torque YAMAHA YZ250F 2003 User Guide

4 - 28
ENG
With the rod fully wound and the chain
tensioner UP mark a facing upward,
install the gasket 1 and the timing chain
tensioner 2, and tighten the bolt 3 to the
specified torque.
T R..
Bolt (timing chain tensioner):
10 Nm (1.0 m • kg, 7.2 ft • lb)
Release the screwdriver, check the ten-
sioner rod to come out and tighten the
gasket 4 and the cap bolt 5 to the speci-
fied torque.
T R..
Tensioner cap bolt:
7 Nm (0.7 m • kg, 5.1 ft • lb)
5
4New
3. Turn:
Crankshaft
Counterclockwise several turns.
4. Check:
Rotor T.D.C. mark
Align with the crankcase align mark.
Camshaft match marks
Align with the cylinder head surface.
Out of alignment → Adjust.
5. Install:
Timing mark accessing screw 1
Crankshaft end accessing screw 2
CAMSHAFTS

ENG
4 - 86
DEPOSE DU MOTEUR
MOTOR DEMONTIEREN
RIMOZIONE DEL MOTORE
2. Montieren:
Sicherungsscheibe 1
Mutter (Antriebsritzel) 2
HINWEIS:
Beim Festziehen der Mutter die Hin-
terradbremse betätigen.
T R..75 Nm (7,5 m · kg)
3. Die Lasche der Sicherungs-
scheibe umbiegen, um die
Mutter zu sichern.
4. Montieren:
Antriebskettenritzel 1
Kettenschutz 2
Schraube (Kettenschutz) 3
T R..8 Nm (0,8 m · kg)
Ölschlauch und Leerlaufschalter
1. Montieren:
O-Ring 1
Paßstift 2
Ölschlauch 3
Schraube (Ölschlauch) 4
HINWEIS:
Lithiumfett auf den O-Ring auftragen.
2. Montieren:
Feder 1
Stift 2
O-Ring 3
Leerlaufschalter 4
Schraube (Leerlaufschalter)
5
HINWEIS:
Lithiumfett auf den O-Ring auftragen.
T R..10 Nm (1,0 m · kg)
T R..4 Nm (0,4 m · kg)
2. Monter:
Rondelle-frein 1
Ecrou (pignon d’entraînement)
2
N.B.:
Serrer l’écrou en actionnant le frein
arrière.
T R..75 Nm (7,5 m · kg, 54 ft · lb)
3. Courber la languette de la ron-
delle-frein pour verrouiller
l’écrou.
4. Monter:
Guide de pignon de chaîne de
transmission 1
Couvercle de chaîne 2
Vis (couvercle de chaîne) 3
T R..8 Nm (0,8 m · kg, 5,8 ft · lb)
Durit d’huile et contacteur de point
mort
1. Monter:
Joint torique 1
Goujon 2
Durit d’huile 3
Boulon (durit d’huile) 4
N.B.:
Enduire le joint torique de graisse à base
de savon au lithium.
2. Monter:
Ressort 1
Goupille 2
Joint torque 3
Contacteur de point mort 4
Vis (contacteur de point mort)
5
N.B.:
Enduire le joint torique de graisse à base
de savon au lithium.
T R..10 Nm (1,0 m · kg, 7,2 ft · lb)
T R..4 Nm (0,4 m · kg, 2,9 ft · lb)
2. Installare:
Rondella di bloccaggio 1
Dado (corona dentata trasmis-
sione) 2
NOTA:
Avvitare il dado agendo sul freno poste-
riore.
T R..75 Nm (7,5 m · kg, 54 ft · lb)
3. Piegare la linguetta della rondella
di bloccaggio.
4. Installare:
Guida corona catena di trasmis-
sione 1
Carterino corona catena di tra-
smissione 2
Vite (carterino corona catena di
trasmissione) 3
T R..8 Nm (0,8 m · kg, 5,8 ft · lb)
Flessibile dell’olio e interruttore di
folle
1. Installare:
O-ring 1
Grano di centraggio 2
Flessibile dell’olio 3
Bullone (tubo flessibile
dell’olio) 4
NOTA:
Applicare grasso a base di sapone di litio
sull’O-ring.
2. Installare:
Molla 1
Perno 2
O-ring 3
Interruttore folle 4
Vite (interruttore folle) 5
NOTA:
Applicare grasso a base di sapone di litio
sull’O-ring.
T R..10 Nm (1,0 m · kg, 7,2 ft · lb)
T R..4 Nm (0,4 m · kg, 2,9 ft · lb)

