2002 YAMAHA WR 426F oil

3 - 22
INSP
ADJ
VALVE CLEARANCE ADJUSTMENT
Round off the last digit of the installed pad
number to the nearest increment.
Last digit of pad
numberRounded value
0, 1 or 2 0
4, 5 or 6 5
8 or 9 10
EXAMPLE:
Installed pad number = 148
Rounded off value = 150
NOTE:
Pads can only be selected in 0.05 mm incre-
ments.
Locate the rounded-off value and the mea-
sured valve clearance in the chart “PAD
SELECTION TABLE”. The field where
these two coordinates intersect shows the
new pad number to use.
NOTE:
Use the new pad number only as a guide
when verifying the valve clearance adjust-
ment.
Install the new pads 0 and the valve lift-
ers A.
NOTE:
Apply the engine oil on the valve lifters.
Apply the molybdenum disulfide oil on the
valve stem ends.
Valve lifter must turn smoothly when
rotated with a finger.
Be careful to reinstall valve lifters and
pads in their original place.
Install the decompression shaft B, plain
washer C, bolt D, guide E, bolt F and
decompression cable G.
NOTE:
Apply the engine oil on the decompression
shaft.
T R..
Bolt (decompression shaft):
7 Nm (0.7 m • kg, 5.1 ft • lb)
Bolt (guide):
10 Nm (1.0 m • kg, 7.2 ft • lb)

3 - 34
INSP
ADJ
DRIVE CHAIN INSPECTION
5. Check:
Drive chain stiffness a
Clean and oil the chain and hold as
illustrated.
Stiff → Replace the drive chain.
6. Install:
Joint 1
O-ring 2
Drive chain 3
NOTE:
When installing the drive chain, apply the lith-
ium soap base grease on the joint and O-rings.
7. Install:
Link plate 4
NOTE:
Press the link plate onto the joint using a
chain riveter 5.
Rivet the end of the joint using a chain riveter
6.
After rivetting the joint, make sure its move-
ment is smooth.
New
New
8. Lubricate:
Drive chain
Drive chain lubricant:
SAE 10W-30 motor oil or suit-
able chain lubricants

3 - 36
INSP
ADJFRONT FORK INSPECTION/
FRONT FORK OIL SEAL AND DUST SEAL CLEANING
Tighten the axle nut while pushing down
the drive chain.
T R..
Axle nut:
125 Nm (12.5 m • kg, 90 ft • lb)
Tighten the locknuts.
EC36C000
FRONT FORK INSPECTION
1. Inspect:
Front fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage → Repair
or replace.
EC36D001
FRONT FORK OIL SEAL AND DUST SEAL
CLEANING
1. Remove:
Protector
Dust seal 1
NOTE:
Use a thin screw driver, and be careful not to
damage the inner fork tube and dust seal.
2. Clean:
Dust seal a
Oil seal b
NOTE:
Clean the dust seal and oil seal after every
run.
Apply the lithium soap base grease on the
inner tube.

3 - 39
INSP
ADJ
REAR SHOCK ABSORBER INSPECTION
STANDARD POSITION:
This is the position which is back by the spe-
cific number of clicks from the fully turned-in
position.
CAUTION:
Do not force the adjuster past the minimum
or maximum extent of adjustment. The
adjuster may be damaged.
WARNING
Always adjust each front fork to the same
setting. Uneven adjustment can cause poor
handling and loss of stability.
3. Install:
Rubber cap
T R..
Standard position:
12 clicks out
EC36K000
REAR SHOCK ABSORBER INSPECTION
1. Inspect:
Swingarm smooth action
Abnormal noise/unsmooth action →
Grease the pivoting points or repair the
pivoting points.
Damage/oil leakage → Replace.

