air filter YAMAHA YZ250LC 2002 Owners Manual

1-1
DESCRIPTION
BESCHREIBUNG
DESCRIZIONE
GEN
INFO
ALLGEMEIN
ANGABEN
BESCHREIBUNG1Kupplungshebel
2Motorstoppknopf „ENGINE STOP“
3Handbremshebel
4Gasdrehgriff
5Kühlerdeckel
6Kraftstofftank-Verschluß
7Kickstarter
8Kraftstofftank
9Kühler
0Kühlmittel-Ablaßschraube
qPrüfschraube (Getriebeölstand)
wFußbremshebel
eVentilverbindung
rKraftstoffhahn
tStarterknopf
yAntriebskette
uLuftfilter
iSchalthebel
oVorderradgabel
HINWEIS:
9Die von Ihnen gekaufte Maschine
könnte etwas von den hier gezeigten
Abbildungen abweichen.
9Anderungen des Designs und der
Technischen Daten ohne vorherge-
hende Bekanntgage vorbehalten.
RENSEIGNEMENTS
GENERAUX
DESCRIPTION1Levier d’embrayage
2Bouton de coupe-circuit de sécurité
“ENGINE STOP”
3Levier de frein avant
4Poignée d’accélérateur
5Bouchon du radiateur
6Bouchon de réservoir à essence
7Kickstarter
8Réservoir de carburant
9Radiateur
0Boulon de vidange du liquide de
refroidissement
qBoulon de contrôle
(niveau d’huile de transmission)
wPédale de frein arrière
eJoint de robinet
rRobinet à essence
tBouton de starter
yChaîne de transmission
uFiltre à air
iPédale de sélecteur
oFourche avant
N.B.:
9La machine que vous avez achetée
diffère peutêtre partiellement de celles
montrées sur ces photos.
9La conception et les caractéristiques
peuvent êtres changées sans préavis.
IC100000
INFORMAZIONI
GENERALI
IC110000
DESCRIZIONE
1Leva di comando della frizione
2Pulsante “ARRESTO MOTORE”
3Leva di comando del freno anteriore
4Manopola dell’acceleratore
5Tappo del radiatore
6Tappo del serbatoio del carburante
7Pedivella della messa in moto
8Serbatoio del carburante
9Radiatore
0Bullone di drenaggio del liquido
refrigerante
qBullone di controllo
(livello dell’olio della trasmissione)
wPedale di comando del freno posteriore
eGiunto della valvola
rRubinetto del carburante
tManopola dell’avviamento
yCatena di trasmissione
uFiltro dell’aria
iPedale del cambio
oForcella anteriore
NOTA:
9Il veicolo acquistato può essere leg-
germente diverso da quelli illustrati
qui sotto.
9Progetti e specifiche sono soggetti a
variazioni senza preavviso.
1
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1-3
IMPORTANT INFORMATION
GEN
INFO
EC130000
IMPORTANT INFORMATION
EC131010
PREPARATION FOR REMOVAL AND DIS
ASSEMBLY
1. Remove all dirt, mud, dust, and foreign
material before removal and disassembly.
When washing the machine with high pres-
sured water, cover the parts as follows.
9Silencer end
9Air filter intake slit
9Water pump housing hole at the bottom
2. Use proper tools and cleaning equipment.
Refer to “SPECIAL TOOLS” section.
3. When disassembling the machine, keep
mated parts together. They include gears,
cylinders, pistons, and other mated parts
that have been “mated” through normal
wear. Mated parts must be reused as an
assembly or replaced.
4. During the machine disassembly, clean all
parts and place them in trays in the order of
disassembly. This will speed up assembly
time and help assure that all parts are cor-
rectly reinstalled.
5. Keep away from fire.
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1-3
INFORMATIONS IMPORTANTES
WICHTIGE INFORMATIONEN
INFORMAZIONI IMPORTANTI
GEN
INFO
WICHTIGE
INFORMATIONEN
VORBEREITUNG FÜR DEN
AUSBAU UND DER DEMONTAGE
1. Schmutz, Schlamm, Staub und
Fremdmaterial von der Außensei-
te entfernen, bevor mit der
Demontage begonnen wird.
