2006 YAMAHA YZ250F lock

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ENGBALANCER
BALANCER
Extent of removal:
1 Balancer shaft drive gear
2 Balancer shaft
Extent of removal Order Part name Q’ty Remarks
BALANCER REMOVAL
Preparation for removal Primary driven gear Refer to “CLUTCH” section.
Right crankcase cover Refer to “OIL FILTER ELEMENT,
WATER PUMP AND RIGHT CRANK-
CASE COVER” section.
Stator Refer to “CDI MAGNETO” section.
1 Nut (primary drive gear) 1
Refer to “REMOVAL POINTS”.
2 Nut (balancer shaft driven gear) 1
3 Lock washer 1
4 Primary drive gear 1
5 Balancer shaft drive gear 1
6 Lock washer 1
7 Balancer shaft driven gear 1
8 Balancer shaft 1 Refer to “REMOVAL POINTS”.
2
1
2

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ENGBALANCER
REMOVAL POINTS
Balancer shaft drive gear and balancer
shaft driven gear
1. Straighten the lock washer tab.
2. Loosen:
Nut (primary drive gear) 1
Nut (balancer shaft driven gear) 2
NOTE:
Place an aluminum plate a between the teeth
of the balancer shaft drive gear 3 and driven
gear 4.
Balancer shaft
1. Remove:
Balancer shaft 1
NOTE:
When removing the balancer shaft, align the
center a of the balancer shaft weight along
the line connecting the centers of the crank-
shaft and balancer shaft.
INSPECTION
Primary drive gear, balancer shaft drive
gear and balancer shaft driven gear
1. Inspect:
Primary drive gear 1
Balancer shaft drive gear 2
Balancer shaft driven gear 3
Wear/damage → Replace.
Balancer shaft
1. Inspect:
Balancer shaft
Cracks/damage → Replace.

ENG
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DEMONTAGE-EINZELHEITEN
Ausgleichswellen-Antriebsritzel
und -rad
1. Die Lasche der Sicherungs-
scheibe umbiegen.
2. Lockern:
Mutter (Primärantriebsritzel)
1
(Ausgleichswellen-Antriebs-
rad)
2
HINWEIS:
Ein Alu-Blechstück
a zwischen das
Antriebsritzel
3 und das Antriebs-
rad
4 klemmen.
Ausgleichswelle
1. Demontieren:
Ausgleichswelle
1
HINWEIS:
Zur Demontage der Ausgleichswelle
die Mitte
a des Ausgleichsgewichts
auf die Mitte der Ausgleichs- und
Kurbelwellen ausrichten.
KONTROLLE
Primärantriebsritzel, Ausgleichs-
wellen-Antriebsritzel und -rad
1. Kontrollieren:
Primärantriebsritzel
1
Ausgleichswellen-Antriebsrit-
zel
2
Ausgleichswellen-Antriebsrad
3
Verschlissen/beschädigt
→
Erneuern.
Ausgleichswelle
1. Kontrollieren:
Ausgleichswelle
Rissig/beschädigt
→ Erneu-
ern. POINTS DE DEPOSE
Pignon menant et pignon mené de
l’arbre de balancier
1. Redresser l’onglet de la rondelle-
frein.
2. Desserrer:
Ecrou (pignon menant de trans-
mission primaire) 1
Ecrou (pignon mené de l’arbre de
balancier) 2
N.B.:
Placer une plaque d’aluminium a entre
les dents du pignon menant de l’arbre de
balancier 3 et le pignon mené 4.
Arbre de balancier
1. Déposer:
Arbre de balancier 1
N.B.:
Pour déposer l’arbre de balancier, ali-
gner le centre a du contrepoids d’arbre
de balancier sur la ligne raccordant les
centres du vilebrequin et de l’arbre de
balancier.
CONTROLE
Pignon menant de transmission pri-
maire, pignon menant et pignon mené
de l’arbre de balancier
1. Contrôler:
Pignon menant de transmission
primaire 1
Pignon menant de l’arbre de
balancier 2
Pignon mené de l’arbre de balan-
cier 3
Usure/endommagement → Rem-
placer.
Arbre de balancier
1. Contrôler:
Arbre de balancier
Craquelures/endommagement →
Remplacer.PUNTI DI RIMOZIONE
Ingranaggi conduttore e condotto
dell’albero equilibratore
1. Spianare la linguetta della rondella
di bloccaggio.
2. Allentare:
Dado (ingranaggio conduttore
della trasmissione primaria) 1
Dado (ingranaggio condotto
dell’albero equilibratore) 2
NOTA:
Posizionare una piastra di alluminio a
tra i denti dell’ingranaggio conduttore
dell’albero equilibratore 3 e l’ingranag-
gio condotto 4.
Albero equilibratore
1. Togliere:
Albero equilibratore 1
NOTA:
Quando si rimuove l’albero equilibra-
tore, allineare il centro a del peso
dell’albero equilibratore lungo la linea
che collega i centri dell’albero motore e
dell’albero equilibratore.
CONTROLLO
Ingranaggio conduttore della trasmis-
sione primaria, ingranaggio condut-
tore dell’albero equilibratore e
ingranaggio condotto dell’albero equi-
libratore
1. Controllare:
Ingranaggio conduttore della tra-
smissione primaria 1
Ingranaggio conduttore
dell’albero equilibratore 2
Ingranaggio condotto dell’albero
equilibratore 3
Usura/danni → Sostituire.
Albero equilibratore
1. Controllare:
Albero equilibratore
Incrinature/danni → Sostituire.
BALANCIER
AUSGLEICHSWELLE
EQUILIBRATORE