INSP
ADJ
CONTROLE DE PRESSION DES PNEUS/CONTROLE ET SERRAGE DES RAYONS/
CONTROLE DE LA ROUE
REIFENLUFTDRUCK KONTROLLIEREN/SPEICHEN KONTROLLIEREN UND
FESTZIEHEN/RÄDER KONTROLLIEREN
COMPROBACIÓN DE LA PRESIÓN DE LOS NEUMÁTICOS/INSPECCIÓN Y AJUSTE DE
LOS RADIOS/INSPECCIÓN DE RUEDAS
REIFENLUFTDRUCK KONTROL-
LIEREN
1. Messen:
Reifenluftdruck
Unvorschriftsmäßig → Ein-
stellen.
HINWEIS:
Den Reifenluftdruck bei kalten Rei-
fen kontrollieren.
Bei zu niedrigem Reifendruck liegt
die Reifenwulst nicht fest an, was
dazu führen kann, daß sich der
Reifen von der Felge löst.
Ein geneigter Reifenventilschaft
deutet an, daß der Reifen ver-
rutscht ist.
Bei geneigtem Reifenventilschaft
muß die Reifenposition berichtigt
werden.
Standard-Reifenluft-
druck
100 kPa (1,0 bar)
SPEICHEN KONTROLLIEREN
UND FESTZIEHEN
1. Kontrollieren:
Speichen 1
Verzug/Beschädigung →
Erneuern.
Speichen locker → Nach-
spannen.
2. Festziehen:
Speichen
HINWEIS:
Die Speichen müssen vor und nach
dem Einfahren nachgezogen wer-
den. Nach jeder Übungsfahrt bzw.
Rennen die Speichenspannung prü-
fen.
T R..3 Nm (0,3 m · kg)
RÄDER KONTROLLIEREN
1. Messen:
Felgenschlag
Das Rad anheben und dre-
hen.
Übermäßig → Erneuern. CONTROLE DE PRESSION DES
PNEUS
1. Mesurer:
Pression des pneus
Hors spécification → Régler.
N.B.:
Vérifier le pneu alors qu’il est froid.
Des butées de bourrelet lâches permet-
tent au pneu de se détacher de sa posi-
tion sur la jante lorsque la pression des
pneus est basse.
Une tige de soupape de pneu inclinée
indique que le pneu se détache de sa
position sur la jante.
Si la tige de soupape de pneu est incli-
née, le pneu a tendance à se détacher
de sa position. Corriger la position du
pneu.
Pression des pneus stan-
dard:
100 kPa
(1,0 kgf/cm
2, 15 psi)
CONTROLE ET SERRAGE DES
RAYONS
1. Contrôler:
Rayons 1
Déformation/endommagement
→ Changer.
Rayons desserrés → Resserrer.
2. Serrer:
Rayon
N.B.:
Ne pas oublier de retendre les rayons
avant et après le rodage. Après un entraî-
nement ou une course, contrôler si les
rayons ne sont pas détendus.
T R..3 Nm (0,3 m · kg, 2,2 ft · lb)
CONTROLE DE LA ROUE
1. Mesure:
Voile de roue
Soulever la roue et la tourner.
Voile excessif → Changer.
3 - 44
COMPROBACIÓN DE LA PRE-
SIÓN DE LOS NEUMÁTICOS
1. Medir:
Presión de aire de los neumáticos
Fuera de especificaciones →
Ajustar.
NOTA:
Compruebe el neumático cuando esté frío.
Afloje los topes reforzados permitiendo
que se pueda retirar el neumático de su
posición en la llanta cuando la presión
de aire de los neumáticos sea baja.
Un vástago de la válvula del neumá-
tico inclinado indica que el neumático
se sale de su posición en la llanta.
Si detecta que el vástago de la válvula
del neumático está inclinado, debe
considerar que el neumático se ha
salido de su posición en la llanta.
Corrija su posición.
Presión de aire de los neu-
máticos estándar:
100 kPa
(1,0 kgf/cm
2, 15 psi)
INSPECCIÓN Y AJUSTE DE LOS
RADIOS
1. Inspeccionar:
Radios 1
Deformaciones/daños →
Reemplazar.
Radios holgados → Ajustar
nuevamente.
2. Apretar:
Radios
NOTA:
Asegúrese de ajustar nuevamente los
radios antes y después del rodaje. Des-
pués de realizar una práctica o empren-
der una carrera, compruebe la holgura de
los radios.
T R..3 Nm (0,3 m · kg, 2,2 ft · lb)
INSPECCIÓN DE RUEDAS
1. Inspeccionar:
Descentramiento de la rueda
Eleve la rueda y gírela.
Descentramiento anormal →
Reemplazar.

3 - 47
INSP
ADJ
LUBRICATION
LUBRICATION
To ensure smooth operation of all compo-
nents, lubricate your machine during setup,
after break-in, and after every race.
1All control cable
2Clutch lever pivot
3Shift pedal pivot
4Footrest pivot
5Throttle-to-handlebar contact
6Drive chain
7Tube guide cable winding portion
8Throttle cable end
9Clutch cable end
0Decompression cable endÅUse Yamaha cable lube or equivalent on these
areas.
ıUse SAE10W-30 motor oil or suitable chain
lubricants.
ÇLubricate the following areas with high quality,
lightweight lithium-soap base grease.
CAUTION:
Wipe off any excess grease, and avoid get-
ting grease on the brake discs.
AAA
AAB
CC

3 - 50
INSP
ADJ
REPLACING THE HEADLIGHT BULBS
REPLACING THE HEADLIGHT BULBS
1. Remove:
Headlight
Refer to “SEAT, FUEL TANK AND
SIDE COVERS” section in the CHAP-
TER 4.
2. Remove:
Headlight bulb holder cover 1
3. Detach:
Headlight bulb holder 1
4. Remove:
Headlight bulb 2
WARNING
Since the headlight bulb gets extremely
hot, keep flammable products and your
hands away from the bulb unit it has cooled
down.
5. Install:
Headlight bulb
Secure the new headlight bulb with the
headlight bulb holder.
CAUTION:
Avoid touching the glass part of the head-
light bulb to keep it free form 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.
6. Attach:
Headlight bulb holder
7. Install:
Headlight bulb holder cover
8. Install:
Headlight
Refer to “SEAT, FUEL TANK AND
SIDE COVERS” section in the CHAP-
TER 4.
New
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)

ENG
4 - 22
CAMSHAFTS
CAMSHAFTS
CYLINDER HEAD COVER
Extent of removal:1 Cylinder head cover removal
Extent of removal Order Part name Q’ty Remarks
CYLINDER HEAD COVER
REMOVAL
Preparation for removal Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Carburetor Refer to “CARBURETOR” section.
1 Spark plug 1
2 Engine upper bracket (right) 1
3 Engine upper bracket (left) 1
4 Cylinder head breather hose 1
5 Oil tank breather hose 1
6 Bolt (cylinder head cover) 2
7 Cylinder head cover 1
8 Gasket 1
9 Timing chain guide (upper) 1
1