lock YAMAHA YZ250LC 2002 Owner's Guide

4-61
ENGINE REMOVALENG
Extent of removal:1Engine removal
Extent of removal Order Part name Q’ty Remarks
1 Chain cover 1
2 Nut (drive sprocket) 1
3 Lock washer 1 Refer to “REMOVAL POINTS”.
4 Drive sprocket 1
5 Clip 1
6 Bolt (brake pedal) 1
7 Brake pedal 1
8 Engine bracket 2
9 Engine mounting bolt 3
10 Pivot shaft 1 Remove completely.
11 Engine 1 Refer to “REMOVAL POINTS”.
1





26 Nm (2.6 m•kg, 19 ft•lb)
69 Nm (6.9 m•kg, 50 ft•lb)
34 Nm (3.4 m•kg, 24 ft•lb)
69 Nm (6.9 m•kg, 50 ft•lb)
75 Nm (7.5 m•kg, 54 ft•lb)
8 Nm (0.8 m•kg, 5.8 ft•lb)
85 Nm (8.5 m•kg, 61 ft•lb)
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4-62
ENGINE REMOVALENG
EC4M3340
Engine removal
NOTE:
Make sure that the couplers, hoses and cables
are disconnected.
1. Lift the engine 1up to the point where the
engine’s mounting front does not contact the
bracket on the frame.
2. Remove the engine 1aslant and upward
while inclining it toward the kick crank side
so that the engine’s mounting top does not
contact the bracket on the frame.
EC4M3000
REMOVAL POINTS
EC4F3100
Drive sprocket
1. Remove:
9Nut (drive sprocket) 1
9Lock washer 2
NOTE:
9Straighten the lock washer tab.
9Loosen the nut while applying the rear brake.
2. Remove:
9Drive sprocket 1
9Drive chain 2
NOTE:
Remove the drive sprocket together with the
drive chain.
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4-64
ENGINE REMOVALENG
4. Install:
9Chain guide 1
9Chain cover 2
9Screw (chain cover) 3 2. Install:
9Lock washer 1
9Nut (drive sprocket) 2
NOTE:
Tighten the nut while applying the rear brake.
3. Bend the lock washer tab to lock the nut.
8 Nm (0.8 m•kg, 5.8 ft•lb)
75 Nm (7.5 m•kg, 54 ft•lb)
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4-66
CRANKCASE AND CRANKSHAFTENG
NOTE:
9Make appropriate bolts 3as shown available
by yourself and attach the tool with them.
9Fully tighten the tool holding bolts, but make
sure the tool body is parallel with the case. If
necessary, one screw may be backed out
slightly to level tool body.
9As pressure is applied, alternately tap on the
front engine mounting boss and transmission
shafts.
cC
Use soft hammer to tap on the case half.
Tap only on reinforced portions of case. Do
not tap on gasket mating surface. Work
slowly and carefully. Make sure the case
halves separate evenly. If one end “hangs
up”, take pressure off the push screw,
realign, and start over. If the cases do not
separate, check for a remaining case
screw or fitting. Do not force.
EC4N3000
REMOVAL POINTS
EC4N3100
Segment
1. Remove:
9Bolt (segment) 1
9Segment 2
NOTE:
Turn the segment counterclockwise until it stops
and loosen the bolt.
EC4N3212
Crankcase
1. Remove:
9Crankcase (right) 1
Use the crankcase separating tool 2.
Crankcase separating tool:
YU-1135-A/90890-01135
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4-71
CRANKCASE AND CRANKSHAFTENG
8. Tighten:
9Segment 1
9Bolt (segment) 2
NOTE:
9When installing the segment onto the shift cam
3, align the punch mark awith the dowel pin
b.
9Turn the segment clockwise until it stops and
tighten the bolt.
30 Nm (3.0 m•kg, 22 ft•lb)
7. Install:
9Tension spring 1
9Holder 2
9Bolt (holder) 3
NOTE:
Install the holder so that it contacts the projec-
tion aon the crankcase (right).
10 Nm (1.0 m•kg, 7.2 ft•lb)
9. Remove:
9Sealant
Forced out on the cylinder mating surface.
10. Apply:
9Engine oil
To the crank pin, bearing, oil delivery hole
and connecting rod big end washer.
