2003 YAMAHA WR 250F radiator cap

KAPITEL 4
MOTOR
SITZBANK, KRAFTSTOFFTANK
UND SEITENABDECKUNGEN... 4-2
KRÜMMER UND
SCHALLDÄMPFER.................... 4-8
KÜHLER.................................... 4-14
VERGASER............................... 4-22
NOCKENWELLE....................... 4-52
ZYLINDERKOPF....................... 4-74
VENTILE UND
VENTILFEDERN....................... 4-82
ZYLINDER UND KOLBEN...... 4-102
KUPPLUNG............................. 4-118
ÖLFILTEREINSATZ,
WASSERPUMPE UND
RECHTE KURBELWELLENAB-
DECKUNG............................... 4-136
AUSGLEICHSWELLE............. 4-152
ÖLPUMPE............................... 4-160
KICKSTARTER UND
KICKSTARTERWELLE.......... 4-170
AC-MAGNETZÜNDER UND
STARTERKUPPLUNG ........... 4-186
MOTOR DEMONTIEREN........ 4-204
KURBELGEHÄUSE UND
KURBELWELLE..................... 4-218
GETRIEBE, SCHALTWALZE
UND SCHALTGABELN.......... 4-242
KAPITEL 5
FAHRWERK
VORDER- UND HINTERRAD..... 5-2
VORDER- UND
HINTERRADBREMSE.............. 5-24
TELESKOPGABEL................... 5-62
LENKER.................................... 5-92
LENKKOPF............................. 5-104
SCHWINGE............................. 5-120
FEDERBEIN............................ 5-140
CAPITOLO 4
MOTORE
SELLA, SERBATOIO
CARBURANTE E
CARENATURA LATERALE....... 4-3
TUBO DI SCARICO E
SILENZIATORE............................ 4-9
RADIATORE................................ 4-15
CARBURATORE.......................... 4-23
ALBERI A CAMME..................... 4-53
TESTATA DEL CILINDRO....... 4-75
VALVOLE E MOLLE
VALVOLE..................................... 4-83
CILINDRO E PISTONE............ 4-103
FRIZIONE................................... 4-119
ELEMENTO FILTRANTE
DELL’OLIO, POMPA DELL’AC-
QUA E COPERCHIO CARTER
DESTRO ..................................... 4-137
BILANCIERE............................. 4-153
POMPA DELL’OLIO................ 4-161
ALBERO PEDALE E
ALBERO DEL CAMBIO........... 4-171
MAGNETE CA E FRIZIONE
DELLO STARTER..................... 4-187
RIMOZIONE DEL MOTORE... 4-205
CARTER E ALBERO
MOTORE..................................... 4-219
TRASMISSIONE, CAMMA
DEL CAMBIO E FORCELLA
DEL CAMBIO............................. 4-243
CAPITOLO 5
PARTE CICLISTICA
RUOTA ANTERIORE E
RUOTA POSTERIORE................. 5-3
FRENO ANTERIORE E
POSTERIORE............................... 5-25
FORCELLA ANTERIORE......... 5-63
MANUBRIO.................................. 5-93
STERZO....................................... 5-105
FORCELLONE
OSCILLANTE............................. 5-121
AMMORTIZZATORE
POSTERIORE............................. 5-141
CAPÍTULO 4
MOTOR
ASIENTO, DEPÓSITO DE
COMBUSTIBLE Y CUBIERTAS
LATERALES............................... 4-4
TUBO DE ESCAPE Y
SILENCIADOR.......................... 4-10
RADIADOR................................ 4-16
CARBURADOR......................... 4-24
ÁRBOLES DE LEVAS.............. 4-54
CULATA.................................... 4-76
VÁLVULAS Y MUELLES DE
VÁLVULA.................................. 4-84
CILINDRO Y PISTÓN.............. 4-104
EMBRAGUE............................ 4-120
ELEMENTO DEL FILTRO DE
ACEITE, BOMBA DE AGUA Y
CUBIERTA DEL CÁRTER
DERECHA............................... 4-138
COMPENSADOR.................... 4-154
BOMBA DE ACEITE............... 4-162
EJE DEL PEDAL Y EJE DE
CAMBIOS................................ 4-172
MAGNETO DE CA Y
EMBRAGUE DEL
ARRANCADOR ...................... 4-188
EXTRACCIÓN DEL MOTOR... 4-206
CÁRTER Y CIGÜEÑAL........... 4-220
CAJA DE CAMBIOS,
LEVA DE CAMBIOS Y
HORQUILLA DE CAMBIOS.... 4-244
CAPÍTULO 5
CHASIS
RUEDA DELANTERA Y
RUEDA TRASERA...................... 5-4
FRENO DELANTERO Y
FRENO TRASERO.................... 5-26
HORQUILLA DELANTERA...... 5-64
MANILLAR................................ 5-94
DIRECCIÓN............................. 5-106
PALANCA OSCILANTE.......... 5-122
AMORTIGUADOR
TRASERO............................... 5-142

