engine YAMAHA WR 250F 2006 Owner's Manual

1 - 65
GEN
INFO
EC1B0000
CLEANING AND
STORAGE
EC1B1000CLEANING
Frequent cleaning of your machine
will enhance its appearance, main-
tain good overall performance, and
extend the life of many components.
1. Before washing the machine,
block off the end of the exhaust
pipe to prevent water from enter-
ing. 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 garden hose; use only
enough pressure to do the job.
CAUTION:
Excessive hose pressure may
cause water seepage and contami-
nation of wheel bearings, front
forks, brakes and transmission
seals. Many expensive repair bills
have resulted from improper high
pressure detergent applications
such as those available in coin-
operated car washers.
4. After the majority of the dirt has
been hosed off, wash all sur-
faces with warm water and a
mild detergent. Use an old tooth-
brush to clean hard-to-reach
places.
5. Rinse the machine off immedi-
ately 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 uphol-
stery cleaner to keep the cover
pliable and glossy.
8. Automotive wax may be applied
to all painted or chromed sur-
faces. Avoid combination
cleaner-waxes, as they may con-
tain abrasives.
9. After completing the above, start
the engine and allow it to idle for
several minutes.
NETTOYAGE ET
REMISAGE
NETTOYAGE
Un nettoyage fréquent de la moto préser-
vera son apparence, maintiendra ses bon-
nes performances et augmentera la durée
de vie de nombre de ses composants.
1. Avant de nettoyer la moto, couvrir
la sortie du tuyau d’échappement
pour éviter toute pénétration d’eau.
Un sachet en plastique retenu par un
élastique fera l’affaire.
2. Si le moteur est fortement encrassé,
appliquer un peu de dégraissant à
l’aide d’un pinceau. Eviter tout con-
tact avec la chaîne, les pignons ou
les axes de roue.
3. Rincer la saleté et le dégraissant au
tuyau d’arrosage, en utilisant juste
la pression nécessaire.
ATTENTION:
Une pression excessive risque de cau-
ser des infiltrations d’eau dans les
roulements des roues, la fourche
avant, les freins et les joints de la
transmission. L’emploi abusif de
détergents sous forte pression, tels que
ceux utilisés dans les portiques de
lavage automatique, est nuisible à la
moto et peut entraîner des réparations
onéreuses.
4. Après avoir éliminé le plus gros de
la saleté au tuyau d’arrosage, laver
toutes les surfaces à l’eau chaude
savonneuse (employer un détergent
doux). Une vieille brosse à dents
convient parfaitement pour nettoyer
les parties difficiles d’accès.
5. Rincer immédiatement la moto à
l’eau claire et sécher toutes les sur-
faces à l’aide d’une peau de cha-
mois, d’une serviette ou d’un
chiffon doux absorbant.
6. Sécher immédiatement la chaîne à
l’aide d’une serviette en papier et la
graisser afin de la protéger contre la
rouille.
7. Nettoyer la selle à l’aide d’un pro-
duit de nettoyage pour similicuir
afin de conserver intacts la sou-
plesse et le lustre de la housse.
8. Une cire pour carrosserie peut être
utilisée pour toutes les surfaces
peintes et chromées. Ne pas
employer de cires détergentes car
elles contiennent souvent des abra-
sifs.
9. Lorsque le nettoyage est terminé,
mettre le moteur en marche et le
laisser tourner au ralenti pendant
plusieurs minutes.
CLEANING AND STORAGE
NETTOYAGE ET REMISAGE

