Page 22 of 646

CHAPTER 4
ENGINE
SEAT, FUEL TANK
AND SIDE COVERS ..................................4-1
EXHAUST PIPE AND SILENCER .............4-3
RADIATOR ................................................4-5
CARBURETOR ..........................................4-8
CAMSHAFTS ...........................................4-21
CYLINDER HEAD ....................................4-29
VALVES AND VALVE SPRINGS ............4-33
CYLINDER AND PISTON ........................4-42
CLUTCH ...................................................4-48
OIL FILTER, WATER PUMP
AND CRANKCASE COVER (RIGHT) .....4-55
BALANCER .............................................4-62
OIL PUMP ................................................4-65
KICK AXLE AND SHIFT SHAFT .............4-69
CDI MAGNETO ........................................4-76
ENGINE REMOVAL .................................4-80
CRANKCASE AND CRANKSHAFT ........4-85
TRANSMISSION, SHIFT CAM
AND SHIFT FORK ...................................4-94
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL .......5-1
FRONT BRAKE AND REAR BRAKE .....5-10
FRONT FORK ..........................................5-26
HANDLEBAR ...........................................5-42
STEERING ...............................................5-48
SWINGARM .............................................5-53
REAR SHOCK ABSORBER ....................5-61
Page 74 of 646

SPEC
2 - 3 Transmission:
Primary reduction system Gear
Primary reduction ratio 61/23 (2.652)
Secondary reduction system Chain drive
Secondary reduction ratio 51/14 (3.643)
Transmission type Constant mesh, 4-speed
Operation Left foot operation
Gear ratio: 1st 27/14 (1.929)
2nd 25/16 (1.563)
3rd 23/18 (1.278)
4th 21/20 (1.050)
Chassis:
Frame type Semi double cradle
Caster angle 27.1°
Trail 116 mm (4.57 in) (For USA, ZA, AUS, NZ)
117 mm (4.61 in) (For EUROPE except F)
118 mm (4.65 in) (For F, CDN)
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN, ZA, AUS, NZ
and F)
80/100-21 51R (For EUROPE except F)
Size (rear) 110/90-19 62M (For USA, CDN, ZA, AUS, NZ
and F)
110/90-19 NHS (For EUROPE except F)
Tire pressure (front and rear) 100 kPa (1.0 kgf/cm
2, 15 psi)
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 315 mm (12.4 in)
Electrical:
Ignition system CDI magneto
GENERAL SPECIFICATIONS
Page 81 of 646
SPEC
2 - 10 Item Standard
Lubrication chart:
Pressure feed
Splashed scavenge
Oil strainer
Oil pan Oil pump rotor 2
Oil pump rotor 1
Oil tank
Oil filter
Check ball
Cylinder head
Crank pinPiston pinPiston
Drive axleMain axleTransmission gears
Camshaft
Valve lifter
MAINTENANCE SPECIFICATIONS
Page 103 of 646

2 - 14
SPECCARACTERISTIQUES D’ENTRETIEN
Roue:
Type de roue avant Roue à rayons ----
Type de roue arrière Roue à rayons ----
Taille/matériau de la jante avant 21 × 1,60/Aluminium ----
Taille/matériau de la jante arrière 19 × 2,15/Aluminium ----
Limite de voilage de la jante:
Radial ---- 2,0 mm (0,08 in)
Latéral ---- 2,0 mm (0,08 in)
Chaîne de transmission:
Type/fabricant DID520DMA2 SDH/DAIDO ----
Nombre de maillons 115 maillons + attache ----
Jeu de la chaîne 48 à 58 mm (1,9 à 2,3 in) ----
Longueur de la chaîne (15 maillons) ---- 242,9 mm
(9,563 in)
Frein à disque avant:
Diamètre extérieur du disque × Epais-
seur250 × 3,0 mm (9,84 × 0,12 in) 250 × 2,5 mm
(9,84 × 0,10 in)
Epaisseur de plaquette 4,4 mm (0,17 in) 1,0 mm (0,04 in)
Diamètre intérieur du maître cylindre 11,0 mm (0,433 in) ----
Diamètre intérieur du cylindre d’étrier 27,0 mm (1,063 in) × 2 ----
Type de liquide de frein DOT n°4 ----
Frein à disque arrière:
Diamètre extérieur du disque × Epais-
seur245 × 4,0 mm (9,65 × 0,16 in) 245 × 3,5 mm
(9,65 × 0,14 in)
Limite de déflexion ---- 0,15 mm (0,006 in)
Epaisseur de plaquette 6,4 mm (0,25 in) 1,0 mm (0,04 in)
Diamètre intérieur du maître cylindre 11,0 mm (0,433 in) ----
Diamètre intérieur du cylindre d’étrier 25,4 mm (1,000 in) × 1 ----
Type de liquide de frein DOT n°4 ----
Levier et pédale de frein:
Position du levier de frein 95 mm (3,74 in) ----
Hauteur de la pédale de frein
(distance verticale au-dessus du som-
met du repose-pied)5 mm (0,20 in) ----
Garde du levier d’embrayage (à l’extré-
mité du levier)8 à 13 mm (0,31 à 0,51 in) ----
Jeu de la poignée des gaz 3 à 5 mm (0,12 à 0,20 in) ---- Elément Standard Limite
Page 142 of 646