1 - 1
GEN
INFODESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1Clutch lever
2Hot starter lever
3Engine stop switch
4Trip meter
5Main switch
6Light switch
7Start switch
8Front brake lever
9Throttle grip
0Radiator cap
AFuel tank cap
BTaillight
CKickstarter crank
DFuel tank
EHeadlight
FRadiator
GCoolant drain bolt
HRear brake pedal
IValve joint
JFuel cock
KCold starter knob
LAir cleaner
MDrive chain
NShift pedal
OOil dipstick
PFront fork
NOTE:The machine you have purchased may differ slightly
from those shown in the following.
Designs and specifications are subject to change with-
out notice.
B
CDE
F
G H
1234
5
6
7
8
9
0 A
IJ
K
L
M N
O P
RENSEIGNEMENTS GENERAUX
DESCRIPTION
1Levier d’embrayage
2Levier de démarreur à chaud
3Coupe-circuit du moteur
4Compteur de vitesse
5Commutateur principal
6Interrupteur lumiêres
7Commutateur de démarrage
8Levier de frein avant
9Poignée des gaz
0Bouchon de radiateur
ABouchon de réservoir de carburant
BLampe arrière
CPedale de kick
DRéservoir de carburant
EPhare
FRadiateur
GBoulon de vidange du liquide de refroidissement
HPédale de frein arrière
IClapet de durit de mise a liair
JRobinet de carburant
KBouton de démarrage à froid
LFiltre à air
MChaîne de transmission
NPédale de sélecteur
OJauge de niveau d’huile
PFourche avant
N.B.:
Votre machine diffère peut-être partiellement de celle mon-
trée sur ces photos.
La conception et les caractéristiques peuvent êtres changées
sans préavis.
DESCRIPTION

1 - 11
GEN
INFO
SPECIAL TOOLS
SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the correct special tool
will help prevent damage caused by the use of improper tools or improvised techniques. The shape and part number used
for the special tool differ by country, so two types are provided. Refer to the list provided to avoid errors when placing an
order.
NOTE:For U.S.A. and Canada, use part number starting with “YM-”, “YU-” or “ACC-”.
For others, use part number starting with “90890-”.
Part number Tool name/How to use Illustration
YU-1135-A, 90890-01135 Crankcase separating tool
These tool is used to remove the crankshaft from
either case.
YU-3097, 90890-01252
YU-1256Dial gauge and stand
Stand
These tools are used to check each part for runout or
bent.
YU-90050, 90890-01274
YU-90050, 90890-01275
YM-91044, 90890-04081
YU-90063, 90890-01278Crankshaft installing tool
Crankshaft installing pot
Crankshaft installing bolt
Spacer (crankshaft installer)
Adapter (M12)
These tools are used to install the crankshaft.
YU-1304, 90890-01304 Piston pin puller set
This tool is used to remove the piston pin.
YU-24460-01, 90890-01325
YU-33984, 90890-01352Radiator cap tester
Radiator cap tester adapter
These tools are used for checking the cooling
system.
YU-33975, 90890-01403 Steering nut wrench
This tool is used when tighten the steering ring nut to
specification.
YM-1423, 90890-01423 Damper rod holder
Use this tool to remove and install the damper rod.
YM-01442, 90890-01442 Fork seal driver
This tool is used when install the fork oil seal.