5 - 37
CHASFRONT FORK
26. Tighten:
Front fork cap bolt (locknut) 1
NOTE:
While compressing the fork spring, set the
thin type spanners 2 between the spacer 3
and spring guide 4.
Hold the locknut 5 and tighten the front fork
cap bolt with specified torque.
27. Install:
Front fork cap bolt 1
To outer tube.
NOTE:
Temporarily tighten the cap bolt.
T R..29 Nm (2.9 m · kg, 21 ft · lb)
28. Install:
Protector guide 1
Installation
1. Install:
Front fork 1
NOTE:
Temporarily tighten the pinch bolts (lower
bracket).
Do not tighten the pinch bolts (upper bracket)
yet.
2. Tighten:
Front fork cap bolt 1
3. Adjust:
Front fork top end a
Front fork top end (standard) a:
5 mm (0.20 in)
T R..30 Nm (3.0 m · kg, 22 ft · lb)

5 - 38
CHASFRONT FORK
4. Tighten:
Pinch bolt (upper bracket) 1
Pinch bolt (lower bracket) 2
ACHTUNG:CAUTION:
Tighten the lower bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.
5. Install:
Brake hose holder 1
Brake caliper 2
Bolt (brake caliper) 3
NOTE:
Fit the brake hose holder cut a over the pro-
jection b on the front fork and clamp the brake
hose.
6. Install:
Brake hose holder 1
Bolt (brake hose holder) 2
Protector 3
Bolt (protector) 4
NOTE:
When installing the brake hose holder, align
the top a of the brake hose neck with the
brake hose holder bottom b. Then pass the
brake hose 5 in front of the axle boss c and
fit it into the hose groove d so that the brake
hose does not contact the nut (wheel axle).
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
7. Adjust:
Rebound damping force
NOTE:
Turn in the damping adjuster 1 finger-tight
and then turn out to the originally set position.

5 - 49
CHAS
10. Tighten:
Pinch bolt (upper bracket) 1
Pinch bolt (lower bracket) 2
ACHTUNG:CAUTION:
Tighten the lower bracket to specified
torque. If torqued too much, it may cause
the front fork to malfunction.
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)
STEERING

7 - 21
TUNSETTING
EC72H002
Suspension setting
Front fork
NOTE:
If any of the following symptoms is experienced with the standard position as the base, make
resetting by reference to the adjustment procedure given in the same chart.
Before any change, set the rear shock absorber sunken length to the standard figure 90 ~
100 mm (3.5 ~ 3.9 in).
SymptomSection
Check Adjust
JumpLarge
gapMedium
gapSmall
gap
Stiff over entire range

Compression damping
Oil level (oil amount)
SpringTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Decrease oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).
Replace with soft spring.
Unsmooth movement
over entire range

Outer tube
Inner tube
Under bracket tightening
torqueCheck for any bends, dents, and other noticeable
scars, etc. If any, replace affected parts.
Retighten to specified torque.
Poor initial
movement

Rebound damping
Oil sealTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Apply grease in oil seal wall.
Soft over entire range,
bottoming out

Compression damping
Oil level (oil amount)
SpringTurn adjuster clockwise (about 2 clicks) to increase
damping.
Increase oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).
Replace with stiff spring.
Stiff toward stroke end
Oil level (oil amount) Decrease oil level by about 5 mm (0.2 in).
Soft toward stroke end,
bottoming out
Oil level (oil amount) Increase oil level by about 5 mm (0.2 in).
Stiff initial movement
Compression dampingTurn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Low front, tending to
lower front posture

Compression damping
Rebound damping
Balance with rear end
Oil level (oil amount)Turn adjuster clockwise (about 2 clicks) to increase
damping.
Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Set sunken length for 95 ~ 100 mm (3.7 ~ 3.9 in) when
one passenger is astride seat (lower rear posture).
Increase oil level by about 5 mm (0.2 in).
“Obtrusive” front, tend-
ing to upper front pos-
ture

Compression damping
Balance with rear end
Spring
Oil lever (oil amount)Turn adjuster counterclockwise (about 2 clicks) to
decrease damping.
Set sunken length for 90 ~ 95 mm (3.5 ~ 3.7 in) when
one passenger is astride seat (upper rear posture).
Replace with soft spring.
Decrease oil level by about 5 ~ 10 mm (0.2 ~ 0.4 in).