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ENGBALANCER
ASSEMBLY AND INSTALLATION
Balancer shaft, balancer shaft drive gear
and balancer shaft driven gear
1. Install:
Balancer shaft 1
NOTE:
Apply the engine oil on the bearing.
When installing the balancer shaft, align the
center a of the balancer shaft weight along
the line connecting the centers of the crank-
shaft and balancer shaft.
2. Install:
Balancer shaft driven gear 1
NOTE:
Install the balancer shaft driven gear onto the
balancer shaft while aligning the punch mark
a on the balancer shaft driven gear with the
lower spline b on the balancer shaft end.
3. Install:
Balancer shaft drive gear 1
NOTE:
Align the punched mark a on the balancer
shaft drive gear with the punched mark b on
the balancer shaft driven gear 2.
Align the punched mark c on the balancer
shaft drive gear with the lower spline d on
the crankshaft end.
4. Install:
Lock washer 1
Nut (balancer shaft driven gear) 2
Primary drive gear 3
Nut (primary drive gear) 4
NOTE:
Install the primary drive gear with its stepped
side a facing the engine.
Place an aluminum plate b between the
teeth of the balancer shaft drive gear 5 and
driven gear 6.
5. Bend the lock washer tab.
T R..50 Nm (5.0 m · kg, 36 ft · lb)
T R..75 Nm (7.5 m · kg, 54 ft · lb)

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ENGKICK SHAFT AND SHIFT SHAFT
REMOVAL POINTS
Kick shaft assembly
1. Remove:
Kick shaft assembly 1
NOTE:
Unhook the torsion spring 2 from the hole a
in the crankcase.
EC4C3101
Shift guide and shift lever assembly
1. Remove:
Bolt (shift guide)
Shift guide 1
Shift lever assembly 2
NOTE:
The shift lever assembly is disassembled at
the same time as the shift guide.
EC4N3100
Segment
1. Remove:
Bolt (segment) 1
Segment 2
NOTE:
Turn the segment counterclockwise until it
stops and loosen the bolt.
CAUTION:
If the segment gets an impact, it may be
damaged. Take care not to give an impact
to the segment when removing the bolt.
INSPECTION
Kick shaft and ratchet wheel
1. Check:
Ratchet wheel 1 smooth movement
Unsmooth movement → Replace.
Kick shaft 2
Wear/damage → Replace.
Spring 3
Broken → Replace.
EC4C4300
Kick gear, kick idle gear and ratchet wheel
1. Inspect:
Kick gear 1
Kick idle gear 2
Ratchet wheel 3
Gear teeth a
Ratchet teeth b
Wear/damage → Replace.

