tow YAMAHA YZ250LC 2001 Owners Manual

1-9
CONTROL FUNCTIONS
GEN
INFO
EC150000
CONTROL FUNCTIONS
EC151000
“ENGINE STOP” BUTTON
The “ENGINE STOP” button 1is located on the
left handlebar. Continue pushing the “ENGINE
STOP” button till the engine comes to a stop.
EC152000
CLUTCH LEVER
The clutch lever 1is located on the left handle-
bar; it disengages or engages the clutch. Pull
the clutch lever to the handlebar to disengage
the clutch, and release the lever to engage the
clutch. The lever should be pulled rapidly and
released slowly for smooth starts.
EC153000
SHIFT PEDAL
The gear ratios of the constant-mesh 5 speed
transmission are ideally spaced. The gears can
be shifted by using the shift pedal 1on the left
side of the engine.
EC154000
KICK STARTER
Rotate the kick starter 1away from the engine.
Push the starter down lightly with your foot until
the gears engage, then kick smoothly and force-
fully to start the engine. This model has a prima-
ry kick starter so the engine can be started in
any gear if the clutch is disengaged. In normal
practices, however, shift to neutral before start-
ing.
EC155001
THROTTLE GRIP
The throttle grip 1is located on the right han-
dlebar; it accelerates or decelerates the engine.
For acceleration, turn the grip toward you; for
deceleration, turn it away from you.
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1-10
CONTROL FUNCTIONS
GEN
INFO
EC156000
FRONT BRAKE LEVER
The front brake lever 1is located on the right
handlebar. Pull it toward the handlebar to acti-
vate the front brake.
EC157000
REAR BRAKE PEDAL
The rear brake pedal 1is located on the right
side of the machine. Press down on the brake
pedal to activate the rear brake.
EC158001
FUEL COCK
The fuel cock supplies fuel from the tank to car-
buretor while filtering the fuel. The fuel cock has
the two positions:
OFF: With the lever in this position, fuel will not
flow. Always return the lever to this posi-
tion when the engine is not running.
ON: With the lever in this position, fuel flows to
the carburetor. Normal riding is done with
the lever in this position.
EC159000
STARTER KNOB (CHOKE)
When cold, the engine requires a richer air-fuel
mixture for starting. A separate starter circuit,
which is controlled by the starter knob 1, sup-
plies this mixture. Pull the starter knob out to
open the circuit for starting. When the engine
has warmed up, push it in to close the circuit.
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1-17
CLEANING AND STORAGE
GEN
INFO
EC1B0000
CLEANING AND STORAGE
EC1B1000
CLEANING
Frequent cleaning of your machine will enhance
its appearance, maintain good overall perfor-
mance, and extend the life of many components.
1. Before washing the machine, block off the
end of the exhaust pipe to prevent water
from entering. A plastic bag secured with a
rubber band may be used for this purpose.
2. If the engine is excessively greasy, apply
some degreaser to it with a paint brush. Do
not apply degreaser to the chain, sprockets,
or wheel axles.
3. Rinse the dirt and degreaser off with a gar-
den hose; use only enough pressure to do
the job.
cC
Excessive hose pressure may cause water
seepage and contamination of wheel bear-
ings, front forks, brakes and transmission
seals. Many expensive repair bills have
resulted from improper high pressure
detergent applications such as those avail-
able in coin-operated car washers.
4. After the majority of the dirt has been hosed
off, wash all surfaces with warm water and a
mild detergent. Use an old toothbrush to
clean hard-to-reach places.
5. Rinse the machine off immediately with
clean water, and dry all surfaces with a soft
towel or cloth.
6. Immediately after washing, remove excess
water from the chain with a paper towel and
lubricate the chain to prevent rust.
7. Clean the seat with a vinyl upholstery clean-
er to keep the cover pliable and glossy.
8. Automotive wax may be applied to all paint-
ed or chromed surfaces. Avoid combination
cleaner-waxes, as they may contain abra-
sives.
9. After completing the above, start the engine
and allow it to idle for several minutes.
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1-17
NETTOYAGE ET RANGEMENT
REINIGEN UND LAGERUNG
PULITURA E IMMAGAZZINAMENTO
GEN
INFO
REINIGEN UND
LAGERUNG
REINIGEN
Häufiges Reinigen Ihrer Maschine
stellt gefälliges Aussehen und ausge-
zeichnetes Leistungsvermögen sicher
und bürgt für längere Lebensdauer
der Bauteile.
