Oil YAMAHA YZ250F 2002 Owners Manual

4 - 99
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
2. Install:
2nd wheel gear (28T) 1
4th wheel gear (27T) 2
3rd wheel gear (29T) 3
5th wheel gear (25T) 4
1st wheel gear (30T) 5
O-ring 6
To drive axle 7.
NOTE:
Apply the molybdenum disulfide oil on the
1st, 2nd and 3rd wheel gears inner circum-
ference and on the end surface.
Apply the molybdenum disulfide oil on the
4th and 5th wheel gears inner circumfer-
ence.
Apply the lithium soap base grease on the O-
ring.
3. Install:
Washer 1
Circlip 2
NOTE:
Be sure the circlip sharp-edged corner a is
positioned opposite side to the washer and
gear b.
Be sure the circlip end c is positioned at
axle spline groove d.
4. Install:
Collar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
When installing the collar into the crankcase,
pay careful attention to the crankcase oil seal
lip.

4 - 100
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
5. Install:
Shift fork 1 (L) 1
Shift fork 2 (C) 2
Shift fork 3 (R) 3
Shift cam 4
To main axle and drive axle.
NOTE:
Apply the molybdenum disulfide oil on the
shift fork grooves.
Mesh the shift fork #1 (L) with the 4th wheel
gear 5 and #3 (R) with the 5th wheel gear
7 on the drive axle.
Mesh the shift fork #2 (C) with the 3rd pinion
gear 6 on the main axle.
6. Install:
Transmission assembly 1
To left crankcase 2.
NOTE:
Apply the engine oil on the bearings and guide
bars.
7. Check:
Shifter operation
Transmission operation
Unsmooth operation → Repair.

5 - 1
CHAS

EC500000
CHASSIS
EC590000
FRONT WHEEL AND REAR WHEEL
EC598000
FRONT WHEEL
FRONT WHEEL AND REAR WHEEL
Extent of removal:
1
Front wheel removal
2
Wheel bearing removal
3
Brake disc removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removal
FRONT WHEEL REMOVAL
Hold the machine by placing the
suitable stand under the engine.
WARNING

Support the machine securely so there is no
danger of it falling over.
1 Brake hose cover 1
2 Bolt (brake hose holder) 2 Only loosening.
3 Bolt (axle holder) 4 Only loosening.
4 Nut (front wheel axle) 1
5 Front wheel axle 1
6 Front wheel 1
7 Collar 2
8 Oil seal 2
9 Bearing 2 Refer to “REMOVAL POINTS”.
10Brake disc
1
2
31
3

5 - 2
CHAS

EC598100
REAR WHEEL
Extent of removal:
1
Rear wheel removal
2
Wheel bearing removal
3
Brake disc removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removal
REAR WHEEL REMOVAL
Hold the machine by placing the
suitable stand under the engine.
WARNING

Support the machine securely so there is no
danger of it falling over.
1 Nut (rear wheel axle) 1
2 Rear wheel axle 1
3 Drive chain puller 2
4 Rear wheel 1 Refer to “REMOVAL POINTS”.
5 Collar 2
6 Rear wheel sprocket 1
7 Oil seal 2
8 Circlip 1
9 Bearing 2 Refer to “REMOVAL POINTS”.
10Brake disc
1
2
31
3

FRONT WHEEL AND REAR WHEEL

5 - 3
CHAS

FRONT WHEEL AND REAR WHEEL
EC593000
REMOVAL POINTS
EC523101
Rear wheel
1. Remove:

Wheel
1

NOTE:

Push the wheel forward and remove the drive
chain
2
.
EC513201
Wheel bearing (if necessary)
1. Remove:

Bearing
1

NOTE:

Remove the bearing using a general bearing
puller
2
.
EC594000
INSPECTION
EC514100
Wheel
1. Measure:

Wheel runout
Out of limit
→
Repair/replace.
2. Inspect:

Bearing
Rotate inner race with a finger.
Rough spot/seizure
→
Replace.
NOTE:

Replace the bearings, oil seal and wheel collar
as a set.
Wheel runout limit:
Radial
1
: 2.0 mm (0.08 in)
Lateral
2
: 2.0 mm (0.08 in)

5 - 3
CHAS

ROUE AVANT ET ROUE ARRIERE
VORDER- UND HINTERRAD
RUOTA ANTERIORE E RUOTA POSTERIORE
AUSBAU
Hinterrad
1. Demontieren:

