STARTER CLUTCH AND GENERATOR5-35 . . . . . . . . . . . . . . . . . . . . . . . . .
STATOR COIL ASSEMBLY 5-35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
STARTER CLUTCH 5-37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE GENERATOR 5-38. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE STARTER CLUTCH 5-39. . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE DAMPER 5-39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE STARTER CLUTCH 5-40. . . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE STARTER CLUTCH 5-41. . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE GENERATOR 5-41. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CRANKSHAFT POSITION SENSOR5-43 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE CRANKSHAFT POSITION SENSOR 5-44. . . . . . . . .
INSTALLING THE CRANKSHAFT POSITION SENSOR 5-44. . . . . . . .
CLUTCH5-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CLUTCH COVER 5-46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PULL LEVER SHAFT 5-47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CLUTCH 5-48. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE CLUTCH 5-50. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE FRICTION PLATES 5-52. . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CLUTCH PLATES 5-52. . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CLUTCH SPRINGS 5-53. . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CLUTCH HOUSING 5-53. . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CLUTCH BOSS 5-53. . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE PRESSURE PLATE 5-54. . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE PULL LEVER SHAFT AND PULL ROD 5-54. . . . . . .
INSTALLING THE CLUTCH 5-54. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SHIFT SHAFT5-58 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SHIFT SHAFT AND STOPPER LEVER 5-58. . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE SHIFT SHAFT 5-60. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE SHIFT SHAFT 5-61. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE STOPPER LEVER 5-61. . . . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE SHIFT SHAFT 5-61. . . . . . . . . . . . . . . . . . . . . . . . . . . .
OIL PAN AND OIL PUMP5-63 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE OIL PAN 5-66. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE SPROCKET AND CHAIN 5-66. . . . . . . . . . . . . . . . . . . .
CHECKING THE OIL PUMP 5-67. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE RELIEF VALVE 5-67. . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE OIL DELIVERY PIPE AND OIL PIPE 5-68. . . . . . . . .
CHECKING THE OIL STRAINER 5-68. . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE OIL NOZZLES 5-68. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ASSEMBLING THE OIL PUMP 5-68. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE OIL / WATER PUMP ASSEMBLY 5-69. . . . . . . . . . . .
INSTALLING THE OIL PAN 5-71. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ProCarManuals.com
CRANKCASE5-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DISASSEMBLING THE CRANKCASE 5-74. . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CRANKCASE 5-75. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE BEARINGS AND OIL SEALS 5-75. . . . . . . . . . . . . . . .
ASSEMBLING THE CRANKCASE 5-75. . . . . . . . . . . . . . . . . . . . . . . . . . .
CONNECTING RODS AND PISTONS5-77 . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE CONNECTING RODS AND PISTONS 5-78. . . . . . . .
REMOVING THE CRANKSHAFT ASSEMBLY 5-79. . . . . . . . . . . . . . . . .
CHECKING THE CYLINDER AND PISTON 5-79. . . . . . . . . . . . . . . . . . .
CHECKING THE PISTON RINGS 5-80. . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE PISTON PINS 5-81. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE BIG END BEARINGS 5-82. . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE CONNECTING ROD AND PISTON 5-86. . . . . . . . . .
CRANKSHAFT5-92 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CRANKSHAFT 5-93. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CRANKSHAFT DRIVE SPROCKET 5-93. . . . . . . . . .
CHECKING THE CRANKSHAFT JOURNAL BEARINGS 5-93. . . . . . . .
INSTALLING THE CRANKSHAFT 5-96. . . . . . . . . . . . . . . . . . . . . . . . . . . .
TRANSMISSION5-97 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TRANSMISSION, SHIFT DRUM ASSEMBLY AND
SHIFT FORKS 5-97. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
REMOVING THE TRANSMISSION 5-103. . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE SHIFT FORKS 5-103. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE SHIFT DRUM ASSEMBLY 5-104. . . . . . . . . . . . . . . . . . .
CHECKING THE TRANSMISSION 5-104. . . . . . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE TRANSMISSION 5-105. . . . . . . . . . . . . . . . . . . . . . . . . .
CHAPTER 6
COOLING SYSTEM
RADIATOR6-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE RADIATOR 6-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE RADIATOR 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OIL COOLER6-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE OIL COOLER 6-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INSTALLING THE OIL COOLER 6-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
THERMOSTAT6-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE THERMOSTAT 6-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ASSEMBLING THE THERMOSTAT ASSEMBLY 6-11. . . . . . . . . . . . . . .
INSTALLING THE THERMOSTAT ASSEMBLY 6-11. . . . . . . . . . . . . . . .