1. Vor dem Waschen der Maschine,
das Ende des Auspuffrohres ver-
schließen, um ein Eindringen von
Wasser zu vermeiden. Für die-
sen Zweck kann ein Plastkbeutel
mit einem Gummiband verwen-
det werden.
2. Falls der Motor stark verölt ist,
Entfettungsmittel mit einem Pin-
sel auftragen. Das Entfettungs-
mittel jedoch niemals auf Kette,
Kettenräder oder Radachsen auf-
tragen.
3. Schmutz und Entfettungsmittel
mit einem Wasserschlauch ab-
spülen; dabei übermäßigen Was-
serdruck vermeiden.
dD
Übermäßiger Wasserdruck kann das
Eindringen von Wasser und Verun-
reinigung der Radlager, Vorderradga-
bel, Bremsen und Getriebedichtun-
gen verursachen. Viele teure Repara-
turen sind die Folge von falscher
Anwendung von Hochdruckreini-
gungsmitteln, wie sie in Münzauto-
waschanlagen vorhanden sind.
4. Nachdem der grobe Schmutz
abgespült wurde, alle Flächen mit
warmem Wasser und mildem
Waschmittel abwaschen. Eine alte
Zahnbürste für schwer zugängli-
che Stellen verwenden.
5. Danach die Maschine sofort mit
Frischwasser abspülen und alle
Flächen mit einem weichen Lap-
pen trocknen.
6. Unmittelbar nach dem Waschen,
Wasser mit Hilfe von Papier-
handtüchern von der Kette entfer-
nen und die Kette schmieren, um
Rostbildung zu vermeiden.
7. Die Sitzbank mit für Vinyl geeigne-
tem Reinigungsmittel reinigen, um
die Polsterung im glänzenden
Zustand zu erhalten.
8. Alle lackierten und verchromten
Flächen dürfen mit Autowachs
behandelt werden. Niemals
jedoch Wachs mit Schleifkornrei-
niger verwenden, da sonst die
Lackflächen zerkratzt werden kön-
nen.
9. Nach Beendigung der obigen Rei-
nigung, den Motor starten und für
einige Minuten im Leerlauf betrei-
ben.
NETTOYAGE ET
RANGEMENT
NETTOYAGE
Un nettoyage fréquent de la machine
réhausserra son aspect, maintiendra ses
bonnes performances et augmentera la
durée de nombre de ses composants.
1. Avant de laver la moto, bouchez la
sortie du pot d’échappement pour
éviter l’introduction d’eau. Un
sachet plastique retenu par un élas-
tique fera l’affaire.
2. Si le moteur est fortement encras-
sé, appliquez un peu de dégrais-
sant au pinceau. Evitez tout
contact avec la chaîne, ses pignons
et les axes de roue.
3. Rincez la boue et le dégraissant
avec un tuyau d’arrosage, en utili-
sant juste la pression suffisante.
fF
Une pression excessive risque de pro-
voquer des infiltrations d’eau dans
les roulements des roues, la fourche
avant, des freins et les joints de la
transmission. Noter que bien des
notes de réparation onéreuses ont
résulté de l’emploi abusif des vapori-
sateurs de détergent à haute pression,
tels que ceux qui équipent les laveries
automatiques de voitures.
4. Après avoir chassé la majeure par-
tie de la boue, lavez toutes les sur-
faces avec de l’eau chaude et un
détergent neutre. Utilisez une
vieille brosse à dents pour
atteindre les endroits difficiles
d’accès.
5. Rincez immédiatement l’engin
avec de l’eau propre et séchez
toutes les surfaces avec un chiffon
doux.
6. Immédiatement après le lavage,
éliminez l’excès d’eau de la chaîne
avec des mouchoirs en papier et
lubrifiez la chaîne pour éviter
qu’elle ne rouille.
7. Nettoyez la selle avec un produit
pour meubles rembourrés pour que
sa housse reste souple et brillante.
8. Un encaustique pour automobile
peut être appliqué sur toutes les
surfaces peintes et chromées. Evi-
tez les liquiles de nettoyage à
encaustique, car ils contienment de
l’abrasif.
9. Les opérations ci-dessus termi-
nées, lancez le moteur et laissez-le
tourner pendant quelques minutes.
