CHAPTER 4
ENGINE
SEAT, FUEL TANK AND SIDE
COVERS..................................... 4-1
EXHAUST PIPE AND
SILENCER.................................. 4-7
RADIATOR............................... 4-13
CARBURETOR........................ 4-21
CAMSHAFTS........................... 4-51
CYLINDER HEAD.................... 4-73
VALVES AND VALVE
SPRINGS.................................. 4-81
CYLINDER AND PISTON...... 4-101
CLUTCH................................. 4-117
OIL FILTER ELEMENT,
WATER PUMP AND RIGHT
CRANKCASE COVER........... 4-135
BALANCER............................ 4-151
OIL PUMP.............................. 4-159
KICK SHAFT AND
SHIFT SHAFT........................ 4-169
AC MAGNETO AND STARTER
CLUTCH................................. 4-185
ENGINE REMOVAL............... 4-207
CRANKCASE AND
CRANKSHAFT....................... 4-221
TRANSMISSION, SHIFT CAM
AND SHIFT FORK................. 4-245
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR
WHEEL....................................... 5-1
FRONT BRAKE AND
REAR BRAKE.......................... 5-23
FRONT FORK.......................... 5-61
HANDLEBAR........................... 5-91
STEERING............................. 5-103
SWINGARM........................... 5-119
REAR SHOCK ABSORBER.. 5-139
CHAPITRE 4
MOTEUR
SELLE, RESERVOIR DE
CARBURANT ET CACHES
LATERAUX..................................... 4-2
TUYAU D’ECHAPPEMENT ET
SILENCIEUX................................... 4-8
RADIATEUR................................. 4-14
CARBURATEUR.......................... 4-22
ARBRES A CAMES...................... 4-52
CULASSE....................................... 4-74
SOUPAPES ET RESSORTS DE
SOUPAPE....................................... 4-82
CYLINDRE ET PISTON............ 4-102
EMBRAYAGE............................. 4-118
ELEMENT DE FILTRE A
HUILE, POMPE A EAU ET
DEMI-CARTER DROIT............ 4-136
BALANCIER............................... 4-152
POMPE A HUILE....................... 4-160
ARBRE DE KICK ET
ARBRE DE SELECTEUR.......... 4-170
MAGNETO CA ET
ROCHET DE DEMARRAGE ... 4-186
DEPOSE DU MOTEUR.............. 4-208
CARTER ET VILEBREQUIN... 4-222
BOITE A VITESSES,
TAMBOUR ET FOURCHETTES
DE SELECTION.......................... 4-246
CHAPITRE 5
PARTIE CYCLE
ROUE AVANT ET ROUE
ARRIERE......................................... 5-2
FREIN AVANT ET FREIN
ARRIERE....................................... 5-24
FOURCHE AVANT...................... 5-62
GUIDON......................................... 5-92
DIRECTION................................ 5-104
BRAS OSCILLANT.................... 5-120
AMORTISSEUR ARRIERE...... 5-140
1 - 45
GEN
INFO
TORQUE-CHECK POINTS
Frame construction Frame to rear frame
Combined seat and fuel tank Fuel tank to frame
Exhaust system Silencer to rear frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering Steering stem to handlebar Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension Front Steering stem to front fork Front fork to upper bracket
Front fork to lower bracket
Rear For link type Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Rear Installation of rear
shock absorberRear shock absorber to frame
Rear Installation of swingarm Tightening of pivot shaft
Wheel Installation of wheel Front Tightening of wheel axle
Tightening of axle holder
Rear Tightening of wheel axle
Wheel to rear wheel sprocket
Brake Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Rear Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Fuel system Fuel tank to fuel cock
Lubrication system Tightening of oil hose clamp
NOTE:Concerning the tightening torque, refer to
“MAINTENANCE SPECIFICATIONS” sec-
tion in the CHAPTER 2.