11. Check:
9Crankshaft and transmission operation
Unsmooth operation
Repair.
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5-9
CHASFRONT WHEEL AND REAR WHEEL
8. Install:
9Chain puller (right) 1
9Plain washer 2
9Nut (wheel axle) 3
NOTE:
Temporarily tighten the nut (wheel axle) at this
point.
9. Adjust:
9Drive chain slack a
Refer to “DRIVE CHAIN SLACK ADJUSTMENT”
section in the CHAPTER 3.
10. Tighten:
9Nut (wheel axle) 1
9Locknut 2
125 Nm (12.5 m•kg, 90 ft•lb)
Drive chain slack :
40~50 mm (1.6~2.0 in)
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5-14
CHASFRONT BRAKE AND REAR BRAKE
EC5A3000
REMOVAL POINTS
EC5A3100
Brake fluid
1. Remove:
[Front]
9Master cylinder cap 1
[Rear]
9Reservoir tank cap 1
9Protector
NOTE:
Do not remove the diaphragm.
AFront
BRear
2. Connect the transparent hose 1to the
bleed screw 2and place a suitable contain-
er under its end.
AFront
BRear
3. Loosen the bleed screw and drain the brake
fluid while pulling the lever in or pushing
down on the pedal.
cC
9
Do not reuse the drained brake fluid.
9Brake fluid may erode painted surfaces
or plastic parts. Always clean up spilled
fluid immediately.
EC533301
Caliper piston
1. Remove:
9Caliper piston
Use compressed air and proceed carefully.
w
9
Cover piston with rag and use extreme cau-
tion when expelling piston from cylinder.
9Never attempt to pry out piston.
AFront
BRear
Caliper piston removal steps:
9Insert a piece of rag into the caliper to
lock one caliper.
9Carefully force the piston out of the
caliper cylinder with compressed air.
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5-25
CHASFRONT BRAKE AND REAR BRAKE
2. Install:
9Brake hose holder 1
9Screw (brake hose holder) 2
cC
After installing the brake hose holders,
make sure the brake hose does not contact
the spring (rear shock absorber). If it does,
correct its twist.
EC5A5600
Brake fluid
1. Fill:
9Brake fluid
Until the fluid level reaches “LOWER” level
line a.
w
9Use only the designated quality brake fluid:
otherwise, the rubber seals may deterio-
rate, causing leakage and poor brake per-
formance.
9Refill with the same type of brake fluid;
mixing fluids may result in a harmful chemi-
cal reaction and lead to poor performance.
9Be careful that water does not enter the
master cylinder when refilling. Water will
significantly lower the boiling point of the
fluid and may result in vapor lock.
cC
Brake fluid may erode painted surfaces or
plastic parts. Always clean up spilled fluid
immediately.
AFront
BRear
Recommended brake fluid:
DOT #4
1 Nm (0.1 m•kg, 0.7 ft•lb)
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5-25
CHAS
FREIN AVANT ET FREIN ARRIERE
VORDERRADBREMSE UND HINTERRADBREMSE
FRENO ANTERIORE E FRENO POSTERIORE
2. Einbauen:
9Bremsschlauchhalter 1
9Schraube (Bremsschlauchhal-
ter) 2
dD
Nachdem die Bremsschlauchhalter
eingebaut wurden, darauf achten,
daß der Bremsschlauch die Feder
(Hinterrad-Stoßdämpfer) nicht
berührt. Anderenfalls die Verdre-
hung berichtigen.
Bremsflüssigkeit
1. Füllen:
9Bremsflüssigkeit
Bis der Flüssigkeitsstand die
Standlinie „LOWER“ a
erreicht.
W
9Nur bezeichnete Qualitätsbrems-
flüssigkeit verwenden; anderen-
falls können die Gummidichtun-
gen angegriffen werden, wodurch
Undichtheiten und schlechte
Bremswirkung entstehen können.
9Zum Nachfüllen dieselbe Brems-
flüssigkeit verwenden; das
Mischen von Bremsflüssigkeiten
kann schädliche chemische Vor-
gänge hervorrufen und zu
schlechter Bremsleistung führen.