Rad
1

HINWEIS:

Das Rad nach vorne stoßen und die
Antriebskette
2
abnehmen.
Radlager (nach Bedarf)
1. Demontieren:

Lager
1

HINWEIS:

Die Lager mit einem Lageraustreiber
2
ausbauen.
PRÜFUNG
Rad
1. Messen:

Felgenschlag
Unvorschriftsmäßig
→

Instand setzen/Erneuern.
Max. Felgenschlag
Höhenschlag
1
:
2,0 mm
Seitenschlag
2
:
2,0 mm
2. Kontrollieren:

Lager
Den inneren Laufring mit
dem Finger drehen.
Schwergängigkeit/Freßspu-
ren
→
Erneuern.
HINWEIS:

Lager, Dichtringe und Hülse im Satz
erneuern.
POINTS DE DEPOSE
Roue arrière
1. Déposer:

Roue
1

N.B.:

Pousser la roue vers l’avant et déposer la
chaîne de transmission
2
.
Roulement de roue (si nécessaire)
1. Déposer:

Roulement
1
N.B.:
Déposer le roulement en utilisant un
arrache-roulement courant 2.
CONTROLE
Roue
1. Mesure:
Voile de roue
Hors limite → Réparer/rempla-
cer.
Limite de voile de la roue:
Radial 1: 2,0 mm
(0,08 in)
Latéral 2: 2,0 mm
(0,08 in)
2. Contrôler:
Roulement
Faire tourner la bague inté-
rieure avec le doigt.
Point dur/grippage → Rempla-
cer.
N.B.:
Changer à la fois les roulements, la
bague d’étanchéité et la collerette de
roue.PUNTI DI RIMOZIONE
Ruota posteriore
1. Rimuovere:
Ruota 1
NOTA:
Spingere la ruota in avanti e rimuovere
la catena di trasmissione 2.
Cuscinetto della ruota (se necessario)
1. Rimuovere:
Cuscinetto 1
NOTA:
Rimuovere il cuscinetto impiegando un
estrattore per cuscinetti 2.
ISPEZIONE
Ruota
1. Misurare:
Scentratura
Fuori limite → Riparare/sosti-
tuire.
Limite di disassamento
ruota:
Radiale 1: 2,0 mm
(0,08 in)
Laterale 2: 2,0 mm
(0,08 in)
2. Ispezionare:
Cuscinetto
Far ruotare l’anello interno con
un dito.
Punti rugosi/grippaggio →
Sostituire.
NOTA:
Sostituire in blocco i cuscinetti, il parao-
lio ed il collarino della ruota.

5 - 4
CHAS
ROUE AVANT ET ROUE ARRIERE
VORDER- UND HINTERRAD
RUOTA ANTERIORE E RUOTA POSTERIORE
Radachse
1. Messen:
Radachsschlag
Unvorschriftsmäßig →
Erneuern.
Die Meßuhr 1 verwenden.
HINWEIS:
Der Radachsschlag entspricht der
Hälfte der Meßuhranzeige.
WARNUNG
Nie versuchen, eine verbogene
Achse zu richten.
Max. Radachsschlag
0,5 mm
Bremsscheibe
1. Messen:
Bremsscheibenschlag (nur
Hinterrad-Bremsscheibe)
Die Meßuhr 1 verwenden.
Unvorschriftsmäßig → Fel-
genschlag prüfen.
Falls im Sollbereich, die
Bremsscheibe erneuern.
2. Messen:
Bremsscheibenstärke a
Unvorschriftsmäßig →
Erneuern.
Max. Bremsscheiben-
verzug
Hinten
0,15 mm
Bremsscheiben-Min-
deststärke
Vorn
3,0 mm
2,5 mm
Hinten
4,0 mm
3,5 mm
Axe de roue
1. Mesurer:
Déformation de l’axe de roue
Hors-spécification → Rempla-
cer.
Utiliser le comparateur 1.
N.B.:
La valeur de déformation est égale à la
moitié de la lecture du comparateur.
AVERTISSEMENT
Ne jamais tenter de redresser un axe
tordu.
Limite de déformation de
l’axe de roue:
0,5 mm (0,020 in)
Disque de frein
1. Mesurer:
Déflexion de disque de frein
(disque de frein arrière unique-
ment)
Utiliser le comparateur 1.
Hors spécification → Exami-
ner le voile de roue.
Si le voile de la roue est nor-
mal, changer le disque de frein.
2. Mesurer:
Epaisseur de disque de frein a
Hors limite → Remplacer.
Limite de déflexion de dis-
que:
Arrière:
:0,15 mm
(0,006 in)
Limite d’usure de disque:
Avant:
3,0 mm (0,12 in)
: 2,5 mm
(0,10 in)
Arrière:
4,0 mm (0,16 in)
: 3,5 mm
(0,14 in)
Asse della ruota
1. Misurare:
Deformazioni asse della ruota
Fuori specifica → Regolare.
Utilizzare un comparatore 1.
NOTA:
Il valore di deformazione corrisponde
alla metà del valore indicato dal compa-
ratore.
AVVERTENZA
Non tentare di raddrizzare un asse
deformato.
Limite di deformazione
dell’asse della ruota:
0,5 mm (0,020 in)
Disco freno
1. Misurare:
Deflessione disco del freno
(solo disco del freno poste-
riore)
Utilizzare un comparatore 1.
Fuori specifica → Ispezionare
il disassamento della ruota.
Se il disassamento è in buone
condizioni, sostituire il disco
del freno.
2. Misurare:
Spessore del disco del freno a
Fuori limite → Sostituire.
Limite di deflessione del
disco freno:
Posteriore:
: 0,15 mm
(0,006 in)
Spessore del disco freno:
Anteriore:
3,0 mm (0,12 in)
: 2,5 mm
(0,10 in)
Posteriore:
4,0 mm (0,16 in)
: 3,5 mm
(0,14 in)