TORQUE-CHECK POINTS
MAINTENANCE SPECIFICATIONS
2 - 14
SPEC
NOTE:
1. First, tighten the steering nut approximately 38 Nm (3.8 m kg, 27 ft lb) by using the steering
nut wrench, then loosen the steering nut one turn.
2. Retighten the steering nut 7 Nm (0.7 m kg, 5.1 ft lb). Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Upper bracket and outer tube M8 × 1.25 4 23 2.3 17
Lower bracket and outer tube M8 × 1.25 4 20 2.0 14
Upper bracket and steering stem M24 × 1.0 1 145 14.5 105
Handlebar upper holder and upper bracket M8 × 1.25 4 28 2.8 20
Steering stem and steering ring nut M28 × 1.0 1 Refer to NOTE.
Front fork and front fork cap bolt M48 × 1.0 2 30 3.0 22
Front fork and base valve M30 × 1.0 2 55 5.5 40
Front fork cap bolt and damper rod M12 × 1.25 2 29 2.9 21
Front fork bleed screw and front fork cap bolt M5 × 0.8 2 1 0.1 0.7
Front fork and front fork protector M6 × 1.0 6 10 1.0 7.2
Front fork and brake hose holder M6 × 1.0 2 10 1.0 7.2
Front fork and brake hose cover (M8) M8 × 1.25 1 16 1.6 11
(M6) M6 × 1.0 1 7 0.7 5.1
Throttle grip cap M5 × 0.8 2 4 0.4 2.9
Front brake master cylinder M6 × 1.0 2 9 0.9 6.5
Brake lever mounting bolt M6 × 1.0 1 6 0.6 4.3
Brake lever mounting nut M6 × 1.0 1 6 0.6 4.3
Brake lever position locknut M6 × 1.0 1 5 0.5 3.6
Front brake hose guide M5 × 0.8 2 4 0.4 2.9
Clutch lever holder M5 × 0.8 2 4 0.4 2.9
Clutch lever mounting nut M6 × 1.0 1 4 0.4 2.9
Hot starter lever holder M5 × 0.8 2 4 0.4 2.9
Hot starter lever mounting nut M5 × 0.8 1 2 0.2 1.4
Front brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
Front brake hose union bolt M10 × 1.25 2 30 3.0 22
Front brake caliper M8 × 1.25 2 23 2.3 17
Pad pin plug M10 × 1.0 2 3 0.3 2.2
Front brake caliper and pad pin M10 × 1.0 1 18 1.8 13
Rear brake caliper and pad pin M10 × 1.0 1 18 1.8 13
Brake caliper and bleed screw M8 × 1.25 2 6 0.6 4.3
Front wheel axle and axle nut M16 × 1.5 1 105 10.5 75
Front wheel axle holder M8 × 1.25 4 23 2.3 17
Front brake disc M6 × 1.0 6 12 1.2 8.7
Rear brake disc M6 × 1.0 6 14 1.4 10
Brake pedal M8 × 1.25 1 26 2.6 19
Rear brake master cylinder M6 × 1.0 2 11 1.1 8.0
Rear brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
Rear brake hose union bolt M10 × 1.25 2 30 3.0 22
Rear wheel axle and axle nut M20 × 1.5 1 125 12.5 90
3 - 3
INSP
ADJ
MAINTENANCE INTERVALS
*marked: For USAFRONT FORKS
Inspect and adjust
Replace oilSuspension oil “01”
Replace oil seal
FRONT FORK OIL SEAL AND DUST SEAL
Clean and lubeLithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube
(After
rain
ride)Molybdenum disulfide
grease
Retighten
DRIVE CHAIN GUIDE AND ROLLERS
Inspect
DRIVE CHAIN STOPPER
Inspect
SWINGARMMolybdenum disulfide
grease
Inspect, lube and retighten
RELAY ARM, CONNECTING ROD Molybdenum disulfide
grease
Inspect, lube and retighten
SIDESTAND
LubricateLithium base grease
STEERING HEAD
Inspect free play and retighten
Clean and lubeLithium base grease
Replace bearing
TIRE, WHEELS
Inspect air pressure, wheel run-out, tire
wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
LubricateLithium base grease
THROTTLE, CONTROL CABLE Yamaha cable lube or SAE
10W-30 motor oil
Inspect dirt and wear on the
throttle cable on the
carburetor side. Check routing and connection
Lubricate
Inspect and clean (throttle cable)
HOT STARTER, CLUTCH LEVER