Beim Waschen der Maschine mit
Wasser unter hohem Druck sind
die Teile wie folgt abzudecken.
9Ende des Auspufftopfs
9Ansaugschlitz des Luftfilters
9Öffnung im Boden des Was-
serpumpengehäuses
INFORMATIONS
IMPORTANTES
PREPARATION POUR LA DEPO-
SE ET DEMONTAGE
1. Eliminer soigneusement crasse,
boue, poussière et corps étrangers
avant la dépose et le démontage.
Lors du lavage de la moto avec de
l’eau sous haute pression, recou-
vrir les composants suivants.
9Extrémité du silencieux
9Fente d’admission du filtre à air
9Orifice du corps de pompe à eau
dans le bas
IC130000
INFORMAZIONI
IMPORTANTI
IC131010
PREPARAZIONE PER LA RIMO-
ZIONE E LO SMONTAGGIO
1. Togliere tutto lo sporco, il fango,
la polvere e il materiale estraneo
prima della rimozione e dello
smontaggio.
Quando si pulisce il veicolo con
acqua ad alta pressione, coprirne le
parti seguenti.
9Estremità della marmitta di sca-
rico
9Bocchetta del filtro dell’aria
9Apertura dell’alloggiamento
della pompa dell’acqua dal lato
inferiore
4. Lors du démontage de la machine,
nettoyer toutes les pièces et les
mettre dans des plateaux dans
l’ordre du démontage. Ceci dimi-
nuera le temps de remontage et
permettra d’être sûr que toutes les
pièces sont correctement remon-
tées.
5. Tenir éloigné du feu.
4. Während der Demontage der
Maschine sind alle Teile zu reini-
gen und in der Reihenfolge der
Demontage in Ablagen abzule-
gen, um die Montage zu
beschleunigen und richtigen Ein-
bau aller Teile sicherzustellen.
5. Offene Flammen und Funken
entfernt halten.4. Durante lo smontaggio del veico-
lo, pulire tutte le parti e collocarle
in vassoi nell’ordine in cui vengo-
no smontate. Questo sveltirà i
tempi di montaggio e contribuirà
ad assicurare che tutte le parti ven-
gano reinstallate correttamente.
5. Stare lontani dal fuoco. 3. Lors du démontage de la machine,
garder les pièces connexes
ensemble. Ils comprennent les
engrenages, cylindres, pistons et
autres pièces connexes qui se sont
“accouplées” par usure normale.
Les pièces connexes doivent être
réutilisées en un ensemble ou
changées.
3. Wenn die Maschine demontiert
wird, zusammengehörende Teile
gemeinsam ablegen. Sie umfas-
sen Zahnräder, Zylinder und Kol-
ben bzw. ähnliche zusammen-
gehörende Teile, die durch
gegenseitigen Kontakt einge-
schliffen wurden. Zusammen-
gehörige Teile müssen immer
gemeinsam wieder verwendet
oder erneuert werden.3. Quando si smonta il veicolo, tene-
re insieme le parti accoppiate.
Queste comprendono ingranaggi,
cilindri, pistoni e altre parti accop-
piate che sono state “accoppiate”
dalla normale usura. Le parti
accoppiate devono essere riutiliz-
zate come gruppo oppure sostitui-
te. 2. Utiliser les outils et le matériel de
nettoyage correct.
Se reporter à la section “OUTILS
SPECIAUX”.
2. Geeignete Werkzeuge und Reini-
gungseinrichtungen verwenden.
Siehe Abschnitt „SPEZIAL-
WERKZEUGE“.2. Usare utensili e apparecchiature di
pulitura adeguati. Consultare la
sezione “UTENSILI SPECIALI”.