WATER PUMP6-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IMPELLER SHAFT 6-12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DISASSEMBLING THE WATER PUMP 6-14. . . . . . . . . . . . . . . . . . . . . . .
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CHECKING THE WATER PUMP 6-14. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ASSEMBLING THE WATER PUMP 6-15. . . . . . . . . . . . . . . . . . . . . . . . . .
CHAPTER 7
FUEL INJECTION SYSTEM
FUEL INJECTION SYSTEM7-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WIRING DIAGRAM 7-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ECU’S SELF-DIAGNOSTIC FUNCTION 7-4. . . . . . . . . . . . . . . . . . . . . .
SUBSTITUTE CHARACTERISTICS OPERATION CONTROL
(FAIL-SAFE ACTION) 7-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FAIL-SAFE ACTIONS TABLE 7-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING CHART 7-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSTIC MODE 7-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING DETAILS 7-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
THROTTLE BODIES7-35 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INJECTORS 7-37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE INJECTORS 7-39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE THROTTLE BODIES 7-39. . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE THROTTLE BODY JOINTS 7-39. . . . . . . . . . . . . . . . . .
CHECKING THE PRESSURE REGULATOR 7-40. . . . . . . . . . . . . . . . . .
CHECKING THE FUEL PUMP AND PRESSURE REGULATOR
OPERATION 7-40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING AND ADJUSTING THE THROTTLE POSITION
SENSOR 7-41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING AND ADJUSTING THE SUB-THROTTLE POSITION
SENSOR 7-43. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING AND ADJUSTING THE THERMO WAX 7-45. . . . . . . . . . . .
AIR INDUCTION SYSTEM7-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AIR INJECTION 7-46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AIR CUT-OFF VALVE 7-46. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AIR INDUCTION SYSTEM DIAGRAMS 7-47. . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE AIR INDUCTION SYSTEM 7-48. . . . . . . . . . . . . . . . . .
CHAPTER 8
ELECTRICAL SYSTEM
ELECTRICAL COMPONENTS8-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING SWITCH CONTINUITY8-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE SWITCHES8-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE BULBS AND BULB SOCKETS8-5 . . . . . . . . . . . . . . . . .
TYPES OF BULBS 8-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHECKING THE CONDITION OF THE BULBS 8-5. . . . . . . . . . . . . . . .
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1-10
SPECIAL TOOLS
GEN
INFO
Tool No.Tool name / FunctionIllustration
90890-01441
YM-01441
Fork spring compressor
This tool is used to disassemble or
assemble the front fork legs.
90890-01442
YM-01442
Fork seal driver
This tool is used to install the front fork’s oil
seal and dust seal.
90890-03094
YU-08030
Vacuum gauge
This guide is used to synchronize the car-
buretors.
Compression
gauge
90890-03081
YU-33223
Adapter
90890-04136Compression gauge
Compression gauge adapter
These tools are used to measure engine
compression.
Valve spring compressor
90890-04019
YM-04019
Attachment
90890-04108
YM-01253
90890-04114
YM-4114Valve spring compressor
Valve spring compressor attachment
These tools are used to remove or install
the valve assemblies.
Middle driven shaft
bearing driver
90890-04058
YM-4058
Mechanical seal
installer
90890-04078
YM-33221Middle driven shaft bearing driver
Mechanical seal installer
These tools are used to install the water
pump seal.
90890-04086
YM-91042
Clutch holding tool
This tool is used to hold the clutch boss
when removing or installing the clutch boss
nut.
90890-04111
90890-04116
YM-4116
Valve guide remover
This tool is used to remove or install the
valve guides.
90890-04112
90890-04117
YM-4117
Valve guide installer
This tool is used to install the valve guides.