1 - 67
GEN
INFO
EC1B2001STORAGE
If your machine is to be stored for 60
days or more, some preventive mea-
sures must be taken to avoid deterio-
ration. After cleaning the machine
thoroughly, prepare it for storage as
follows:
1. Drain the fuel tank, fuel lines,
and the carburetor 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 outlet 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.REMISAGE
Si la moto doit être remisée pour 60
jours ou plus, il convient de prendre cer-
taines précautions pour éviter tout
endommagement. Après un nettoyage
complet de la moto, la préparer comme
suit pour le remisage:
1. Vidanger le réservoir de carburant,
le circuit de carburant et la cuve à
niveau constant du carburateur.
2. Déposer la bougie, verser une
cuillère à soupe d’huile moteur SAE
10W-30 dans le trou de bougie et
replacer la bougie. Enfoncer le
coupe-circuit du moteur et lancer
quelques fois le moteur à l’aide de
la pédale de kick afin de répartir
l’huile sur les parois du cylindre.
3. Déposer la chaîne de transmission,
la nettoyer soigneusement à l’aide
d’un solvant puis la graisser.
Remettre en place la chaîne ou la
conserver dans un sachet en plasti-
que (attaché au cadre pour éviter de
l’égarer).
4. Lubrifier tous les câbles de com-
mande.
5. Placer un support sous le cadre afin
de surélever les deux roues.
6. Couvrir la sortie du tuyau d’échap-
pement d’un sachet en plastique
pour empêcher la pénétration
d’humidité.
7. Si la moto doit être remisée dans un
lieu très humide ou exposé à l’air
marin, enduire toutes les surfaces
métalliques extérieures d’une fine
couche d’huile. Ne pas enduire
d’huile les parties en caoutchouc et
la housse de selle.
N.B.:
Effectuer toutes les réparations nécessai-
res avant de remiser la moto.
CLEANING AND STORAGE
NETTOYAGE ET REMISAGE

GENERAL SPECIFICATIONS
2 - 1
SPEC
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: WR250FV (USA, CDN, AUS, NZ)
WR250F (EUROPE, ZA)
Model code number: 5UMB (USA)
5UMC (EUROPE)
5UMD (CDN, AUS, NZ, ZA)
Dimensions: USA, ZA, CDN EUROPE, AUS, NZ
Overall length 2,190 mm (86.22 in) 2,180 mm (85.83 in)
Overall width 830 mm (32.68 in)←
Overall height 1,290 mm (50.79 in) 1,295 mm (50.98 in)
Seat height 985 mm (38.78 in) 990 mm (38.98 in)
Wheelbase 1,470 mm (57.87 in)←
Minimum ground clearance 370 mm (14.57 in) 375 mm (14.76 in)
Dry weight:
Without oil and fuel 106.5 kg (234.8 lb)
Engine:
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Single cylinder, forward inclined
Displacement 249 cm
3 (8.76 Imp oz, 8.42 US oz)
Bore × stroke 77.0 × 53.6 mm (3.03 × 2.11 in)
Compression ratio 12.5 : 1
Kick and electric starter
Starting system
Lubrication system: Dry sump
Oil type or grade:
Engine oil (For USA and CDN)
At 5 °C (40 °F) or higher È
Yamalube 4 (20W-40) or SAE 20W-40 type
SG motor oil
(Non-Friction modified)
At 15 °C (60 °F) or lower É
Yamalube 4 (10W-30) or SAE 10W-30 type
SG motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
(Non-Friction modified)
(Except for USA and CDN)
API “SG” or higher grade
-20
-4-10
140
3010
5020
6830
8640 50
104
122˚CTemp.
˚F
10W-30
10W-40
20W-40
20W-50
15W-40
2

GENERAL SPECIFICATIONS
2 - 2
SPEC
Oil capacity:
Engine oil
Periodic oil change 1.2 L (1.06 Imp qt, 1.27 US qt)
With oil filter replacement 1.3 L (1.14 Imp qt, 1.37 US qt)
Total amount 1.4 L (1.23 Imp qt, 1.48 US qt)
Coolant capacity (including all routes): 1.26 L (1.11 Imp qt, 1.33 US qt)
Air filter: Wet type element
Fuel:
Type Premium unleaded gasoline only with a
research octane number of 95 or higher.
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
Reserve 1.1 L (0.24 Imp gal, 0.29 US gal)
Carburetor:
Type FCR-MX37
Manufacturer KEIHIN
Spark plug:
Type/manufacturer CR8E/NGK (resistance type)
Gap 0.7 ~ 0.8 mm (0.028 ~ 0.031 in)
Clutch type: Wet, multiple-disc
Transmission:
Primary reduction system Gear
Primary reduction ratio 57/17 (3.353)
Secondary reduction system Chain drive
Secondary reduction ratio 52/13 (4.000)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 31/13 (2.385)
2nd 28/16 (1.750)
3rd 28/21 (1.333)
4th 25/24 (1.042)
5th 22/27 (0.815)
Chassis: USA, ZA, CDN EUROPE, AUS, NZ
Frame type Semi double cradle←
Caster angle 27.5°27.1°
Trail 121 mm (4.76 in) 117 mm (4.61 in)
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN and ZA)
90/90-21 54R (For EUROPE, AUS and NZ)
Size (rear) 100/100-18 59M (For USA, CDN and ZA)
130/90-18 69R (For EUROPE, AUS and NZ)
Tire pressure (front and rear) 100 kPa (1.0 kgf/cm
2, 15 psi)
1
2
3
4
5
6
7

