oil YAMAHA YZ250LC 2003 Owners Manual

EC085002
ILLUSTRATED SYMBOLS
(Refer to the illustration)
Illustrated symbols 1to 7are designed as
thumb tabs to indicate the chapter’s number and
content.
1
General information
2Specifications
3Regular inspection and adjustments
4Engine
5Chassis
6Electrical
7Tuning
Illustrated symbols 8to rare used to identify
the specifications appearing in the text.
8
With engine mounted
9Special tool
0Filling fluid
qLubricant
wTightening
eSpecified value, Service limit
rResistance (Ω), Voltage (V), Electric current (A)
Illustrated symbols tto oin the exploded dia-
grams indicate grade of lubricant and location of
lubrication point.
t
Apply transmission oil
yApply engine mixing oil
uApply molybdenum disulfide oil
iApply lightweight lithium-soap base grease
oApply molybdenum disulfide grease
Illustrated symbols pto ain the exploded dia-
grams indicate where to apply a locking agent
and where to install new parts.
p
Apply locking agent (LOCTITER)
aUse new one
GEN
INFO
12
3
5
74
6
8
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SPEC
INSP
ADJENG
CHASELEC
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ABGEBILDETEN SYMBOLE
(Siehe Abbildung)
Die abgebildeten Symbole 1bis 7
sind zur einfachen Auffindung der Sei-
ten mit Daumeneinkerbungen verse-
hen. Die Abschnittsnummer sowie der
lnhalt können sofort ersehen werden.
1Allgemein Angaben
2Technische Daten
3Regelmäßige Prüfung und
Einstellungen
4Motor
5Fahrgestell
6Elektrische Einrichtungen
7Tuning
Die abgebildeten Symbole von 8bis
rwerden zur Unterscheidung der
Spezifikationen in diesem Text
benutzt.
8Mit dem Motor eingebaut
9Spezialwerkzeug
0Einfüllen von Flüssigkeit
qSchmiermittel
wFestziehen (Anzugsmoment)
eVerschleißgrenze, Wartungs-
Toleranzgrenze
rWiderstand (Ω), Spannung (V),
elektrischer Strom (A)
Die abgebildeten Symbole tbis oin
der Explosionszeichnung zeigen die
Schmierstoffklasse sowie die
Schmierstellen an.
tGetriebeöl auftragen
yMotor-Mischöl auftragen
uMolybdändisulfid-Öl auftragen
iLeichtes Lithium-Fett auftragen
oMolybdändisulfid-Fett auftragen
Die abgebildeten Symbole pbis ain
der Explosionszeichnung zeigen die
Stellen, wo Sicherungslack aufzutra-
gen ist und neue Teile einzubauen
sind.
pSicherungslack (LOCTITE®)
auftragen
aNeues Teil verwenden
SYMBOLES GRAPHIQUES
(Voir l’illustration)
Les symboles graphiques 1à 7ser-
vent à repérer les différents chapitres et
à indiquer leur contenu.
1Renseignements généraux
2Caracteristiques
3Verification et réglages courants
4Moteur
5Partie cycle
6Partie électrique
7Mise au point
Les symboles graphiques 8á rper-
mettent d’identifier les spécifications
encadrées dans le texte.
8Avec de montage du moteur
9Outil spécial
0Liquide de remplissage
qLubrifiant
wSerrage
eValeur spécifiée, limite de service
rRésistance (Ω), tension (V), intensité (A)
Les symboles graphiques tà odans
les vues éclatées indiquent le grade de
lubrifiant et l’emplacement des points
de lubrification.
tAppliquer de l’huile de transmissionyAppliquer de l’huile de mélange du moteuruAppliquer de l’huile au bisulfure de molybdèneiAppliquer de la graisse fluide à base de savon
au lithium
oAppliquer de la graisse au bisulfure de
molybdène
Les symboles graphiques pet adans
les vues éclatées indiquent où appliquer
de l’agent bloquant et où installer de
nouveaux composants.
pAppliquer un agent de blocage
(LOCTITE®)
aUtiliser une pièce neuve
IC085002
SIMBOLI ILLUSTRATI
(Fare riferimento all’illustra-
zione)
I simboli illustrati da 1a 7sono pro-
gettati come linguette da sfogliare che
indichino il numero e il contenuto del
capitolo.
