2002 YAMAHA YZ426F oil

4 - 96
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 crankcase (left) 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 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 disk
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 Chain puller 2
4 Rear wheel 1 Refer to “REMOVAL POINTS”.
5 Collar 2
6 Driven sprocket 1
7 Oil seal 2
8 Circlip 1
9 Bearing 2 Refer to “REMOVAL POINTS”.
10Brake disk
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
AUSBAU
Hinterrad
1. Demontieren:

Rad
1

HINWEIS:

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

Lager
1

HINWEIS:

Die Lager mit einem Lageraustreiber
2
aus-
bauen.
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/Freßspuren
→

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-roule-
ment courant
2
.
CONTROLE
Roue
1. Mesure:

Voile de roue
Hors limite
→
Réparer/changer.
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 intérieure avec le
doigt.
Point dur/grippage → Changer.
N.B.:
Changer à la fois les roulements, la bague d’étan-
chéité et la collerette de roue.

5 - 4
CHAS
ROUE AVANT ET ROUE ARRIERE
VORDER- UND HINTERRAD
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 → Felgenschlag
prüfen.
Falls im Sollbereich, die Bremsscheibe
erneuern.
2. Messen:
Bremsscheibenstärke a
Unvorschriftsmäßig → Erneuern.
Max. Bremsscheibenverzug
Standard
Hinten—0,15 mm
Bremsscheiben-Mindeststärke
Standard
Vorn 3,0 mm 2,5 mm
Hinten4,0 mm 3,5 mm
Axe de roue
1. Mesurer:
Les flexions de l’axe de roue
Hors-spécification → Changer.
Utiliser le comparateur 1.
N.B.:
La valeur de flexion est égale à la moitié de la lec-
ture du comparateur.
AVERTISSEMENT
Ne jamais tenter de redresser un axe tordu.
Limite de torsion 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 uniquement)
Utiliser le comparateur 1.
Hors spécification → Examiner le voile de
roue.
Si le voile de la roue est normal, changer le
disque de frein.
2. Mesurer:
Epaisseur de disque de frein a
Hors limite → Changer.
Limite de déflexion de disque:
Standard
Arrière—0,15 mm
(0,006 in)
Limite d’usure de disque:
Standard
Avant3,0 mm (0,12 in) 2,5 mm (0,10 in)
Arrière 4,0 mm (0,16 in) 3,5 mm (0,14 in)

5 - 5
CHAS

FRONT WHEEL AND REAR WHEEL
EC595000
ASSEMBLY AND INSTALLATION
EC595100
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.
New
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:
Hose cover 1
Plain washer 2
Bolt [hose cover (M8)] 3
Bolt [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)
EC5251A0
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.
New
New
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)