2006 YAMAHA WR 450F transmission

4 - 94
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 3
2 Bearing 10 Refer to “REMOVAL POINTS”.
1

4 - 99
ENGCRANKCASE AND CRANKSHAFT
NOTE:
Hold the connecting rod at top dead center
with one hand while turning the nut of the
installing tool with the other. Operate the
installing tool until the crankshaft bottoms
against the bearing.
Before installing the crankshaft, clean the
contacting surface of crankcase.
CAUTION:
Do not use a hammer to drive in the crank-
shaft.
2. Check:
Shifter operation
Transmission operation
Unsmooth operation → Repair.
3. Install:
Oil strainer 1
Bolt (oil strainer) 2
4. Apply:
Sealant
On the crankcase (right) 1.
NOTE:
Clean the contacting surface of crankcase (left
and right) before applying the sealant.
Quick gasket®:
ACC-QUICK-GS-KT
YAMAHA Bond No. 1215:
90890-85505
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4 - 100
ENGCRANKCASE AND CRANKSHAFT
5. Install:
Dowel pin 1
O-ring 2
Crankcase (right)
To crankcase (left).
NOTE:
Fit the crankcase (right) onto the crankcase
(left). 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).
New
6. Tighten:
Hose guide 1
Clutch cable holder 2
Bolt (clutch cable holder)
Bolt (crankcase)
NOTE:
Tighten the crankcase tightening bolts in
stage, using a crisscross pattern.
7. Install:
Oil delivery pipe
O-ring
Bolt (oil delivery pipe 2)
8. Install:
Timing chain
Timing chain guide (rear)
Bolt (timing chain guide)
9. Remove:
Sealant
Forced out on the cylinder mating surface.
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)
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
New
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

4 - 101
ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
TRANSMISSION, SHIFT CAM AND SHIFT FORK
TRANSMISSION, SHIFT CAM AND SHIFT FORK
Extent of removal:
1 Shift fork, shift cam, main axle and drive axle removal
Extent of removal Order Part name Q’ty Remarks
TRANSMISSION, SHIFT CAM
AND SHIFT FORK REMOVAL
Preparation for removal Engine Refer to “ENGINE REMOVAL” section.
Separate the crankcase. Refer to “CRANKCASE AND CRANK-
SHAFT” section.
1 Shift fork 1 1
Refer to “REMOVAL POINTS”. 2 Shift fork 2 1
3 Shift fork 3 1
4Shift cam 1
5 Main axle 1
6 Drive axle 1
7 Collar 1
1

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ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
EC4H3000
REMOVAL POINTS
Shift fork, shaft cam and transmission
1. Remove:
Shift forks
Shift cam
Main axle
Drive axle
NOTE:
Tap lightly on the transmission drive axle and
shift cam with a soft hammer to remove.
Remove assembly carefully. Note the posi-
tion of each part. Pay particular attention to
the location and direction of shift forks.
EC4H4000
INSPECTION
EC4H4200
Gears
1. Inspect:
Matching dog a
Gear teeth b
Shift fork groove c
Wear/damage → Replace.
2. Inspect:
O-ring 1
Damage → Replace.
3. Check:
Gears movement
Unsmooth movement → Repair or
replace.
EC4H4600
Bearing
1. Inspect:
Bearing 1
Rotate inner race with a finger.
Rough spot/seizure → Replace.