5 - 5
CHAS

FRONT WHEEL AND REAR WHEEL
EC595000
ASSEMBLY AND INSTALLATION
Front wheel
1. Install:

Bearing (left)
1


Spacer
2


Bearing (right)
3


Oil seal
4

NOTE:


Apply the lithium soap base grease on the
bearing and oil seal lip when installing.

Use a socket that matches the outside diam-
eter of the race of the bearing.

Left side of bearing shall be installed first.

Install the oil seal with its manufacture’s
marks or numbers facing outward.
ACHTUNG:CAUTION:

Do not strike the inner race of the bearing.
Contact should be made only with the outer
race.
2. Install:
Brake disc 1
Bolt (brake disc) 2
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
3. Install:
Collar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
Install the collars with their projections a
facing the wheel.
4. Install:
Wheel
NOTE:
Install the brake disc 1 between the brake
pads 2 correctly.

5 - 7
CHASFRONT WHEEL AND REAR WHEEL
9. Install:
Brake hose cover 1
Washer 2
Bolt [brake hose cover (M8)] 3
Bolt [brake hose cover (M6)] 4
T R..16 Nm (1.6 m · kg, 11 ft · lb)
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
Rear wheel
1. Install:
Bearing (right) 1
Circlip 2
Spacer 3
Bearing (left) 4
Oil seal 5
NOTE:
Apply the lithium soap base grease on the
bearing and oil seal lip when installing.
Install the bearing with seal facing outward.
Use a socket that matches the outside diam-
eter of the race of the bearing.
Right side of bearing shall be installed first.
Install the oil seal with its manufacture’s
marks or numbers facing outward.
ACHTUNG:CAUTION:
Do not strike the inner race of the bearing.
Contact should be made only with the outer
race.
2. Install:
Brake disc 1
Bolt (brake disc) 2
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
T R..14 Nm (1.4 m · kg, 10 ft · lb)

5 - 8
CHAS
3. Install:
Rear wheel sprocket 1
Bolt (rear wheel sprocket) 2
Washer (rear wheel sprocket) 3
Nut (rear wheel sprocket) 4
NOTE:
Tighten the nuts in stage, using a crisscross
pattern.
T R..42 Nm (4.2 m · kg, 30 ft · lb)
FRONT WHEEL AND REAR WHEEL
4. Install:
Collar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
5. Install:
Wheel
NOTE:
Install the brake disc 1 between the brake
pads 2 correctly.
6. Install:
Drive chain 1
NOTE:
Push the wheel 2 forward and install the drive
chain.
7. Install:
Left drive chain puller 1
Wheel axle 2
NOTE:
Install the left drive chain puller, and insert
the wheel axle from left side.
Apply the lithium soap base grease on the
wheel axle.