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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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2-1
GENERAL SPECIFICATIONSSPEC
Model name: YZ250LC (EUROPE)
YZ250P1 (USA)
YZ250(P) (CDN, AUS, NZ, ZA)
Model code number: 5NX1 (USA, CDN, ZA)
5NX2 (EUROPE)
5NX4 (AUS, NZ)
Dimensions:USA, ZAAUS, NZ EUROPE CDN
Overall length 2,183 mm←2,182 mm←
(85.9 in) (85.9 in)
Overall width 827 mm←←←
(32.6 in)
Overall height 1,309 mm 1,296 mm 1,302 mm 1,307 mm
(51.5 in) (51.0 in) (51.3 in) (51.5 in)
Seat height 991 mm←990 mm←
(39.0 in) (39.0 in)
Wheelbase 1,481 mm←1,485 mm←
(58.3 in) (58.5 in)
Minimum ground clearance 395 mm←393 mm←
(15.6 in) (15.5 in)
Basic weight:
With oil and full fuel tank 105.0 kg (231 lb)
Engine:
Engine type Liquid cooled 2-stroke, gasoline
Cylinder arrangement Single cylinder, forward inclined
Displacement 249 cm
3(8.76 lmp oz, 8.42 US oz)
Bore ×Stroke 66.4 ×72 mm (2.614 ×2.835 in)
Compression ratio 9.1~10.6 : 1
Starting system Kick starter
Lubrication system: Premix (30 : 1)(Yamalube 2-R)
Oil type or grade (2-Cycle):
Transmission oil Yamalube 4 (10W-30) or SAE 10W-30 type SE
motor oil
Periodic oil change 0.75 L (0.66 Imp qt, 0.79 US qt)
Total amount 0.80 L (0.70 Imp qt, 0.85 US qt)
Coolant capacity (including all routes): 1.20 L (1.06 Imp qt, 1.27 US qt)
Air filter: Wet type element
Fuel:
Type Except for ZA: Premium unleaded gasoline
only with a research octane
number of 95 or higher
For ZA: Premium gasoline
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
EC200000
SPECIFICATIONSEC211000
GENERAL SPECIFICATIONS
2
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2-4
MAINTENANCE SPECIFICATIONSSPEC
Item Standard Limit
Transmission:
Main axle deflection limit…
0.01 mm (0.0004 in)
Drive axle deflection limit…
0.01 mm (0.0004 in)
Shifter:
Shifting type Cam drum and guide bar…
Guide bar bending limit…
0.05 mm (0.0020 in)
Kick starter type: Kick and ratchet type…
Air filter oil grade (oiled filter):Foam-air-filter oil or engine mixing oil…
Carburetor:USA, CDN, ZA,
EUROPE
AUS, NZ
Type/Manufacturer
PWK38S/KEIHIN←…
I.D. mark 5NX1 00 5NX2 10…
Main jet (M.J.) #178 #175…
Main air jet (M.A.J) #200←…
Jet needle-clip position (J.N.) N3EJ-2 N3CW-3…
Main nozzle (N.J.) ø2.9←…
Cutaway (C.A.) #7←…
Pilot jet (P.J.) #50 #52…
Pilot air screw (P.A.S.) 1 1-3/8…
(for reference only)
Valve seat size (V.S.)
ø3.8 mm (0.15 in)←…
Starter jet (G.S.) #85←…
Power jet (P.W.J.) #50←…
Float arm height (F.H.) 5.5~7.5 mm←…
(0.22~030 in)
Reed valve:
Thickness* 0.42 mm (0.017 in)…
Valve stopper height 10.3~10.7 mm (0.406~0.421 in)…
Valve bending limit…
0.2 mm (0.008 in)
Cooling:
Radiator core size:
Width 107.8 mm (4.24 in)…
Height 240 mm (9.45 in)…
Thickness 32 mm (1.26 in)…
Radiator cap opening pressure 95~125 kPa…
(0.95~1.25 kg/cm
2, 13.5~17.8 psi)
Radiator capacity (total) 0.63 L (0.55 Imp qt, 0.67 US qt)…
Water pump:
Type Single-suction centrifugal pump…
5NX-9-30-2 6/7/01 1:57 PM Page 5

2-5
MAINTENANCE SPECIFICATIONSSPEC
Part to be tightened Thread size Q’tyT ightening torqueNm m•kg ft•lb
Spark plug M14 ×1.25 1 20 2.0 14
Cylinder head (nut) M 8 ×1.25 6 25 2.5 18
(stud) M 8 ×1.25 6 13 1.3 9.4
Cylinder (nut) M10 ×1.25 4 35 3.5 25
(stud) M10 ×1.25 4 13 1.3 9.4
