
Br B B/W
R/W
B
R/W
Sb
B
B/W
B/W
H
I
G
J
OFF
ON
RUN
OFF
Br
Br
R/W
R/W
B
B
B
B
(BLACK)
B
B/W B
Br
B
(BLACK)
Br
F
K
1 C.D.I. magneto
4 Rectifier/regulator
5 Main fuse
6 Positive battery lead
7 Battery
8 Negative battery lead
Sb
8 - 21
CHARGING SYSTEM
EBS01065
ELEC
–
+
EBS01043
TROUBLESHOOTING
1. Main fuse
The battery is not being charged.
• Check the main fuse for continuity.
Refer to “CHECKING THE FUSE” in chapter 3.
• Is the main fuse OK?
Check:
1. main fuse
2. battery
3. charging voltage
4. charging coil resistance
5. wiring connections
(of the entire charging system)
Replace the fuse.
NOTE:
• Before troubleshooting, remove the following
part(s):
1. seat
2. rear fender
• Troubleshoot with the following special
tool(s).
_
NO
YES
EBS01044
2. Battery
Inductive self-powered tachometer
P/N. YU-8036-B
Engine tachometer
P/N. 90890-03113
Pocket tester
P/N. YU-03112-C, 90890-03112
• Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in chapter 3.
Specific gravity
1.280 at 20 °C (68 °F)
• Is the battery OK?
YES
NO
• Refill battery fluid.
• Clean the battery
terminals.
• Recharge or
replace the battery.
8 - 22
CHARGING SYSTEM
EBS01066
ELEC
–
+
EBS01100
3. Charging voltage
4. Charging coil resistance
• Connect the engine tachometer to the
spark plug lead.
• Connect the pocket tester (DC 20 V) to the
battery as shown.
Positive tester probe →
positive battery terminal
Negative tester probe →
negative battery terminal
• Disconnect the C.D.I. magneto coupler
from the wire harness.
• Connect the pocket tester (Ω × 1) to the
charging coils.
Positive tester probe → white terminal 1
Negative tester probe → black terminal 2
1
W Sb
Y/R B
2
• Measure the charging coil resistance.
Charging coil resistance
0.72 ~ 1.08 Ω at 20 °C (68 °F)
(between white and black)
• Start the engine and let it run at approximately 5,000 r/min.
• Measure the charging voltage.
YES
Charging voltage
14 V at 5,000 r/min
Replace the rectifier/
regulator.
NOTE:
Make sure the battery is fully charged.
_
NO
Replace the pickup
coil/stator assembly.
EBS01059
• Is the charging voltage within specification?
NO
5. Wiring
• Check the entire charging system’s wiring.
Refer to “CIRCUIT DIAGRAM”.
• Is the charging system’s wiring properly
connected and without defects?
YES
The charging circuit
is OK.
YES
The charging system
circuit is OK.
8 - 23
NO
Properly connect or
repair the charging
system’s wiring.
–
ELEC
SIGNAL SYSTEM
+
EBS00521
SIGNAL SYSTEM
CIRCUIT DIAGRAM
O B/R B/W
B W/R
(BLACK)
B/R G/W
G/W B/R
W/R W/L
W/L W/R
(GRAY)
1
(GRAY)
Sb W
W Sb
B Y/R
Y/R B
Sb
B/R
B/R
G/W
G/W
W/R
W/R
W/L
W/L
W
W
Y/R
Y/R
B/W
S
G/Y
R
Y/R
B
Sb
B
R
4
(B
Sb
2
B
W
Y
R
W
B
5A
B
5
R
R Y/R
R
6
L/W
L/W
R/W
R
B
R
L/W
R
9
R
R
7
3
B/W B
Br
R
B B/W
R
B
ON
OFF
B
L/W
B
B
8
B/Y L/W
Sb R/W
B
0
(BLACK)
A
Br
Br B B/W
R/W
B
R/W
Sb
B/Y
B
B/W
B/W
B/Y
H
G/Y
E
I
G
J
OFF
ON
RUN
OFF
Br
Br
R/W
R/W
B
B
B
B/Y
B
(BLACK)
G/Y
B
B/W B
Br
B
(BLACK)
Br
G/Y
F
K
B
B
2 Neutral switch
3 Main switch
B
5 Main fuse
G/Y B
6 Positive battery lead
(BLACK)
7 Battery
8 Negative battery lead
K Neutral indicator light
(BLACK)
Sb
8 - 24
SIGNAL SYSTEM
EBS01073
–
ELEC
+
EBS01044
TROUBLESHOOTING
2. Battery
If the neutral indicator light fails to come
on.
• Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in chapter 3.
Check:
1. main fuse
2. battery
3. main switch
4. wiring connections
(of the entire signaling system)
Specific gravity
1.280 at 20 °C (68 °F)
• Is the battery OK?
NO
YES
NOTE:
• Before troubleshooting, remove the following
part(s):
1. seat
2. front fender
3. C.D.I. magneto cover
• Troubleshoot with the following special
tool(s).
_
• Refill battery fluid.
• Clean the battery
terminals.
• Recharge or
replace the battery.
EBS01041
3. Main switch
Pocket tester
P/N. YU-03112-C, 90890-03112
• Check the main switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the main switch OK?
EBS01043
1. Main fuse
NO
YES
• Check the main fuse for continuity.
Refer to “CHECKING THE FUSE” in chapter 3.
• Is the main fuse OK?
Replace
switch.
the
main
EBS01074
YES
NO
4. Wiring
• Check the entire signal system’s wiring.
Refer to “CIRCUIT DIAGRAM”.
• Is the signaling system’s wiring properly
connected and without defects?
Replace the fuse.
YES
Check the condition
of each of the signaling system’s circuits.
Refer to “CHECKING THE SIGNALING SYSTEM”.
8 - 25
NO
Properly connect or
repair the signaling
system’s wiring.
SIGNAL SYSTEM
EBS01075
EBS01077
+
• Connect the pocket tester (DC 20 V) to the
neutral indicator light connectors (wire harness side) as shown.
1. The neutral indicator light fails to come on.
1. Neutral indicator light bulb and socket
• Check the neutral indicator light bulb and
socket for continuity.
Refer to “CHECKING THE BULBS AND
BULB SOCKETS”.
• Are the neutral indicator light bulb and
socket OK?
Positive tester probe → brown 1
Negative tester probe → sky blue 2
2
1
Sb
Br
NO
DC 20 V
Replace the neutral
indicator light bulb,
socket or both.
• Set the main switch to “ON”.
• Measure the voltage (DC 12 V).
• Is the voltage within specification?
2. Neutral switch
• Check the neutral switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the neutral switch OK?
YES
This circuit is OK.
YES
–
3. Voltage
CHECKING THE SIGNALING SYSTEM
YES
ELEC
NO
Replace the neutral
switch.
8 - 26
NO
The wiring circuit
from the main switch
to the neutral indicator light connectors is
faulty and must be
repaired.
STARTING FAILURE/HARD STARTING
TRBL
SHTG
EBS00537
TROUBLESHOOTING
NOTE:
The following troubleshooting does not cover all the possible causes of trouble. It should be helpful,
however, as a guide to troubleshooting. Refer to the relative procedure in this manual for check,
adjustment and replacement of parts.
_
STARTING FAILURE/HARD STARTING
ELECTRICAL SYSTEM
Spark plug
• Improper plug gap
• Worn electrodes
• Wire between terminals broken
• Improper heat range
• Faulty spark plug cap
Ignition coil
• Broken or shorted primary/secondary
• Faulty spark plug lead
• Broken body
C.D.I. system
• Faulty C.D.I. unit
• Faulty pickup coil
• Faulty source coil
• Broken woodruff key
Switches and wiring
• Faulty main switch
• Faulty engine stop switch
• Broken or shorted wiring
• Faulty neutral switch
• Faulty start switch
Starter motor
• Faulty starter motor
• Faulty starter relay
• Faulty starter circuit cut-off relay
Battery
• Faulty battery
FUEL SYSTEM
Fuel tank
• Empty
• Clogged fuel filter
• Clogged fuel strainer
