suspension YAMAHA YZ250F 2005 Owners Manual

GEN
INFO
1 - 18
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Frame construction
Combined seat and fuel tank
Exhaust system
Engine mounting
Steering Steering stem to
handlebar
Suspension Front Steering stem to front
fork
Rear For link type
Rear Installation of rear
shock absorber
Rear Installation of swing-
arm
Wheel Installation of wheel Front
Rear
Brake Front
Rear
Fuel system
Lubrication systemFrame to rear frame
Fuel tank to frame
Silencer to rear frame
Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Front fork to upper bracket
Front fork to lower bracket
Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Rear shock absorber to frame
Tightening of pivot shaft
Tightening of wheel axle
Tightening of axle holder
Tightening of wheel axle
Wheel to rear wheel sprocket
Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Tightening of brake hose holder
Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Fuel tank to fuel cock
Tightening of oil hose clamp
NOTE:
Concerning the tightening torque, refer to
“MAINTENANCE SPECIFICATIONS” section
in the CHAPTER 2.

GEN
INFO
POINTS DE VERIFICATION DES COUPLES DE SERRAGE
N.B.:
Pour les couples de serrage, se reporter à la section
“CARACTERISTIQUES D’ENTRETIEN” au
CHAPITRE 2.
Cadre
Selle et réservoir de carburant
Système d’échappement
Bâti moteur
Direction Colonne de direction
vers guidon
Suspension Avant Colonne de direction
vers fourche
Arrière Pour le modèle à timonerie
Arrière Installation de l’amortis-
seur arrière
Arrière Installation du bras
oscillant
Roue Installation de la roue Avant
Arrière
Frein Avant
Arrière
Circuit de carburant
Système de lubrificationCadre au cadre arrière
Réservoir de carburant au cadre
Silencieux au cadre arrière
Cadre au moteur
Support de moteur au moteur
Support de moteur au cadre
Colonne de direction au cadre
Colonne de direction au té supérieur
Té supérieur au guidon
Fourche au té supérieur
Fourche au té inférieur
Ensemble de timonerie
Timonerie au cadre
Timonerie à l’amortisseur arrière
Timonerie au bras oscillant
Amortisseur arrière au cadre
Serrage du boulon-pivot
Serrage de l’axe de roue
Serrage du support d’axe
Serrage de l’axe de roue
Roue au pignon de roue arrière
Etrier de frein à la fourche
Disque de frein à la roue
Serrage du boulon de raccord
Maître-cylindre de frein au guidon
Serrage de la vis de purge
Serrage du support de durit de frein
Pédale de frein au cadre
Disque de frein à la roue
Serrage du boulon de raccord
Maître-cylindre de frein au cadre
Serrage de la vis de purge
Serrage du support de durit de frein
Réservoir de carburant au robinet de carburan
t
Serrage du collier de durit d’huile
POINTS DE VERIFICATION DES COUPLES DE SERRAGE
1 - 18

SPEC
2 - 3 Transmission:
Primary reduction system Gear
Primary reduction ratio 57/17 (3.353)
Secondary reduction system Chain drive
Secondary reduction ratio 48/13 (3.692) (Except for EUROPE)
49/13 (3.769) (For EUROPE)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 30/14 (2.143)
2nd 28/16 (1.750)
3rd 29/20 (1.450)
4th 27/22 (1.227)
5th 25/24 (1.042)
Chassis:
USA, ZA,
AUS, NZEUROPE
(Except
for F)FCDN
Frame type Semi dou-
ble cradle← ← ←
Caster angle 27.1°← 27.2°←
Trail 116 mm
(4.57 in)117 mm
(4.61 in)119 mm
(4.69 in)118 mm
(4.65 in)
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) 100/90-19 57M (For USA, CDN, ZA, AUS, NZ
and F)
100/90-19 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