IC1B0000
PULITURA E IMMAGAZZI-
NAMENTO
IC1B1000
PULITURA
Una pulitura frequente del veicolo ne
migliorerà l’aspetto, manterrà buone
prestazioni generali e prolungherà la
durata di molti componenti.
1. Prima di lavare il veicolo, bloccare
l’estremità del tubo di scarico per
impedire che entri acqua. A questo
scopo si può usare un sacchetto di
plastica fissato con un elastico.
2. Se il motore è eccessivamente
grasso, applicarvi uno sgrassante
con un pennello. Non applicare
sgrassante sulla catena, sui roc-
chetti o sugli assi delle ruote.
3. Sciacquare via lo sporco e lo
sgrassante con una canna da giar-
dinaggio; usare soltanto la pressio-
ne necessaria a svolgere il lavoro.
iI
Una pressione eccessiva della canna
può provocare infiltrazioni d’acqua e
contaminazione dei cuscinetti delle
ruote, delle forcelle anteriori, dei
freni e dei dispositivi di tenuta della
trasmissione. Applicazioni di deter-
gente improprie ad alta pressione
come quelle disponibili negli autola-
vaggi a gettone hanno comportato
molte costose fatture di riparazione.
4. Dopo che la maggior parte dello
sporco è stata lavata via, lavare
tutte le superfici con acqua tiepida
e un detergente delicato. Usare un
vecchio spazzolino da denti per
pulire i punti difficili da raggiun-
gere.
5. Sciacquare immediatamente il vei-
colo con acqua pulita e asciugare
tutte le superfici con un asciuga-
mano o un panno morbido.
6. Immediatamente dopo il lavaggio,
togliere l’acqua in eccesso dalla
catena con un panno-carta e lubri-
ficare la catena per prevenire la
ruggine.
7. Pulire la sella con un pulitore per
rivestimenti in vinile per mantene-
re la copertura flessibile e lucida.
8. Su tutte le superfici verniciate o
cromate si può applicare cera per
autoveicoli. Evitare la combinazio-
ne pulitore-cere, poiché può conte-
nere abrasivi.
9. Dopo avere eseguito le operazioni
descritte più sopra, avviare il
motore e farlo girare al minimo
per diversi minuti.
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INSP
ADJ
3-5
ENGINE/COOLANT LEVEL INSPECTION/
COOLANT REPLACEMENT
EC350000
ENGINE
EC351011
COOLANT LEVEL INSPECTION
w
Do not remove the radiator cap 1 1
, drain
bolt and hoses when the engine and radia-
tor are hot. Scalding hot fluid and steam
may be blown out under pressure, which
could cause serious injury.
When the engine has cooled, place a thick
towel over the radiator cap, slowly rotate
the cap counterclockwise to the detent.
This procedure allows any residual pres-
sure to escape. When the hissing sound
has stopped, press down on the cap while
turning counterclockwise and remove it.
cC
Hard water or salt water is harmful to the
engine parts. You may use distilled water,
if you can’t get soft water.
1. Place the machine on a level place, and
hold it in an upright position.
2. Remove:
9Radiator cap
3. Check:
9Coolant level a
Coolant level lowÕAdd coolant.
1Radiator
EC353011
COOLANT REPLACEMENT
w
Do not remove the radiator cap when the
engine is hot.
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3-17
CHASSIS/BRAKE SYSTEM AIR BLEEDING
INSP
ADJ
EC360000
CHASSIS
EC361012
BRAKE SYSTEM AIR BLEEDING
w
Bleed the brake system if:
9The system has been disassembled.
9A brake hose has been loosened or removed.
9The brake fluid is very low.
9The brake operation is faulty.
A dangerous loss of braking performance may
occur if the brake system is not properly bleed.
1. Remove:
9Master cylinder cap
9Diaphragm
9Protector (rear brake)
2. Bleed:
9Brake fluid
Front
õRear
Air bleeding steps:
a. Add proper brake fluid to the reservoir.
b. Install the diaphragm. Be careful not to
spill any fluid or allow the reservoir to
overflow.
c. Connect the clear plastic tube
2tightly to
the caliper bleed screw 1.
d. Place the other end of the tube into a
container.
e. Slowly apply the brake lever or pedal sev-
eral times.
f. Pull the lever in or push down on the ped-
al. Hold the lever or pedal in position.
g. Loosen the bleed screw and allow the
lever or pedal to travel towards its limit.
h. Tighten the bleed screw when the lever or
pedal limit has been reached; then re-
lease the lever or pedal.
i. Repeat steps (e) to (h) until of the air
bubbles have been removed from the
system.