1Informazioni generali
2Specifiche
3Ispezione e regolazioni regolari
4Motore
5Telaio
6Parte elettrica
7Messa a punto
I simboli illustrati da 8a rvengono
usati per identificare le specifiche che
compaiono nel testo.
8Con motore montato
9Utensile speciale
0Liquido di riempimento
qLubrificante
wSerraggio
eValore specificato, limite di servizio
rResistenza (Ω), Tensione (V), Corrente
elettrica (A)
I simboli da ta oillustrati nei dia-
grammi esplosi indicano la qualità di
lubrificante e la posizione del punto di
lubrificazione.
tApplicare olio per trasmissioneyApplicare olio per miscela per motoriuApplicare olio a base di bisolfuro di molibdenoiApplicare grasso leggero a base di sapone di
litio
oApplicare grasso a base di bisolfuro di
molibdeno
I simboli pe aillustrati nei diagram-
mi esplosi indicano dove applicare
l’agente bloccante e dove montare il
pezzo di ricambio.
pApplicare agente bloccante
(LOCTITE®)
aUsare un pezzo nuovo
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EC0A0000
CONTENTS
CHAPTER 1
GENERAL INFORMATION
DESCRIPTION............................................1-1
MACHINE IDENTIFICATION......................1-2
IMPORTANT INFORMATION.....................1-3
CHECKING OF CONNECTION..................1-6
SPECIAL TOOLS........................................1-7
CONTROL FUNCTIONS.............................1-9
FUEL AND ENGINE MIXING OIL.............1-12
STARTING AND BREAK-IN.....................1-13
TORQUE-CHECK POINTS.......................1-16
CLEANING AND STORAGE....................1-17
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS....................2-1
MAINTENANCE SPECIFICATIONS...........2-3
GENERAL TORQUE SPECIFICATIONS..2-12
DEFINITION OF UNITS............................2-12
CABLE ROUTING DIAGRAM..................2-13
CHAPTER 3
REGULAR INSPECTION
AND ADJUSTMENTS
MAINTENANCE INTERVALS.....................3-1
PRE-OPERATION INSPECTION AND
MAINTENANCE..........................................3-4
ENGINE.......................................................3-5
CHASSIS...................................................3-17
ELECTRICAL............................................3-38
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1-1
DESCRIPTION
GEN
INFO
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1Clutch lever
2“ENGINE STOP” button
3Front brake lever
4Throttle grip
5Radiator cap
6Fuel tank cap
7Kick starter
8Fuel tank
9Radiator
0Coolant drain bolt
qCheck bolt (Transmission oil level)
wRear brake pedal
eValve joint
rFuel cock
tStarter knob
yDrive chain
uAir cleaner
iShift pedal
oFront fork
NOTE:
9The machine you have purchased may differ
slightly from those shown in the following.
9Designs and specifications are subject to
change without notice.
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1-4
IMPORTANT INFORMATION
GEN
INFO
EC133000
GASKETS, OIL SEALS AND O-RINGS
1. All gaskets, oil seals, and O-rings should be
replaced when an engine is overhauled. All
gasket surfaces, oil seal lips, and O-rings
must be cleaned.
2. Properly oil all mating parts and bearings
during reassembly. Apply grease to the oil
seal lips.
EC134000
LOCK WASHERS/PLATES AND COTTER
PINS
1. All lock washers/plates 1and cotter pins
must be replaced when they are removed.
Lock tab(s) should be bent along the bolt or
nut flat(s) after the bolt or nut has been
properly tightened.