• Clogged fuel breather hose
• Deteriorated or contaminated fuel
Fuel cock
• Clogged fuel hose
Carburetor
• Deteriorated or contaminated fuel
• Clogged pilot jet
• Clogged pilot air passage
• Sucked-in air
• Deformed float
• Worn needle valve
• Improperly sealed valve seat
• Improperly adjusted fuel level
• Improperly set pilot jet
Air filter
• Clogged air filter element
9
9-1
STARTING FAILURE/HARD STARTING/POOR IDLE SPEED
PERFORMANCE/POOR MEDIUM AND HIGH-SPEED PERFORMANCE
COMPRESSION SYSTEM
Cylinder and cylinder head
• Loose spark plug
• Loose cylinder head or cylinder
• Broken cylinder head gasket
• Broken cylinder gasket
• Worn, damaged or seized cylinder
Valve, camshaft and crankshaft
• Improperly sealed valve
• Improperly contacted valve and valve seat
• Improper valve timing
• Broken valve spring
• Seized camshaft
• Seized crankshaft
TRBL
SHTG
Piston and piston rings
• Improperly installed piston ring
• Worn, fatigued or broken piston ring
• Seized piston ring
• Seized or damaged piston
Crankcase and crankshaft
• Improperly seated crankcase
• Seized crankshaft
Valve train
• Improperly adjusted valve clearance
• Improperly adjusted valve timing
EBS00538
POOR IDLE SPEED PERFORMANCE
POOR IDLE SPEED PERFORMANCE
Carburetor
• Loose pilot jet
• Clogged pilot jet
• Clogged pilot air jet
• Improperly adjusted idle speed (throttle stop
screw)
• Improper throttle cable play
• Flooded carburetor
Electrical system
• Faulty battery
• Faulty spark plug
• Faulty C.D.I. unit
• Faulty pickup coil
• Faulty source coil
• Faulty ignition coil
Valve train
• Improperly adjusted valve clearance
Air filter
• Clogged air filter element
EBS00539
POOR MEDIUM AND HIGH-SPEED PERFORMANCE
POOR MEDIUM AND HIGH-SPEED PERFORMANCE
Refer to “STARTING FAILURE/HARD STARTING” and “POOR IDLE SPEED PERFORMANCE—
Valve train”.
Carburetor
Air filter
• Improper jet needle clip position
• Clogged air filter element
• Improperly adjusted fuel level
• Clogged or loose main jet
• Deteriorated or contaminated fuel
9-2
FAULTY DRIVE TRAIN
TRBL
SHTG
EBS00540
FAULTY DRIVE TRAIN
The following conditions may indicate damaged shaft drive components:
Symptoms
Possible Causes
1. A pronounced hesitation or “jerky” movement during acceleration, deceleration, or
sustained speed. (This must not be confused with engine surging or transmission
characteristics.)
2. A “rolling rumble” noticeable at low speed; a
high-pitched whine; a “clunk” from a shaft
drive component or area.
3. A locked-up condition of the shaft drive
mechanism, no power transmitted from the
engine to the rear wheels.
A. Bearing damage.
B. Improper gear lash.
C. Gear tooth damage.
D. Broken drive shaft.
E. Broken gear teeth.
F. Seizure due to lack of lubrication.
G. Small foreign objects lodged between the
moving parts.
NOTE:
Areas A, B, and C above may be extremely difficult to diagnose. The symptoms are quite subtle and
difficult to distinguish from normal machine operating noise. If there is reason to believe these components are damaged, remove the components and check them.
_
9-3
FAULTY GEAR SHIFTING/CLUTCH SLIPPING/
DRAGGING/OVERHEATING
TRBL
SHTG
EBS00541
FAULTY GEAR SHIFTING
HARD SHIFTING
Refer to “CLUTCH SLIPPING/DRAGGING—CLUTCH DRAGGING”.