SPEC
2 - 12 CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension:
Front fork travel 300 mm (11.8 in) ----
Fork spring free length 465 mm (18.3 in) 460 mm (18.1 in)
Spring rate, STD K = 4.3 N/mm
(0.438 kg/mm, 24.5 lb/in)----
Optional spring/spacer Yes ----
Oil capacity 430 cm
3 (15.1 Imp oz, 14.5 US oz) ----
Oil grade Suspension oil “S1”----
Inner tube outer diameter 48 mm (1.89 in) ----
Front fork top end 5 mm (0.20 in) ----
Rear suspension: USA, CDN,
AUS, NZ, ZAEUROPE
Shock absorber travel 132 mm (5.20 in)← ----
Spring free length 260 mm
(10.24 in)← ----
Fitting length 250.5 mm
(9.86 in)248.5 mm
(9.78 in)----
240.5~ 258.5 mm
(9.47 ~ 10.18 in)← ----
Spring rate, STD K = 48.0 N/mm
(4.90 kg/mm,
274.4 lb/in)←----
Optional spring Yes← ----
Enclosed gas pressure 1,000 kPa
(10 kg/cm
2,
142 psi)← ----
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04 in)
MAINTENANCE SPECIFICATIONS

SPEC
2 - 3 Commande Pied gauche
Rapport de démultiplication: 1ère 30/14 (2,143)
2ème 28/16 (1,750)
3ème 29/20 (1,450)
4ème 27/22 (1,227)
5ème 25/24 (1,042)
Châssis: USA, ZA,
AUS, NZEUROPE
(Sauf F)FCDN
Type de cadre Simple
berceau
dédoublé← ← ←
Angle de chasse 27,1°← 27,2°←
Chasse 116 mm
(4,57 in)117 mm
(4,61 in)119 mm
(4,69 in)118 mm
(4,65 in)
Pneus:
Type A chambre à air
Taille (avant) 80/100-21 51M (USA, CDN, ZA, AUS, NZ et F)
80/100-21 51R (EUROPE sauf F)
Taille (arrière) 100/90-19 57M (USA, CDN, ZA, AUS, NZ et F)
100/90-19 NHS (EUROPE sauf F)
Pression de gonflage (avant et arrière) 100 kPa (1,0 kgf/cm
2, 15 psi)
Freins:
Type de frein avant Frein monodisque
Commande Main droite
Type de frein arrière Frein monodisque
Commande Pied droit
Suspension:
Suspension avant Fourche télescopique
Suspension arrière Bras oscillant (suspension monocross à bras)
Amortisseur:
Amortisseur avant Ressort hélicoïdal/amortisseur hydraulique
Amortisseur arrière Ressort hélicoïdal/pneumatique, amortisseur
hydraulique
Débattement des roues:
Débattement de roue avant 300 mm (11,8 in)
Débattement de roue arrière 315 mm (12,4 in)
Système électrique:
Système d’allumage Volant magnétique CDI
CARACTERISTIQUES GENERALES

SPEC
2 - 12 CHASSIS
Elément Standard Limite
Système de direction:
Type de roulement de direction Roulement à rouleaux coniques ----
Suspension avant:
Débattement de fourche 300 mm (11,8 in) ----
Longueur libre de ressort de fourche 465 mm (18,3 in) 460 mm (18,1 in)
Raideur de ressort, standard K = 4,3 N/mm
(0,438 kg/mm, 24,5 lb/in)----
Ressort/entretoise en option Oui ----
Capacité d’huile 430 cm
3 (15,1 Imp oz, 14,5 US oz) ----
Type d’huile Huile de fourche “S1”----
Diamètre extérieur du tube plongeur 48 mm (1,89 in) ----
Extrémité supérieure de la fourche 5 mm (0,20 in) ----
Suspension arrière: USA, CDN,
AUS, NZ, ZAEUROPE
Débattement d’amortisseur 132 mm (5,20 in)← ----
Longueur de ressort libre 260 mm
(10,24 in)← ----
Longueur de raccord 250,5 mm
(9,86 in)248,5 mm
(9,78 in)----
240,5 à 258,5 mm
(9,47 à 10,18 in)← ----
Raideur de ressort, standard K = 48,0 N/mm
(4,90 kg/mm,
274,4 lb/in)← ----
Ressort en option Oui← ----
Pression du gaz enfermé1.000 kPa
(10 kg/cm
2,
142 psi)← ----
Bras oscillant:
Limite de jeu du bras oscillant
Extrémité---- 1,0 mm (0,04 in)
CARACTERISTIQUES D’ENTRETIEN