EC135001
BEARINGS AND OIL SEALS
1. Install the bearing (s) 1and oil seal (s) 2
with their manufacturer’s marks or numbers
facing outward. (In other words, the
stamped letters must be on the side
exposed to view.) When installing oil seal(s),
apply a light coating of light-weight lithium
base grease to the seal lip(s). Oil the bear-
ings liberally when installing.
cC
Do not use compressed air to spin the
bearings dry. This causes damage to the
bearing surfaces.
EC132000
ALL REPLACEMENT PARTS
1. We recommend to use Yamaha genuine
parts for all replacements. Use oil and/or
grease recommended by Yamaha for
assembly and adjustment.
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1-8
SPECIAL TOOLS
GEN
INFO
Part number Tool name / How to use IIIustration
YU-33975, 90890-01403 Ring nut wrenchYU-33975 90890-01403
This tool is used when tighten the steering ring nut
to specification.
YM-1423, 90890-01423 Damper rod holder
YM-1423 90890-01423
Use this tool to remove and install the damper rod.
YM-01442, 90890-01442 Fork seal driver
YM-01442 90890-01442
This tool is used when install the fork oil seal.
YU-3112-C, 90890-03112 Yamaha pocket tester
YM-3112-C 90890-03112
Use this tool to inspect the coil resistance,
output voltage and amperage.
YU-8036-B Inductive tachometer
YU-8036-B 90890-03113
90890-03113 Engine tachometer
This tool is needed for observing engine rpm.
YM-91042, 90890-04086 Clutch holding tool
YM-91042 90890-04086
This tool is used to hold the clutch when removing
or installing the clutch boss securing nut.
YM-34487 Dynamic spark tester
YM-34487 90890-06754
90890-06754 Ignition checker
This instrument is necessary for checking the igni-
tion system components.
ACC-QUICK-GS-KT Quick gasket
®ACC-QUICK-GS-KT 90890-85505
90890-85505 YAMAHA Bond No. 1215
This sealant (Bond) is used for crankcase mating
surface, etc.
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1-7
OUTILS SPECIAUX
GEN
INFO
OUTILS SPECIAUX
Les outils spéciaux appropriés sont indispensables pour pouvoir effectuer un assemblage et une mise au
point complets et précis. L’utilisation des outils spéciaux corrects permettra d’éviter les endommagements
dus à l’emploi d’outils impropres et aux techniques improvisées entraînées par ceux-ci. La forme et le
numéro de pièce des outils spéciaux diffèrent selon les pays. Voilà pourquoi il y a parfois deux versions
d’un outil. La liste suivante permet d’éviter toute erreur lors de la commande de pièces.
N.B.:
9Pour les Etats-Unis et le Canada, utilisez les numéros de pièce qui commencent par “YM-”, “YU-” ou
“ACC-”.
9Pour les autres pays utiliser les numéros de pièce qui commencent par “90890-”.
Numéros de pièce Nom et usage de l’outil Illustration
YU-1135-A, 90890-01135 Outil de séparation de carter
Cet outil permet de partager le carter et d’extraire le
vilebrequin de l’une ou l’autre de ses moitiés.YU-1135-A 90890-01135
YM-1189, 90890-01189 Extracteur du volant
Cet outil doit être utilisé pour la dépose du volant
magnétique.YM-1189 90890-01189
YU-1235, 90890-01235 Outil de poignée de rotor
Cet outil est utilisé pour le desserrage ou le serrage du
boulon de fixation de volant magnétique.YU-1235 90890-01235
YU-3097, 90890-01252
YU-1256Comparateur et support
Support du comparateur d’écartement des électrodes de
bougie
Ces outils sont utilisés pour caler l’allumage.YU-3097
YU-125690890-01252
YU-90050, 90890-01274
YU-90050, 90890-01275
YU-90063, 90890-01278Outil de pose du vilebrequin
Pot
Boulon
Adaptateur
Ces outils sont utilisé pour la montage du vilebrequin.
YU-90050
YU-9006390890-01274
90890-01275
90890-01278
YU-1304, 90890-01304 Extracteur d’axe de piston
Cet outil est utilisé pour enlever les axes de piston.YU-1304 90890-01304
YU-24460-01, 90890-01325
YU-33984, 90890-01352Appareil de contrôle de bouchon de radiateur
Adaptateur
Ces outils sont utilisés pour le contrôle du système de
refroidissement.
