transmission oil YAMAHA YZ250F 2006 Manuale duso (in Italian)

CHAPTER 4
ENGINE
SEAT, FUEL TANK
AND SIDE COVERS...................................4-1
EXHAUST PIPE AND SILENCER..............4-3
RADIATOR.................................................4-6
CARBURETOR...........................................4-9
CAMSHAFTS............................................4-22
CYLINDER HEAD.....................................4-31
VALVES AND VALVE SPRINGS.............4-34
CYLINDER AND PISTON.........................4-43
CLUTCH....................................................4-50
OIL FILTER ELEMENT, WATER PUMP
AND RIGHT CRANKCASE COVER........4-57
BALANCER..............................................4-64
OIL PUMP.................................................4-67
KICK SHAFT AND SHIFT SHAFT...........4-73
CDI MAGNETO.........................................4-80
ENGINE REMOVAL..................................4-84
CRANKCASE AND CRANKSHAFT.........4-89
TRANSMISSION, SHIFT CAM
AND SHIFT FORK....................................4-98
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL........5-1
FRONT BRAKE AND REAR BRAKE......5-10
FRONT FORK...........................................5-26
HANDLEBAR............................................5-43
STEERING................................................5-49
SWINGARM..............................................5-54
REAR SHOCK ABSORBER.....................5-62

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, CDNEUROPE
(Except
for F)FAUS, NZ,
ZA
Frame type Semi dou-
ble cradle← ← ←
Caster angle 27.0°27.1°27.3°27.0°
Trail 115.4 mm
(4.54 in)117.7 mm
(4.63 in)119.1 mm
(4.69 in)115.4 mm
(4.54 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 310 mm (12.2 in)
Electrical:
Ignition system CDI magneto
GENERAL SPECIFICATIONS

SPEC
2 - 13 Bras oscillant:
Limite de jeu du bras oscillant
Extrémité---- 1,0 mm (0,04 in)
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 × 1,85/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 111 + 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
CARACTERISTIQUES D’ENTRETIEN

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
Inspect
OIL FILTER ELEMENT, OIL STRAINER
Clean
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
TIMING CHAIN SPROCKETS, TIMING
CHAIN
Check for wear on the
teeth and for damage. Inspect
Replace
PISTON
Inspect
Inspect crack
Inspect carbon deposits
and eliminate them. Clean
Replace
PISTON RING
InspectCheck ring end gap
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

INSP
ADJ
FREINS
Régler la position du levier et la hauteur
de la pédale
Graisser le point de pivot
Contrôler la surface du disque de frein
Contrôler le niveau de liquide et
l’absence de fuites
Resserrer les boulons du disque de frein,
de l’étrier, du maître-cylindre et les bou-
lons-raccords
Remplacer les plaquettes
Changer le liquide de frein Une fois par an
FOURCHES
Contrôler et régler
Remplacer l’huile Huile de fourche “S1”
Remplacer la bague d’étanchéité
BAGUE D’ETANCHEITE ET JOINT
ANTIPOUSSIERE DE FOURCHE
Nettoyer et lubrifier Graisse à base de lithium
GUIDE DE PROTECTION
Remplacer
AMORTISSEUR ARRIERE
(Après utilisa-
tion par temps
de pluie)
Contrôler et régler
Graisse au bisulfure de
molybdène
Lubrifier
Remplacer le siège de ressort Une fois par an
Resserrer
PATIN ET ROULEAUX DE CHAINE DE
TRANSMISSION
Contrôler
BRAS OSCILLANT
Graisse au bisulfure de
molybdène
Contrôler, lubrifier et resserrer
BRAS RELAIS, BIELLE
Graisse au bisulfure de
molybdène
Contrôler, lubrifier et resserrer
TETE DE FOURCHE
Contrôler le jeu et resserrer
Nettoyer et lubrifier Graisse à base de lithium
Remplacer le roulement
PNEUS, ROUES
Contrôler la pression de gonflage, le
voile de roue, l’usure des pneus et la ten-
sion des rayons
Resserrer le boulon du pignon
Contrôler les roulements
Remplacer les roulements
Lubrifier Graisse à base de lithium
ACCELERATEUR, CABLE DE COM-
MANDELubrifiant pour câbles
Yamaha ou huile moteur
SAE 10W-30
Contrôler la propreté et
l’usure du câble des gaz du
côté carburateur. Contrôler le cheminement et le raccorde-
ment
Lubrifier
Contrôler et nettoyer (câble des gaz)
LEVIER DE DEMARRAGE A CHAUD,
LEVIER D’EMBRAYAGE
Contrôler le jeuElémentAprès
rodageA cha-
que
course
Toutes les
trois cour-
ses
(ou 500 km)Toutes les
cinq courses
(ou
1.000 km)Selon
les be-
soinsRemarques
PROGRAMME D’ENTRETIEN
3 - 3