3 - 2
INSP
ADJ
MAINTENANCE INTERVALS
SHIFT FORK, SHIFT CAM, GUIDE BAR
InspectInspect wear
ROTOR NUT
Retighten
EXHAUST PIPE, SILENCER, PRO-
TECTOR
Inspect and retighten
Clean
Replace * Whichever comes first
CRANK
Inspect and clean
CARBURETOR
Inspect, adjust and clean
SPARK PLUG
Inspect and clean
Replace
DRIVE CHAIN
Use chain lube
Chain slack: 48 ~ 58 mm
(1.9 ~ 2.3 in) Lubricate, slack, alignment
Replace
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolant Every two years
Inspect hoses
OUTSIDE NUTS AND BOLTS Refer to “STARTING
AND BREAK-IN” section
in the CHAPTER 1. Retighten
AIR FILTER
Clean and lubricate
Use foam air-filter oil or
equivalent oil
Replace
OIL FILTER
Replace
OIL STRAINER (frame)
Clean
FRAME
Clean and inspect
FUEL TANK, COCK
Clean and inspect
BRAKES
Adjust lever position and pedal height
Lubricate pivot point
Check brake disc surface
Check fluid level and leakage
Retighten brake disc bolts, caliper
bolts, master cylinder bolts and union
bolts
Replace pads
Replace brake fluid Every one year
FRONT FORKS
Inspect and adjust
Replace oil Suspension oil “S1”
Replace oil sealItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks


3

5 - 32
CHAS
EC554600
Outer tube
1. Inspect:
Outer tube 1
Score marks/wear/damage → Replace.
Adjuster
1. Inspect:
Adjuster 1
O-ring 2
Wear/damage → Replace.
EC555000
ASSEMBLY AND INSTALLATION
Front fork assembly
1. Wash the all parts in a clean solvent.
2. Stretch the damper assembly fully.
3. Fill:
Front fork oil 1
To damper assembly.
CAUTION:
Be sure to use recommended fork oil. If
other oils are used, they may have an
excessively adverse effect on the front
fork performance.
Never allow foreign materials to enter the
front fork.
Recommended oil:
Suspension oil “S1”
Oil capacity:
195 cm
3 (6.86 Imp oz, 6.59 US oz)
FRONT FORK

5 - 39
CHAS
29. Install:
Adjuster 1
To inner tube.
T R..55 Nm (5.5 m · kg, 40 ft · lb)
30. Fill:
Front fork oil 1
From outer tube top.
WARNING
Never fail to make the oil amount adjust-
ment between the maximum and minimum
amount and always adjust each front fork
to the same setting. Uneven adjustment
can cause poor handling and loss of stabil-
ity.
CAUTION:
Be sure to use recommended fork oil. If
other oils are used, they may have an
excessively adverse effect on the front
fork performance.
Never allow foreign materials to enter the
front fork.
Recommended oil:
Suspension oil “S1”
Standard oil amount:
245 cm
3 (8.62 Imp oz, 8.28 US oz)
Extent of adjustment:
200 ~ 300 cm
3
(7.04 ~ 10.6 Imp oz,
6.76 ~ 10.1 US oz)
31. Install:
Damper assembly 1
To outer tube.
NOTE:
Temporarily tighten the damper assembly.
FRONT FORK

7 - 14
TUNSETTING
Spring preload adjustment
The spring preload is adjusted by installing the
adjustment washer 1 between the spacer 2
and fork spring 3.
CAUTION:
Do not install three or more adjustment
washers for each front fork.
WARNING
Always adjust each front fork to the same
setting. Uneven adjustment can cause poor
handling and loss of stability.
ÈLoad
ÉFork stroke
1Without adjustment washer (standard)
21 adjustment washer
32 adjustment washers
Standard washer quantity:
Zero adjustment washers
Extent of adjustment:
Zero ~ 2 adjustment washers
EC72A001
Setting of spring after replacement
As the front fork setting can be easily affected
by rear suspension, take care so that the
machine front and rear are balanced (in posi-
tion, etc.) when setting the front fork.
1. Use of soft spring
Generally a soft spring gives a soft riding
feeling. Rebound damping tends to
become stronger and the front fork may
sink deeply over a series of gaps.
To set a soft spring:
Change the rebound damping.
Turn out one or two clicks.
Change the compression damping.
Turn in one or two clicks.