ENG
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DEMONTAGE-EINZELHEITEN
Kickhebelwelle
1. Demontieren:
Kickhebelwelle
1
HINWEIS:
Die Torsionsfeder
2 aus der Boh-
rung
a im Kurbelgehäuse lösen.
Schaltführung und Schaltklinke
1. Demontieren:
Schaltführungs-Schraube
Schaltführung
1
Schaltklinke komplett
2
HINWEIS:
Schaltklinke und Schaltführung wer-
den gemeinsam zerlegt.
Stiftplatte
1. Demontieren:
Stiftplatten-Schraube
1
Stiftplatte
2
HINWEIS:
Die Stiftplatte bis zum Anschlag im
Gegenuhrzeigersinn drehen und die
Schraube lockern.
ACHTUNG:
Das Zahnsegment kann durch
einen Stoß beschädigt werden.
Beim Demontieren der Schraube
darauf achten, das Zahnsegment
vor Stößen zu schützen.
KONTROLLE
Kickhebelwelle und Klinkenrad
1. Kontrollieren:
Leichtgängigkeit des Klinken-
rads
1
Stockend
→ Erneuern.
Kickhebelwelle
2
Verschlissen/beschädigt
→
Erneuern.
Feder
3
Gebrochen
→ Erneuern.
Kickstarter-Ritzel, -Zwischenrad
und -Klinkenrad
1. Kontrollieren:
Kickstarter-Ritzel
1
Kickstarter-Zwischenrad
2
Klinkenrad
3
Verzahnung
a
Klinkenverzahnung
b
Verschlissen/beschädigt
→
Erneuern. POINTS DE DEPOSE
Arbre de kick complet
1. Déposer:
Arbre de kick complet 1
N.B.:
Décrocher le ressort de torsion 2 de
l’orifice a du carter.
Guide de sélecteur et levier de sélec-
teur complet
1. Déposer:
Boulon (guide de sélecteur)
Guide de sélecteur 1
Levier de sélecteur complet 2
N.B.:
Le levier de sélecteur complet se
démonte en même temps que le guide de
sélecteur.
Segment
1. Déposer:
Boulon (segment) 1
Segment 2
N.B.:
Tourner le segment dans le sens inverse
des aiguilles d’une montre jusqu’à la
butée et desserrer le boulon.
ATTENTION:
Si le segment reçoit un impact, il ris-
que d’être endommagé. Veiller à ne
pas heurter le segment lors de la
dépose du boulon.
CONTROLE
Arbre de kick et roue à rochet
1. Contrôler:
Mouvement libre de la roue à
rochet 1
Mouvement irrégulier → Rem-
placer.
Arbre de kick 2
Usure/endommagement → Rem-
placer.
Ressort 3
Cassé → Remplacer.
Pignon de kick, pignon fou de kick et
roue à rochet
1. Contrôler:
Pignon de kick 1
Pignon fou de kick 2
Roue à rochet 3
Dents du pignon a
Dents du rochet b
Usure/endommagement → Rem-
placer.PUNTI DI RIMOZIONE
Gruppo albero pedale
1. Togliere:
Gruppo albero pedale 1
NOTA:
Sganciare la molla di torsione 2 dal
foro a nel carter.
Gruppo guida del cambio e leva del
cambio
1. Togliere:
Bullone (guida del cambio)
Guida del cambio 1
Gruppo leva del cambio 2
NOTA:
Il gruppo leva del cambio viene disas-
semblato contemporaneamente alla
guida del cambio.
Segmento
1. Togliere:
Bullone (segmento) 1
Segmento 2
NOTA:
Ruotare il segmento in senso antiorario
finché non si blocca, quindi allentare il
bullone.
ATTENZIONE:
Se il segmento subisce un urto,
potrebbe danneggiarsi. Prestare atten-
zione a non urtare il segmento quando
si rimuove il bullone.
CONTROLLO
Albero pedale e ruota con cricchetto
1. Controllare:
Movimento uniforme ruota con
cricchetto 1
Movimento non uniforme →
Sostituire.
Albero pedale 2
Usura/danni → Sostituire.
Molla 3
Rotto → Sostituire.
Ingranaggio pedale, ingranaggio folle
pedale e ruota con cricchetto
1. Controllare:
Ingranaggio pedale 1
Ingranaggio folle pedale 2
Ruota con cricchetto 3
Denti dell’ingranaggio a
Denti del cricchetto b
Usura/danni → Sostituire.
ARBRE DE KICK ET AXE DE SELECTEUR
KICKHEBELWELLE UND SCHALTWELLE
ALBERO PEDALE E ALBERO DEL CAMBIO

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ENGKICK SHAFT AND SHIFT SHAFT
3. Install:
Spring guide 1
NOTE:
Slide the spring guide into the kick shaft, make
sure the groove a in the spring guide fits on
the stopper of the torsion spring.
4. Install:
Kick shaft assembly 1
Washer 2
NOTE:
Apply the molybdenum disulfide grease on
the contacting surfaces of the kick shaft stop-
per a and kick shaft ratchet wheel guide 3.
Apply the engine oil on the kick shaft.
Slide the kick shaft assembly into the crank-
case and make sure the kick shaft stopper a
fits into the kick shaft ratchet wheel guide.
5. Hook:
Torsion spring 1
NOTE:
Turn the torsion spring clockwise and hook
into the proper hole a in the crankcase.
Kick idle gear
1. Install:
Kick idle gear 1
Washer 2
Circlip 3
NOTE:
Apply the engine oil on the kick idle gear
inner circumference.
Install the kick idle gear with its depressed
side a toward you.

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ENGCDI MAGNETO
EC4L3000
REMOVAL POINTS
Rotor
1. Remove:
Nut (rotor) 1
Washer 2
Use the rotor holding tool 3.
2. Remove:
Rotor 1
Use the flywheel puller 2.
NOTE:
When installing the flywheel puller, turn it
counterclockwise.
Rotor holding tool:
YU-1235/90890-01235
Flywheel puller:
YM-1189/90890-01189
EC4L4000
INSPECTION
EC4L4101
CDI magneto
1. Inspect:
Rotor inner surface a
Stator outer surface b
Damage → Inspect the crankshaft runout
and crankshaft bearing.
If necessary, replace CDI magneto and/
or stator.
EC4L4200
Woodruff key
1. Inspect:
Woodruff key 1
Damage → Replace.