Bleed screw:
6 Nm (0.6 m•kg, 4.3 ft•lb)
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ENG
4-5
RADIATOR
EC456000
HANDLING NOTE
w
Do not remove the radiator cap when the
engine and radiator are hot. Scalding hot
fluid and steam may be blown out under
pressure, which could cause serious
injury.
When the engine has cooled, open the
radiator cap by the following procedure:
Place a thick rag, like a towel, over the radi-
ator cap, slowly rotate the cap counter-
clockwise to the detent. This procedure
allows any residual pressure to escape.
When the hissing sound has stopped,
press down on the cap while turning coun-
terclockwise and remove it.
EC453000
REMOVAL POINTS
EC453200
Panel
1. Remove:
9Panel 1
NOTE:
9Unhook the panel first on the outer side aand
then on the inner side.
9Take care not to bend the panel more than nec-
essary.
EC454000
INSPECTION
EC444100
Radiator
1. Inspect:
9Radiator core 1
Obstruction ÕBlow out with compressed air
through rear of the radiator.
Bent fin ÕRepair/replace.
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ENG
4-15
CARBURETOR AND REED VALVE
8. Install:
9Air vent hose [
R=580 mm (22.8 in)] 1
9Air vent hose [R=400mm (15.7 in)] 2
9Overflow hose [R=280mm (11.0 in)] 3
9Clamp 4
NOTE:
Install the air vent hoses and overflow hose to
the carburetor with their ends not having the cuts
atoward the carburetor.
9. Install:
9Jet needle 1
9Collar 2
9Spring 3
9Needle holder 4
To throttle valve 5.
NOTE:
Install the spring with its smaller dia. afacing
the collar.
10. Install:
9Throttle cable 1
9Mixing chamber top 2
9Spring (throttle valve) 3
9Ring 4
9Throttle valve 5
NOTE:
9While compressing the spring, connect the
throttle cable.
9Align the projection aon the ring with the
groove bin the needle holder 6.
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4-28
CYLINDER HEAD, CYLINDER AND PISTONENG
7. Install:
9O-ring 1
9Side holder 2
9Screw (side holder) 3
9YPVS breather hose 4
NOTE:
9Apply the lithium soap base grease on the O-
rings.
9Install the side holder with its projection a
facing upward.
8. Install:
9Gasket (power valve cover) 1
9Power valve cover 2
9Screw (power valve cover) 3
NOTE:
9Install the gasket with its cut afacing down-
ward and the seal print side toward the power
valve cover.
9Install the power valve cover so that the arrow
mark bfaces upward.
EC475233
Piston ring and piston
1. Install:
9Piston ring 1
NOTE:
9Take care not to scratch the piston or damage
the piston ring.
9Align the piston ring gap with the pin 2.
9After installing the piston ring, check the
smooth movement of it.
2. Install:
9Gasket (cylinder) 1
9Small end bearing 2
9Dowel pin 3
NOTE:
9Apply the engine oil onto the bearing (crank-
shaft and connecting rod) and connecting rod
big end washers.
9Install the gasket with the seal print side toward
the crankcase.
4 Nm (0.4 m•kg, 2.9 ft•lb)
4 Nm (0.4 m•kg, 2.9 ft•lb)
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4-37
CLUTCH AND PRIMARY DRIVEN GEARENG
5. Install:
9Friction plate 1
9Clutch plate 2
NOTE:
9Install the clutch plates and friction plates alter-
nately on the clutch boss, starting with a friction
plate and ending with a friction plate.
9Apply the transmission oil on the friction plates
and clutch plates.
6. Install:
9Bearing 1
9Plain washer 2
9Circlip 3
To push rod 1 4.
NOTE:
Apply the lithium soap base grease on the bear-
ing and plain washer.
7. Install:
9Push rod 2 1
9Push rod 1 2
NOTE:
9Apply the transmission oil on the ends of the
push rod 2.
9Install the push rod 2 with its smaller end a
toward you.
8. Install:
9Pressure plate 1
9. Install:
9Clutch spring 1
9Screw (clutch spring) 2
NOTE:
Tighten the screws in stage, using a crisscross
pattern.
10 Nm (1.0 m•kg, 7.2 ft•lb)
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