Power valve :
Holder M 5 ×0.8 2 6 0.6 4.3
Link rod M 5 ×0.8 2 6 0.6 4.3
Push rod M 5 ×0.8 1 5 0.5 3.6
Thrust plate M 5 ×0.8 1 6 0.6 4.3
Side holder M 5 ×0.8 4 4 0.4 2.9
Link lever M 4 ×0.7 1 4 0.4 2.9
Pulley M 4 ×0.7 2 4 0.4 2.9
Cover M 5 ×0.8 4 4 0.4 2.9
Governor fork M 4 ×0.7 2 5 0.5 3.6
Housing M 5 ×0.8 4 5 0.5 3.6
Impeller M 8 ×1.25 1 14 1.4 10
Water pump housing cover M 6 ×1.0 4 10 1.0 7.2
Coolant drain bolt M 6 ×1.0 1 10 1.0 7.2
Radiator M 6 ×1.0 6 10 1.0 7.2
Radiator panel M 6 ×1.0 2 10 1.0 7.2
Radiator hose clamp M 6 ×1.0 8 1 0.1 0.7
Air filter element M 6 ×1.0 1 2 0.2 1.4
Carburetor joint M 6 ×1.0 5 10 1.0 7.2
Air filter case M 6 ×1.0 4 8 0.8 5.8
Air filter guide clamp M 5 ×0.8 1 1 0.1 0.7
Reed valve M 3 ×0.5 4 1 0.1 0.7
Exhaust pipe (front) M 6 ×1.0 1 14 1.4 10
Exhaust pipe (rear) M 6 ×1.0 1 12 1.2 8.7
Exhaust pipe stay (front) M 8 ×1.25 1 25 2.5 18
Exhaust pipe stay (rear) M 6 ×1.0 1 12 1.2 8.7
Silencer (front) M 6 ×1.0 1 12 1.2 8.7
Silencer (rear) M 6 ×1.0 1 7 0.7 5.1
Fiber (silencer) M 6 ×1.0 2 10 1.0 7.2
Crankcase M 6 ×1.0 11 14 1.4 10
Crankcase cover (left) M 6 ×1.0 5 8 0.8 5.8
Chain cover M 6 ×1.0 2 8 0.8 5.8
Crankcase cover (right) M 6 ×1.0 9 10 1.0 7.2
Bearing plate cover (drive axle left) M 6 ×1.0 2 10 1.0 7.2
Bearing plate cover (main axle right) M 6 ×1.0 2 10 1.0 7.2
Holder M 6 ×1.0 2 10 1.0 7.2
Oil drain bolt M12 ×1.5 1 20 2.0 14
Oil check bolt M 6 ×1.0 1 10 1.0 7.2
Kick starter M 8 ×1.25 1 30 3.0 22
Ratchet wheel stopper M 6 ×1.0 2 10 1.0 7.2
Clutch cover M 6 ×1.0 6 10 1.0 7.2
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INSP
ADJ
3-2
MAINTENANCE INTERVALS
3
Item Remarks
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolantEvery two years
Inspect hoses
OUTSIDE NUTS AND BOLTS Refer to “STARTING
RetightenAND BREAK-IN” section
in the CHAPTER 1.
AIR FILTER
Clean and lubricateUse foam air-filter oil
Replace
FRAME
Clean and inspect
FUEL TANK, COCK
Clean and inspect
BRAKES
Adjust lever position and pedal height
Lubricate pivot point
Check brake disc surface
Check fluid level and leakage
Retighten brake disc bolts, caliper bolts,

master cylinder bolts and union bolts
Replace pads
Replace brake fluidEvery one year
FRONT FORKS
Inspect and adjust
Replace oilSuspension oil “01”
Replace oil seal
FRONT FORK OIL SEAL AND DUST SEAL
Clean and lubeLithium base grease
REAR SHOCK ABSORBER
(After
Inspect and adjustrain ride)
Lube Molybdenum disulfide grease
Retighten
CHAIN GUARD AND ROLLERS
Inspect
SWINGARM
Inspect, lube and retightenMolybdenum disulfide grease
RELAY ARM, CONNECTING ROD
Inspect, lube and retightenMolybdenum disulfide grease
STEERING HEAD
Inspect free play and retighten
Clean and lubeLithium base grease
Replace bearing
TIRE, WHEELS
Inspect air pressure, wheel run-out,

tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
LubricateLithium base grease
THROTTLE, CONTROL CABLE
Check routing and connectionYamaha cable lube or
LubricateSAE 10W-30 motor oil
After
break-
inEvery
raceEvery
thirdEvery
fifthAs re-
quired
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INSP
ADJ
3-11
AIR FILTER CLEANING
3. Install:
9Throttle cable cap
9Cap cover
EC35G040
AIR FILTER CLEANING
NOTE:
Proper air filter maintenance is the biggest key
to preventing premature engine wear and dam-
age.