YU-24460-01
YU-3398490890-01325
90890-01352
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1-12
FUEL AND ENGINE MIXING OIL
GEN
INFO
EC160051
FUEL AND ENGINE MIXING OIL
Mix oil with the gas at the ratio specified below.
Always use fresh, name-brand gasoline, and mix
the oil and gas the day of the race. Do not use
premix that is more than a few hours old.
NOTE:
If knocking or pinging occurs, use a different
brand of gasoline or higher octane grade.
cC
Never mix two types of oil in the same
batch; clotting of the oil could result. If you
wish to change oil types, be sure to drain
the fuel tank and the carburetor float bowl
of old premix prior to filling with the new
type.
Fuel tank capacity:
8.0 L (1.76 Imp gal, 2.11 US gal)
Mixing oil
Recommended oil:
Yamalube “2-R”
(Yamalube racing 2-cycle oil)
Mixing ratio: 30 : 1
If unavailable, use an equivalent
type of oil.
Recommended fuel:
Except for ZA:
Premium unleaded gasoline
only with a research octane
number of 95 or higher.
For ZA:
Premium gasoline
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1-14
STARTING AND BREAK-IN
GEN
INFO
EC194001
BREAK-IN PROCEDURES
1. Before starting the engine, fill the fuel tank
with a break-in oil-fuel mixture as follows.
2. Perform the pre-operation checks on the
machine.
3. Start and warm up the engine. Check the
idle speed, and check the operation of the
controls and the “ENGINE STOP” button.
4. Operate the machine in the lower gears at
moderate throttle openings for five to eight
minutes. Stop and check the spark plug
condition; it will show a rich condition during
break-in.
5. Allow the engine to cool. Restart the engine
and operate the machine as in the step
above for five minutes. Then, very briefly
shift to the higher gears and check full-throt-
tle response. Stop and check the spark
plug.
6. After again allowing the engine to cool,
restart and run the machine for five more
minutes. Full throttle and the higher gears
may be used, but sustained full-throttle
operation should be avoided. Check the
spark plug condition.
7. Allow the engine to cool, remove the top
end, and inspect the piston and cylinder.
Remove any high spots on the piston with
#600 grit wet sandpaper. Clean all compo-
nents and carefully reassemble the top end.
8. Drain the break-in oil-fuel mixture from the
fuel tank and refill with the specified mix.
9. Restart the engine and check the operation
of the machine throughout its entire operat-
ing range. Stop and check the spark plug
condition. Restart the machine and operate
it for about 10 to 15 more minutes. The
machine will now be ready to race.
Mixing oil: Mixing ratio:
Yamalube “2-R” 15:1
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1-18
CLEANING AND STORAGE
GEN
INFO
EC1B2001
STORAGE
If your machine is to be stored for 60 days or
more, some preventive measures must be taken
to avoid deterioration. After cleaning the
machine thoroughly, prepare it for storage as fol-
lows:
1. Drain the fuel tank, fuel lines, and the carbu-
retor float bowl.
2. Remove the spark plug, pour a tablespoon
of SAE 10W-30 motor oil in the spark plug
hole, and reinstall the plug. With the engine
stop switch pushed in, kick the engine over
several times to coat the cylinder walls with
oil.
3. Remove the drive chain, clean it thoroughly
with solvent, and lubricate it. Reinstall the
chain or store it in a plastic bag tied to the
frame.
4. Lubricate all control cables.
5. Block the frame up to raise the wheels off
the ground.
6. Tie a plastic bag over the exhaust pipe out-
let to prevent moisture from entering.
7. If the machine is to be stored in a humid or
salt-air environment, coat all exposed metal
surfaces with a film of light oil. Do not apply
oil to rubber parts or the seat cover.
NOTE:
Make any necessary repairs before the machine
is stored.
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