JUMPS OUT GEAR
SHIFT LEVER DOES NOT MOVE
Shift shaft
Shift shaft
• Improperly adjusted shift shaft position
• Bent shift shaft
Shift cam, shift forks
• Improperly returned stopper lever
Shift forks
• Groove jammed with impurities
• Worn shift fork
• Seized shift fork
Shift
drum
• Bent shift fork guide bar
Transmission
• Improper thrust play
• Worn shift drum groove
• Seized transmission gear
Transmission
• Jammed impurities
• Worn gear dog
• Incorrectly assembled transmission
EBS00545
CLUTCH SLIPPING/DRAGGING
CLUTCH DRAGGING
Clutch
• Warped pressure plate
• Unevenly tensioned clutch springs
• Loose clutch boss nut
• Bent clutch plate
• Swollen friction plate
• Broken clutch boss
Engine oil
• High oil level
• Improper quality (high viscosity)
• Deterioration
CLUTCH SLIPPING
Clutch
• Loose clutch spring
• Fatigued clutch spring
• Worn friction plate
• Worn clutch plate
• Incorrectly assembled clutch
Engine oil
• Low oil level
• Improper quality (low viscosity)
• Deterioration
EBS00546
OVERHEATING
OVERHEATING
Ignition system
• Improper spark plug gap
• Improper spark plug heat range
• Faulty C.D.I. unit
Fuel system
• Improper carburetor main jet (improper setting)
• Improper fuel level
• Clogged air filter element
Compression system
• Heavy carbon build-up
Engine oil
• Improper oil level
• Improper oil viscosity
• Inferior oil quality
Brake
• Brake drag
9-4
FAULTY BRAKE/SHOCK ABSORBER MALFUNCTION/
UNSTABLE HANDLING
TRBL
SHTG
EBS00549
FAULTY BRAKE
POOR BRAKING EFFECT
Front and rear drum brake
• Worn brake shoe lining
• Worn brake drum
• Oily or greasy brake shoe lining
• Oily or greasy brake drum
• Improperly adjusted brake lever free play
• Improper brake cam lever position
• Improper brake shoe position
• Fatigued/damaged return spring
• Broken brake cable
EBS00551
SHOCK ABSORBER MALFUNCTION
MALFUNCTION
• Bent or damaged damper rod
• Damaged oil seal lip
• Fatigued shock absorber spring
EBS00552
UNSTABLE HANDLING
UNSTABLE HANDLING
Handlebar
• Improperly installed or bent
Steering
• Incorrect toe-in
• Bent steering stem
• Improperly installed steering stem
• Damaged bearing or bearing race
• Bent tie rods
• Deformed steering knuckles
Tires
• Uneven tire pressures on both sides
• Incorrect tire pressure
• Uneven tire wear
Wheels
• Deformed wheel
• Loose bearing
• Bent or loose wheel axle
• Excessive wheel runout
Frame
• Bent
• Damaged frame
Swingarm
• Worn bearing or bushing
• Bent or damaged
9-5
YAMAHA MOTOR CO., LTD.
2500 SHINGAI IWATA SHIZUOKA JAPAN
PRINTED IN U.S.A.
YFM50S WIRING DIAGRAM
G/Y W/L
O B/R B/W
B W/R
(BLACK)
B/R G/W
G/W B/R
W/R W/L
W/L W/R
(GRAY)
(GRAY)
Sb W
W Sb
B Y/R
Y/R B
1
B/R
B/R
G/W
G/W
W/R
W/R
W/L
W/L
(BLACK)
O
O
B
C
B
D
Sb
W
W
Y/R
Y/R
R
4
B/W
Sb
G/Y
B
R
Y/R
B
Sb
Sb G/W
Sb
W
R
W
B
5A
2
B
Y
B
5
R
R Y/R
R
6
R
L/W
L/W
R/W
B
R
L/W
R
9
R
R
7
3
B/W B
Br
R
B B/W
R
B
ON
OFF
B
B/Y L/W
Sb R/W
B
L/W
B
B
8
(BLACK)
COLOR CODE
A
Br
Br B B/W
R/W
B
R/W
Sb
B/Y
B
B/W
B/W
B/Y
H
G/Y
E
I
G
J
OFF
ON
RUN
OFF
Br
Br
R/W
R/W
B
B
B
B/Y
B
(BLACK)
G/Y
B
B/W B
Br
B
(BLACK)
Br
G/Y
F
K
1 C.D.I. magneto
2 Neutral switch
3 Main switch
4 Rectifier/regulator
5 Main fuse
6 Positive battery lead
7 Battery
8 Negative battery lead
9 Starter relay
0 Starter motor
A Starting circuit cut-off relay
B C.D.I. unit
C Ignition coil
D Spark plug
E Diode
F Rear brake switch
G Engine stop switch (frame)
H Handlebar switch
I Start switch
J Engine stop switch (handlebar)
K Neutral indicator light
B
B
(BLACK)
B
G/Y B
Sb
(BLACK)
B ........... Black
Br .......... Brown
O ........... Orange
R ........... Red
Sb ......... Sky blue
W .......... White
Y ........... Yellow
B/R........ Black/Red
B/W ....... Black/White
B/Y ........ Black/Yellow
G/W....... Green/White
G/Y........ Green/Yellow
L/W ....... Blue/White
R/W....... Red/White
W/L ....... White/Blue
W/R....... White/Red
Y/R........ Yellow/Red