MAINTENANCE SPECIFICATIONS
2 - 9
SPEC
Lubrication system:
Oil filter type Paper type ----
Oil pump type Trochoid type ----
Tip clearance 0.12 mm or less
(0.0047 in or less)0.20 mm
(0.008 in)
Side clearance 0.09 ~ 0.17 mm
(0.0035 ~ 0.0067 in)0.24 mm
(0.009 in)
Housing and rotor clearance 0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)0.17 mm
(0.0067 in)
Cooling:
Radiator core size
Width 117.8 mm (4.6 in) ----
Height 220 mm (8.7 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure 110 kPa (1.1 kg/cm
2, 15.6 psi) ----
Radiator capacity (total) 0.6 L (0.53 Imp qt, 0.63 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit

MAINTENANCE SPECIFICATIONS
2 - 10
SPEC
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Spark plug M10S × 1.0 1 13 1.3 9.4
Camshaft cap M6 × 1.0 10 10 1.0 7.2
Cylinder head blind plug screw M12 × 1.0 1 37 3.7 27
Cylinder head (stud bolt) M6 × 1.0 2 7 0.7 5.1
(stud bolt) M8 × 1.25 1 15 1.5 11
(bolt) M9 × 1.25 4 38 3.8 27
(nut) M6 × 1.0 2 10 1.0 7.2
Cylinder head cover M6 × 1.0 2 10 1.0 7.2
Cylinder M6 × 1.0 1 10 1.0 7.2
Balancer weight M6 × 1.0 2 10 1.0 7.2
Balancer shaft driven gear M14 × 1.0 1 50 5.0 36
Timing chain guide (intake side) M6 × 1.0 2 10 1.0 7.2
Timing chain tensioner M6 × 1.0 2 10 1.0 7.2
Timing chain tensioner cap bolt M6 × 1.0 1 7 0.7 5.1
Impeller M8 × 1.25 1 14 1.4 10
Radiator hose clamp M6 × 1.0 8 2 0.2 1.4
Coolant drain bolt M6 × 1.0 1 10 1.0 7.2
Water pump housing M6 × 1.0 4 10 1.0 7.2
Radiator M6 × 1.0 6 10 1.0 7.2
Radiator guard M6 × 1.0 2 10 1.0 7.2
Radiator pipe M6 × 1.0 1 10 1.0 7.2
Oil pump cover M4 × 0.7 1 2 0.2 1.4
Oil pump M6 × 1.0 3 10 1.0 7.2
Oil filter element drain bolt M6 × 1.0 1 10 1.0 7.2
Oil filter element cover M6 × 1.0 2 10 1.0 7.2
Oil strainer M6 × 1.0 2 10 1.0 7.2
Oil delivery pipe 1 (M10) M10 × 1.25 1 20 2.0 14
(M8) M8 × 1.25 2 18 1.8 13
Oil hose M6 × 1.0 2 10 1.0 7.2
Oil hose clamp—220.21.4
Oil strainer and frame M14 × 1.5 1 70 7.0 50
Carburetor joint clamp M4 × 0.7 2 3 0.3 2.2
Air filter joint clamp M6 × 1.0 1 3 0.3 2.2
Throttle cable (pull) M6 × 1.0 1 4 0.4 2.9
Throttle cable (return) M12 × 1.0 1 11 1.1 8.0
Throttle cable cover M5 × 0.8 2 4 0.4 2.9
Hot starter plunger M12 × 1.0 1 2 0.2 1.4
Air filter case M6 × 1.0 2 8 0.8 5.8
Air filter joint and air filter case M5 × 0.8 1 4 0.4 2.9
Exhaust pipe (nut) M8 × 1.25 1 13 1.3 9.4
(bolt) M8 × 1.25 1 24 2.4 17
Exhaust pipe protector M6 × 1.0 3 10 1.0 7.2

SPECIFICHE DI MANUTENZIONESPEC
2 - 66 Sistema di lubrificazione:
Tipo di filtro Tipo carta ----
Tipo di pompa dell’olio Tipo trocoidale ----
Gioco della punta 0,12 mm o inferiore
(0,0047 in o inferiore)0,20 mm
(0,008 in)
Gioco laterale 0,09 ~ 0,17 mm (0,0035 ~ 0,0067 in) 0,24 mm
(0,009 in)
Gioco alloggiamento e rotore 0,03 ~ 0,10 mm (0,0012 ~ 0,0039 in) 0,17 mm
(0,0067 in)
Raffreddamento:
Dimensioni massa radiante
Larghezza 117,8 mm (4,6 in) ----
Altezza 220 mm (8,7 in) ----
Spessore 32 mm (1,26 in) ----
Pressione di apertura tappo radiatore 110 kPa (1,1 kg/cm
2, 15,6 psi) ----
Capacità del radiatore (totale) 0,6 L (0,53 Imp qt, 0,63 US qt) ----
Pompa dell’acqua
Tipo Pompa centrifuga ad aspirazione
singola---- Elemento Standard Limite