ENG
4 - 102
DEMONTAGE-EINZELHEITEN
Schaltgabeln, Schaltwalze und
Getriebe
1. Demontieren:
Schaltgabeln
Schaltwalze
Eingangswelle
Ausgangswelle
HINWEIS:
Zum Ausbau leicht mit einem
Gummihammer auf die Getriebe-
Ausgangswelle und Schaltwalze
klopfen.
Die Baugruppe vorsichtig demon-
tieren. Die entsprechende Einbau-
lage sämtlicher Teile fest halten.
Der Lage und Ausrichtung der
Schaltgabeln besondere Achtung
schenken.
KONTROLLE
Zahnräder
1. Kontrollieren:
Schaltklauen
a
Verzahnung
b
Schaltgabel-Führungsnut
c
Verschlissen/beschädigt
→
Erneuern.
2. Kontrollieren:
O-Ring
1
Beschädigt
→ Erneuern.
3. Kontrollieren:
Beweglichkeit der Zahnräder
Fest
→ Instand setzen, ggf.
erneuern.
Lager
1. Kontrollieren:
Lager
1
Den Innenlaufring mit den Fin-
gern drehen.
Stockend/fest
→ Erneuern. POINTS DE DEPOSE
Fourchette de sélection, tambour et
boîte de vitesses
1. Déposer:
Fourchettes de sélection
Tambour
Arbre primaire
Arbre secondaire
N.B.:
Tapoter légèrement l’arbre secondaire
de transmission et le tambour à l’aide
d’un marteau en caoutchouc pour les
déposer.
Déposer l’ensemble avec précaution.
Prendre note de la position de chaque
pièce. Bien noter la position et l’orien-
tation des fourchettes de sélection.
CONTROLE
Pignons
1. Contrôler:
Crabot d’accouplement a
Dents du pignon b
Gorge de fourchette de sélection
c
Usure/endommagement → Rem-
placer.
2. Contrôler:
Joint torique 1
Endommagement → Remplacer.
3. Contrôler:
Rotation des pignons
Mouvement irrégulier → Répa-
rer ou remplacer.
Roulement
1. Contrôler:
Roulement 1
Faire tourner la cage interne avec
le doigt.
Rugosité/grippage → Remplacer.PUNTOS DE DESMONTAJE
Horquilla de cambio, leva de cambio y
caja de cambios
1. Extraer:
Horquillas de cambio
Leva de cambio
Eje principal
Eje posterior
NOTA:
Golpee ligeramente el eje de transmi-
sión de la caja de cambios y la leva de
cambio con un mazo blando para
extraerlos.
Extraiga el conjunto con cuidado.
Anote la posición de cada pieza.
Preste mucha atención a la situación y
dirección de las horquillas de cambio.
COMPROBACIÓN
Engranajes
1. Comprobar:
Desplazable correspondiente a
Dientes de engranaje b
Ranura de la horquilla de cambio
c
Desgaste/daños → Cambiar.
2. Comprobar:
Junta tórica 1
Dañada → Cambiar.
3. Comprobar:
Movimiento de los engranajes
Movimiento no suave → Reparar
o cambiar.
Cojinete
1. Comprobar:
Cojinete 1
Gire la guía interior con un dedo.
Punto duro/agarrotamiento →
Cambiar.
BOITE DE VITESSES, TAMBOUR ET FOURCHETTES DE SELECTION
GETRIEBE, SCHALTWALZE UND SCHALTGABELN
CAJA DE CAMBIOS, LEVA DE CAMBIO Y HORQUILLA DE CAMBIO

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ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
EC4H4801
Shift fork, shift cam and segment
1. Inspect:
Shift fork 1
Wear/damage/scratches → Replace.
2. Inspect:
Shift cam 1
Segment 2
Bend/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.
ASSEMBLY AND INSTALLATION
Transmission
1. Install:
5th pinion gear (25T) 1
3rd pinion gear (16T) 2
Collar 3
4th pinion gear (20T) 4
2nd pinion gear (15T) 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.

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ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
2. Install:
2nd wheel gear (26T) 1
4th wheel gear (21T) 2
3rd wheel gear (21T) 3
5th wheel gear (21T) 4
1st wheel gear (29T) 5
O-ring 6
To drive axle 7.
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.
Apply the lithium soap base grease on the O-
ring.
3. Install:
Plain washer 1
Circlip 2
NOTE:
Be sure the circlip sharp-edged corner a is
positioned opposite side to the plain washer
and gear b.
Install the circlip with its ends c settled
evenly on the spline crests.
cc
New
4. Install:
Collar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
When installing the spacer into the crank-
case, pay careful attention to the crankcase
oil seal lip.