lock YAMAHA YZ250LC 2004 Owner's Guide

4-57
CDI MAGNETOENG
EC4L5000
ASSEMBLY AND INSTALLATION
EC4L5172
CDI magneto
1. Install:
9Stator 1
9Screw (stator) 2
NOTE:
Temporarily tighten the screw (stator) at this
point.
2. Remove:
9Rotor 1
Use the flywheel puller 2.
NOTE:
When installing the flywheel puller, turn it coun-
terclockwise.
EC4L3000
REMOVAL POINTS
EC4L3102
Rotor
1. Remove:
9Nut (rotor) 1
9Plain washer 2
Use the rotor holding tool 3.
EC4L4000
INSPECTION
EC4L4101
CDI magneto
1. Inspect:
9Rotor inner surface a
9Stator outer surface b
Damage
Inspect the crankshaft runout
and crankshaft bearing.
If necessary, replace CDI magneto and/or
stator.
EC4L4200
Woodruff key
1. Inspect:
9Woodruff key 1
Damage
Replace.
Rotor holding tool:
YU-1235/90890-01235
Flywheel puller:
YM-1189/90890-01189
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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)
64 Nm (6.4 m•kg, 46 ft•lb)
64 Nm (6.4 m•kg, 46 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)
34 Nm (3.4 m•kg, 24 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)
EC4M5341
Drive sprocket
1. Install:
9Drive sprocket 1
9Drive chain 2
NOTE:
Install the drive sprocket together with the drive
chain.
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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.
14 Nm (1.4 m•kg, 10 ft•lb)
6. Install:
9Bolt (crankcase) 1
NOTE:
Tighten the crankcase tightening bolts in stage,
using a crisscross pattern.
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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)
16 Nm (1.6 m•kg, 11 ft•lb)
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5-14
CHASFRONT BRAKE AND REAR BRAKE
EC5A3000
REMOVAL POINTS
EC5A3101
Brake fluid
1. Remove:
[Front]
9Master cylinder cap 1
[Rear]
9Master cylinder 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
9Do 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
9Cover 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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5-24
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.
EC5A5620
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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5-24
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.
IC5A5620
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, 0,7ft•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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