SPECIFICHE DI MANUTENZIONESPEC
2 - 67 Elemento da serrareDimensioni
della filettaturaQuantitàCoppia di serraggio
Nm m·kg ft·lb
Candela d’accensione M10S × 1,0 1 13 1,3 9,4
Cappello dell’albero a camme M6 × 1,0 10 10 1,0 7,2
Tappo a vite testata del cilindro M12 × 1,0 1 37 3,7 27
Testata del cilindro (prigioniero) M6 × 1,0 2 7 0,7 5,1
(prigioniero) M8 × 1,25 1 15 1,5 11
(bullone) M9 × 1,25 4 38 3,8 27
(dado) M6 × 1,0 2 10 1,0 7,2
Coperchio testata del cilindro M6 × 1,0 2 10 1,0 7,2
Cilindro M6 × 1,0 1 10 1,0 7,2
Peso bilanciere M6 × 1,0 2 10 1,0 7,2
Ingranaggio condotto dell’albero di equilibratura M14 × 1,0 1 50 5,0 36
Guida catena di distribuzione (lato aspirazione) M6 × 1,0 2 10 1,0 7,2
Tenditore catena di distribuzione M6 × 1,0 2 10 1,0 7,2
Vite senza dado del tenditore della catena di
distribuzioneM6 × 1,0 1 7 0,7 5,1
Rotore M8 × 1,25 1 14 1,4 10
Tubo flessibile radiatore M6 × 1,0 8 2 0,2 1,4
Bullone di scarico del refrigerante M6 × 1,0 1 10 1,0 7,2
Alloggiamento della pompa dell’acqua M6 × 1,0 4 10 1,0 7,2
Radiatore M6 × 1,0 6 10 1,0 7,2
Riparo del radiatore M6 × 1,0 2 10 1,0 7,2
Tubazione del radiatore M6 × 1,0 1 10 1,0 7,2
Coperchio pompa dell’olio M4 × 0,7 1 2 0,2 1,4
Pompa dell’olio M6 × 1,0 3 10 1,0 7,2
Bullone di scarico elemento filtro dell’olio M6 × 1,0 1 10 1,0 7,2
Coperchio filtro dell’olio M6 × 1,0 2 10 1,0 7,2
Filtro olio M6 × 1,0 2 10 1,0 7,2
Tubazione alimentazione olio 1 (M10) M10 × 1,25 1 20 2,0 14
(M8) M8 × 1,25 2 18 1,8 13
Tubo flessibile dell’olio M6 × 1,0 3 10 1,0 7,2
Fascetta fermatubo dell’olio—220,21,4
Filtro dell’olio e telaio M14 × 1,5 1 70 7,0 50
Fascetta giunto carburatore M4 × 0,7 2 3 0,3 2,2
Fascetta giunto filtro dell’aria M6 × 1,0 1 3 0,3 2,2
Cavo acceleratore (tiraggio) M6 × 1,0 1 4 0,4 2,9
Cavo acceleratore (rilascio) M12 × 1,0 1 11 1,1 8,0
Coperchio cavo acceleratore M5 × 0,8 1 4 0,4 2,9
Stantuffo dell’avviamento a caldo M12 × 1,0 1 2 0,2 1,4
Scatola del filtro dell’aria M6 × 1,0 2 8 0,8 5,8
Giunto filtro dell’olio e contenitore filtro dell’aria M5 × 0,8 1 4 0,4 2,9
Tubo di scarico (dado) M8 × 1,25 1 13 1,3 9,4
(bullone) M8 × 1,25 1 24 2,4 17
Protezione tubo di scarico M6 × 1,0 3 10 1,0 7,2

SPEC
2 - 97
CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1Fuel tank breather hose
2Oil tank breather hose
3Clamp
4Diode
5Wire harness
6Hot starter cable
7Throttle position sensor lead
8Neutral switch lead
9Oil hose
0Hose guideAAC magneto lead
BCylinder head breather hose
CStarter motor lead
DClutch cable
ERadiator hose 1
FRadiator pipe (radiator hose 4)
GCable guide
HNegative battery lead
ILight switch lead
JBrake hoseKCarburetor breather hose
LCarburetor overflow hose
MCoolant reservoir breather hose
ÈInsert the fuel tank breather hose into
the hole in the steering stem cap.
ÉPass the oil tank breather hose on the
outside of the AC magneto lead, neu-
tral switch lead, light switch lead, wire
harness, starter motor lead, negative
battery lead and cylinder head breather
hose.