9Man achte darauf, daß beim Nach-
füllen kein Wasser in den Steuer-
zylinder gelangt. Wasser setzt den
Siedepunkt erheblich herab und
kann Dampfblasenbildung verur-
sachen.
dD
Bremsflüssigkeit kann lackierte
Flächen oder Plastikteile angreifen.
Deshalb ist vergossene Bremsflüs-
sigkeit sofort abzuwischen.
AVorne
BHinten
2. Monter:
9Support de tuyau de frein 1
9
Vis (support de tuyau de frein) 2
fF
Après avoir installé les supports de
tuyau de frein, s’assurer que le tuyau
de frein ne touche pos le ressort
(amortisseur arrière) S’il le touche,
corriger le coude.
Liquide de frein
1. Remplir:
9Liquide de frein
Jusqu’à ce que le liquide
atteigne le niveau “LOWER”
a.
XG
9La qualité du liquide de frein utilisé
doit être conforme aux normes spé-
cifiées, sinon les joints en caout-
chouc risquent de se détériorer, ce
qui causera des fuites et un mauvais
fonctionnement du frein.
9Toujours utiliser la même marque
de liquide de frein. Le mélange de
liquides de marques différentes
risque de provoquer une réaction
chimique nuisible au fonctionne-
ment du frein.
9Lorsqu’on ajoute du liquide, faire
attention de ne pas laisser pénétrer
de l’eau dans le maître-cylindre.
L’eau risque d’abaisser fortement
le point d’ébullition et de provoquer
le phénomène appelé “VAPOR
LOCK”.
fF
Le liquide de frein attaque les sur-
faces peintes et le plastique. Si on en
renverse, il faut l’essuyer immédiate-
ment.
AAvant
BArrière2. Installare:
9Supporto del tubo flessibile del
freno 1
9Vite (supporto del tubo flessibi-
le del freno) 2
iI
Dopo avere installato i supporti del
tubo flessibile del freno, assicurarsi
che il tubo flessibile del freno non
tocchi la molla (ammortizzatore
posteriore). Se lo fa, correggerne la
torsione.
IC5A5600
Liquido per freni
1. Riempire:
9Liquido per freni
Finché il livello del liquido rag-
giunge la linea di livello
“LOWER” a.
T
9Usare soltanto il liquido per freni
della qualità indicata: altrimenti, le
tenute in gomma possono deterio-
rarsi, provocando perdite e uno
scarso rendimento frenante.
9Rabboccare con lo stesso tipo di
liquido per freni; miscelare liquidi
diversi può portare a una reazione
chimica nociva e comporta uno
scarso rendimento.
9Fare attenzione che, durante il rab-
bocco, non entri acqua nel cilindro
principale. L'acqua abbasserà note-
volmente il punto di ebollizione del
liquido e può comportare un tam-
pone di vapore.
iI
Il liquido per freni può erodere le
superfici verniciate o le parti in pla-
stica. Ripulire sempre immediata-
mente il liquido versato.
AAnteriore
BPosteriore
Liquide de frein recom-
mandé:
DOT #4Empfohlene Bremsflüs-
sigkeit:
DOT Nr. 4Liquido per freni racco-
mandato:
DOT No. 4
1 Nm (0,1 m•kg, 0,7 ft•lb)
1 Nm (0,1 m•kg, 0,7 ft•lb)
1 Nm (0,1 m•kg, 0,7 ft•lb)
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5-29
CHASFRONT FORK
EC556000
HANDLING NOTE
NOTE:
The front fork requires careful attention. So it is
recommended that the front fork be maintained
at the dealers.
cC
To prevent an accidental explosion of air,
the following instructions should be ob-
served:
9The front fork with a built-in piston rod
has a very sophisticated internal con-
struction and is particularly sensitive to
foreign material.
Use enough care not to allow any foreign
material to come in when the oil is re-
placed or when the front fork is disassem-
bled and reassembled.
9Before removing the cap bolts or front
forks, be sure to extract the air from the air
chamber completely.
EC553000
REMOVAL POINTSEC553151
Cap bolt
1. Remove:
9Cap bolt 1
From the outer tube.
NOTE:
Before removing the front fork from the machine,
loosen the cap bolt.
2. Remove:
9Cap bolt 1
NOTE:
9While compressing the fork spring, set the thin
type spanners 2between the spacer 3and
spring guide 4.
9Hold the locknut 5and remove the cap
bolt.
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