Inspect free play
BATTERY
Check terminal for looseness and
corrosionItemAfter
break-inEvery
race
Every third
(or
500 km)Every fifth
(or
1,000 km)As
requiredRemarks
3 - 16
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.P.3-21 ~ 29
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-35
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-39 ~ 47
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-29 ~ 31
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-31 ~ 33
Brakes Check the play of front brake and effect of front and rear brake. P.3-65 ~ 77
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-79 ~ 83
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-99 ~ 101
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-101 ~ 103
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-85 ~ 97
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or when
the front forks travel up and down.—
Exhaust pipeCheck that the exhaust pipe is tightly mounted and has no
cracks.P.4-7 ~ 11
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-77
Lubrication Check for smooth operation. Lubricate if necessary. P.3-105
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-45
Lead connectorsCheck that the AC magneto, CDI unit, and ignition coil are
connected tightly.P.1-9
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 42
3 - 101
INSP
ADJ
2. Inspect:
Bearing free play
Exist play
→ Replace.
EC36U013STEERING HEAD INSPECTION
AND ADJUSTMENT
1. Elevate the front wheel by plac-
ing a suitable stand under the
engine.
2. Check:
Steering stem
Grasp the bottom of the forks
and gently rock the fork
assembly back and forth.
Free play
→ Adjust steering
head.
3. Check:
Steering smooth action
Turn the handlebar lock to
lock.
Unsmooth action
→ Adjust
steering ring nut.
4. Adjust:
Steering ring nut
Steering ring nut adjustment
steps:
Remove the headlight.
Remove the handlebar and
handlebar upper bracket.
Loosen the steering ring nut
1
using the steering nut wrench
2.
Steering nut wrench:
YU-33975/90890-01403
Tighten the steering ring nut
3
using steering nut wrench
4.
NOTE:Set the torque wrench to the
steering nut wrench so that they
form a right angle.
Steering nut wrench:
YU-33975/90890-01403
T R..
Steering ring nut
(initial tightening):
38 Nm
(3.8 m kg, 27 ft lb)
2. Contrôler:
Jeu de roulement
Il y a du jeu → Remplacer.
CONTROLE ET REGLAGE DE LA
TETE DE FOURCHE
1. Soulever la roue avant en mettant
un support convenable sous le
moteur.
2. Contrôler:
Arbre de direction
Saisir la fourche par le bas et bas-
culer l’ensemble en avant et en
arrière.
Jeu → Régler la tête de fourche.
3. Contrôler:
Action régulière de la direction
Tourner le guidon à fond dans les
deux sens.
Action irrégulière → Régler
l’écrou annulaire de direction.
4. Régler:
Ecrou crénelé de direction
Etapes de réglage de l’écrou cré-
nelé de direction:
Retirer le phare.
Retirer le guidon et le support
supérieur.
Desserrer l’écrou crénelé de direc-
tion 1 en utilisant la clé à ergots
2.
Clé à ergots:
YU-33975/90890-01403
Serrer l’écrou crénelé de direction
3 en utilisant la clé 4.
N.B.:
Régler la clef dynamométrique à la
clé à ergots pour former un angle
droit.
Clé à ergots:
YU-33975/90890-01403
T R..
Ecrou crénelé de direction
(serrage initial):
38 Nm
(3,8 m kg, 27 ft lb)
CHASSIS
PARTIE CYCLE