cC
Never run the engine without the air filter
element in place; this would allow dirt and
dust to enter the engine and cause rapid
wear and possible engine damage.
1. Remove:
9Seat
9Fitting bolt 1
9Washer 2
9Air filter element 3
9Filter guide 4
2. Clean:
9Air filter element
Clean them with solvent.
NOTE:
After cleaning, remove the remaining solvent by
squeezing the element.
cC
Do not twist the element when squeezing
the element.
1 Nm (0.1 m•kg, 0.7 ft•lb)
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3-11
NETTOYAGE DU FILTRE A AIR
REINIGUNG DES LUFTFILTERS
PULITURA DEL FILTRO DELL’ARIA
INSP
ADJ
3. Einbauen:
9Gasseilkappe
9Kappenabdeckung3. Monter:
9Capuchon du câble d’accéléra-
teur
9Couvercle de capuchon
NETTOYAGE DU FILTRE A AIR
N.B.:
Un entretien convenable du filtre à air
est la clé pour éviter l’usure prématurée
et l’endommagement du moteur.
fF
Ne faites jamais tourner le moteur
sans que le filtre à air soit en place;
ceci permettrait l’introduction de
poussiére dans le moteur et causerait
son usure rapide, et même des dom-
mages.
1. Dèposer:
9Selle
9Boulon de fixation 1
9Rondelle 2
9Elément du filtre à air 3
9Guide de filtre 4
2. Nettoyer:
9Elément du filtre à air
Les nettoyer avec du dissolvant.
N.B.:
Une fois l’entretien terminé, éliminer ce
qui reste de solvant en serrant l’élé-
ment.
fF
Ne torder pas l’élément en le esso-
rant.
REINIGUNG DES LUFTFILTERS
HINWEIS:
Richtige Wartung des Luftfilters ist der
wichtigste Punkt, un frühzeitigen Ver-
schleiß und Schaden am Motor zu
vermeiden.
dD
Niemals den Motor bei ausgebau-
tem Luftfilter laufen lassen; anson-
sten würden nämlich Staub und
Schmutz in den Motor eindringen
und schnellen Verschleiß sowie
möglichen Motorschaden verursa-
chen.
1. Ausbauen:
9Sitz
9Befestigungsschraube 1
9Scheibe 2
9Luftfilterelement 3
9Luftfilterführung 4
2. Reinigen:
9Luftfitterelement
Mit einer Waschlösung reini-
gen.
HINWEIS:
Nach dem Reinigen, restliches
Lösungsmittel aus dem Schaumgum-
mi ausdrücken.
dD
Das Filterelement ausdrücken, aber
niemals auswringen.
IC35G040
PULITURA DEL FILTRO
DELL’ARIA
NOTA:
Una corretta manutenzione del filtro
dell’aria è la chiave più importante per
prevenire usura prematura e danni al
motore.
iI
Non fare mai girare il motore senza
l’elemento del filtro dell’aria in posi-
zione; questo permetterebbe allo
sporco e alla polvere di entrare nel
motore e di provocare rapida usura e
possibili danni al motore.
1. Togliere:
9Sella
9Bullone di fissaggio 1
9Rondella 2
9Elemento del filtro dell’aria 3
9Guida del filtro 4
2. Pulire:
9Elemento del filtro dell’aria
Pulirli con solvente.
NOTA:
Dopo la pulitura, togliere il solvente
rimanente comprimendo l’elemento.
iI
Non torcere l’elemento quando lo si
comprime.
3. Installare:
9Calotta del cavo dell’accelerato-
re
9Coperchio della calotta
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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