3 - 1
INSP
ADJ
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the
required maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in
maintaining and lubricating your machine, consult your Yamaha dealer.
ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks
ENGINE OIL
Replace
VALVES
The engine must be cold.
Check the valve seats
and valve stems for wear. Check the valve clearances
Inspect
Replace
VALVE SPRINGS
Check the free length and
the tilt. Inspect
Replace
VALVE LIFTERS
Check for scratches and
wear. Inspect
Replace
CAMSHAFTS Inspect the camshaft sur-
face.
Inspect the decompres-
sion system Inspect
Replace
CAMSHAFT SPROCKETS
Check for wear on the
teeth and for damage. Inspect
Replace
PISTON
Inspect crack
Inspect carbon deposits
and eliminate them. Inspect
Clean
Replace
PISTON RING
Check ring end gap Inspect
Replace
PISTON PIN
Inspect
Replace
CYLINDER HEAD Inspect carbon deposits
and eliminate them.
Change gasket Inspect and clean
CYLINDER
Inspect and clean
Inspect score marks
Inspect wear
Replace
CLUTCH
Inspect housing, friction
plate, clutch plate and
spring Inspect and adjust
Replace
TRANSMISSION
Inspect
Replace bearing
Page 354 of 646
4 - 57
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
REMOVAL POINTS
EC4G3110
Impeller shaft
1. Remove:
Impeller 1
Plain washer 2
Impeller shaft 3
NOTE:
Hold the impeller shaft on its width across the
flats a with spanners, etc. and remove the
impeller.
EC4G3210
Oil seal
NOTE:
It is not necessary to disassemble the water
pump, unless there is an abnormality such as
excessive change in coolant level, discolora-
tion of coolant, or milky transmission oil.
1. Remove:
Bearing 1
Oil seal 2
INSPECTION
EC444200
Impeller shaft
1. Inspect:
Impeller shaft 1
Bend/wear/damage → Replace.
Fur deposits → Clean.
Page 414 of 646
4 - 87
ENGCRANKCASE AND CRANKSHAFT
CRANKCASE BEARING
Extent of removal:
1 Crankcase bearing removal
Extent of removal Order Part name Q’ty Remarks
CRANKCASE BEARING
REMOVAL
Preparation for removal Transmission Refer to “TRANSMISSION, SHIFT
CAM AND SHIFT FORK” section.
Shift cam and shift fork
1 Oil seal 3
2 Bearing 10 Refer to “REMOVAL POINTS”.
1
Page 424 of 646
4 - 92
ENGCRANKCASE AND CRANKSHAFT
NOTE:
Hold the connecting rod at top dead center
with one hand while turning the nut of the
installing tool with the other. Operate the
installing tool until the crankshaft bottoms
against the bearing.
Before installing the crankshaft, clean the
contacting surface of crankcase.
CAUTION:
Do not use a hammer to drive in the crank-
shaft.
2. Check:
Shifter operation
Transmission operation
Unsmooth operation → Repair.
3. Install:
Oil strainer 1
Bolt (oil strainer) 2
4. Apply:
Sealant
On the crankcase (right) 1.
NOTE:
Clean the contacting surface of crankcase (left
and right) before applying the sealant.
Quick gasket®:
ACC-QUICK-GS-KT
YAMAHA Bond No. 1215:
90890-85505
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)