ProCarManuals.com
2-3
ENGINE SPECIFICATIONSSPEC
ItemStandardLimit
Oil filter
Oil filter type
Bypass valve opening pressure
Paper
80 120 kPa (0.8 1.2 kg / cm2,
0.8 1.2 bar, 11.6 17.4 psi)
Oil pump
Oil pump type
Inner-rotor-to-outer-rotor-tip
clearance
Outer-rotor-to-oil-pump-housing
clearance
Trochoid
0.01 0.10 mm
(0.0004 0.0039 in)
0.09 0.15 mm
(0.00035 0.0059 in)
0.18 mm
(0.0071 in)
0.22 mm
(0.0087 in)
Cooling system
Radiator capacity
Radiator cap opening pressure
Radiator core
Width
Height
Depth
Coolant reservoir
Capacity
Water pump
Water pump type
Reduction ratio
Max. impeller shaft tilt
2.51 L (2.21 Imp qt, 2.65 US qt)
108 137 kPa (1.08 1.37 kg / cm2,
1.0 1.3 bar, 15.6 19.9 psi)
380 mm (14.96 in)
258 mm (10.2 in)
24 mm (0.94 in)
0.25 L (0.22 Imp qt, 0.26 US qt)
Single suction centrifugal pump
65 / 43 25 / 32 (1.181)
0.15 mm
(0.006 in)
Starting system typeElectric starter
Spark plugs
Model (manufacturer) quantity
Spark plug gap
CR9EK (NGK) 4
0.6 0.7 mm (0.0236 0.0276 in)
Cylinder head
Volume
Max. warpage
12.5 13.1 cm3 (0.76 0.80 cu.in)
0.10 mm
(0.0039 in)
ProCarManuals.com
2-19
TIGHTENING TORQUESSPEC
Use a lock
washer
TIGHTENING TORQUES
ENGINE TIGHTENING TORQUES
ItemFastenerThreadQ’tyTightening torqueRemarksItemFastenersizeQtyNmmkgftlbRemarks
Spark plugs—M104131.39.4
Cylinder headNutM1010See NOTE 1
BoltM62121.28.7
Camshaft capsBoltM628101.07.2
Cylinder head coverBoltM66121.28.7
Cylinder head (exhaust pipe)Stud boltM88151.511
Air indication system capBoltM64101.07.2
Camshaft sprocketsBoltM74242.417
Cylinder head and throttle bodyClampM5430.32.2
Connecting rod capsBoltM8820+1502.0+15014+150
Generator rotorBoltM101606.043
Timing chain tensionerBoltM62101.07.2
Water pump outlet pipeBoltM61101.07.2
Water pump inlet pipeBoltM61101.07.2
(water pump side)
Water pump inlet pipe (front side)BoltM61101.07.2
Oil / water pump assembly
sprocketBoltM61151.511
Water pumpBoltM62121.28.7
Thermostat coverNutM62101.07.2
Thermostat inlet pipeBoltM61101.07.2
Oil coolerBoltM201636.346
Engine oil drain boltBoltM141434.331
Oil pipeBoltM62101.07.2
Oil strainerBoltM63101.07.2
Oil delivery pipeBoltM63101.07.2
Oil filter union boltBoltM201707.051
Oil filter—M201171.712
Oil panBoltM614121.28.7
Oil panBoltM61121.28.7
Air filter case coverScrewM5101.70.171.2
Throttle body and throttle body
jointClampM5430.32.2
Throttle body and funnelBoltM564.20.423.0
Throttle cableNutM614.50.453.3
Throttle cable adjusterBoltM614.50.453.3
Stator coilScrewM63141.410
Generator rotor cover and
bearing housingScrewM63101.07.2
Pull lever coverBoltM62101.07.2
Thermostat assembly stayBoltM62101.07.2
Starter clutch idler gearBoltM61101.07.2
Clutch bossNutM201959.569Stake
Clutch springBoltM66101.07.2
Drive sprocketNutM221858.561
ProCarManuals.com
2-25
LUBRICATION POINTS AND LUBRICANT TYPESSPEC
EAS00031
LUBRICATION POINTS AND LUBRICANT TYPES
ENGINE
Lubrication point
Lubricant
Oil seal lips
O-rings
Bearings
Crankshaft pins
Piston surfaces
Piston pins
Crankshaft journals
Camshaft lobes
Camshaft journals
Valve stems (intake and exhaust)
Valve stem ends (intake and exhaust)
Water pump impeller shaft
Oil pump rotors (inner and outer)
Oil pump housing
Oil strainer
Clutch (pull rod)
Oil / water pump drive sprocket and washer
Clutch (thrust plate)
Starter clutch idle gear inner surface
Starter clutch assembly
Primary driven gear
Transmission gears (wheel and pinion)
Main axle and drive axle
Shift drum
Shift forks and shift fork guide bars
Shift shaft
Shift shaft boss
Cylinder head cover mating surfaceYamaha bond
No.1215
Crankcase mating surfaceYamaha bond
No.1215
Clutch cover (crankcase mating surface)Yamaha bond
No.1215
Generator rotor cover (crankcase mating surface)Yamaha bond
No.1215
Pickup rotor coverYamaha bond
No.1215
ProCarManuals.com
2-27
1Radiator fan
2Radiator
3Water pump
COOLING SYSTEM DIAGRAMSSPEC
EAS00033
COOLING SYSTEM DIAGRAMS
ProCarManuals.com