4 - 59
ENG
OIL FILTER ELEMENT, WATER PUMP AND RIGHT
CRANKCASE COVER
REMOVAL POINTS
Impeller shaft
1. Remove:
Impeller 1
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
2. Remove:
Oil seal 1
INSPECTION
Oil delivery pipe
1. Inspect:
Oil delivery pipe 1
Bend/damage → Replace.
Clogged → Blow.

4 - 91
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 2
2 Bearing 10 Refer to “REMOVAL POINTS”.
1

4 - 96
ENGCRANKCASE AND CRANKSHAFT
2. Check:
Shifter operation
Transmission operation
Unsmooth operation → Repair.
3. Install:
Oil strainer 1
Bolt (oil strainer) 2
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
4. Apply:
Sealant
On the right crankcase 1.
NOTE:
Clean the contacting surface of left and right
crankcase before applying the sealant.
5. Install:
Dowel pin 1
O-ring 2
Right crankcase
To left crankcase.
NOTE:
Fit the right crankcase onto the left crank-
case. Tap lightly on the case with soft ham-
mer.
When installing the crankcase, the connect-
ing rod should be positioned at TDC (top
dead center).
YAMAHA Bond No. 1215
(ThreeBond® No. 1215):
90890-85505

4 - 97
ENGCRANKCASE AND CRANKSHAFT
6. Tighten:
Hose guide 1
Clutch cable holder 2
Bolt (crankcase) 3
NOTE:
Tighten the crankcase tightening bolts in
stage, using a crisscross pattern.
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
7. Install:
Oil delivery pipe 2 1
O-ring 2
Bolt (oil delivery pipe 2) 3
NOTE:
Apply the lithium soap base grease on the O-
rings.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
8. Install:
Timing chain 1
Timing chain guide (intake side) 2
Bolt (timing chain guide) 3
9. Remove:
Sealant
Forced out on the cylinder mating sur-
face.
10. Apply:
Engine oil
To the crank pin, bearing and oil delivery
hole.
11. Check:
Crankshaft and transmission operation.
Unsmooth operation → Repair.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4 - 100
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
EC4H4810
Shift fork, shift cam and segment
1. Inspect:
Shift fork 1
Wear/damage/scratches → Replace.
2. Inspect:
Shift cam 1
Segment 2
Wear/damage → Replace.
3. Check:
Shift fork movement
Unsmooth operation → Replace shift
fork.
NOTE:
For a malfunctioning shift fork, replace not only
the shift fork itself but the two gears each adja-
cent to the shift fork.
EC4H5000
ASSEMBLY AND INSTALLATION
Transmission
1. Install:
5th pinion gear (24T) 1
3rd pinion gear (20T) 2
Collar 3
4th pinion gear (22T) 4
2nd pinion gear (16T) 5
To main axle 6.
NOTE:
Apply the molybdenum disulfide oil on the
inner and end surface of the idler gear and on
the inner surface of the sliding gear, then
install.