MAINTENANCE SPECIFICATIONS
2 - 4
SPEC
MAINTENANCE SPECIFICATIONS
ENGINE
Item Standard Limit
Cylinder head:
Warp limit ---- 0.05 mm
(0.002 in)
Cylinder:
Bore size 77.00 ~ 77.01 mm
(3.0315 ~ 3.0319 in)----
Out of round limit ---- 0.05 mm
(0.002 in)
Camshaft:
Drive method Chain drive (Left) ----
Camshaft cap inside diameter 22.000 ~ 22.021 mm
(0.8661 ~ 0.8670 in)----
Camshaft outside diameter 21.959 ~ 21.972 mm
(0.8645 ~ 0.8650 in)----
Shaft-to-cap clearance 0.028 ~ 0.062 mm
(0.0011 ~ 0.0024 in)0.08 mm
(0.003 in)
Cam dimensions
Intake“A”30.296 ~ 30.346 mm
(1.1923 ~ 1.1947 in)30.196 mm
(1.1888 in)
“B”22.45 ~ 22.55 mm
(0.8839 ~ 0.8878 in)22.35 mm
(0.8799 in)
Exhaust“A”30.399 ~ 30.499 mm
(1.1968 ~ 1.2007 in)30.299 mm
(1.1929 in)
“B”22.45 ~ 22.55 mm
(0.8839 ~ 0.8878 in)22.35 mm
(0.8799 in)
Camshaft runout limit ---- 0.03 mm
(0.0012 in)
A
B

MAINTENANCE SPECIFICATIONS
2 - 8
SPEC
Clutch:
Friction plate thickness 2.9 ~ 3.1 mm (0.114 ~ 0.122 in) 2.7 mm
(0.106 in)
Quantity 9 ----
Clutch plate thickness 1.1 ~ 1.3 mm (0.043 ~ 0.051 in) ----
Quantity 8 ----
Warp limit ---- 0.1 mm
(0.004 in)
Clutch spring free length 37.0 mm (1.46 in) 36.0 mm
(1.42 in)
Quantity 5 ----
Clutch housing thrust clearance 0.10 ~ 0.35 mm
(0.0039 ~ 0.0138 in)----
Clutch housing radial clearance 0.010 ~ 0.044 mm
(0.0004 ~ 0.0017 in)----
Clutch release method Inner push, cam push ----
Shifter:
Shifter type Cam drum and guide bar ----
Guide bar bending limit ---- 0.05 mm
(0.002 in)
Kickstarter:
Type Kick and ratchet type ----
Carburetor:
Type/manufacturer FCR-MX37/KEIHIN
I. D. mark 5UMB B0
Main jet (M.J) #168
Main air jet (M.A.J) #115
Jet needle (J.N) NGSU
Cutaway (C.A) 1.5
Pilot jet (P.J) #42
Pilot air jet (P.A.J) #70
Pilot outlet (P.O)ø0.9
Bypass (B.P)ø1.0
Valve seat size (V.S)ø3.8
Starter jet (G.S) #68
Leak jet (Acc.P) #70
Float height (F.H) 8 mm (0.31 in)
Engine idle speed 1,750 ~ 1,950 r/min
Intake vacuum 31.3 ~ 36.7 kPa
(235 ~ 275 mmHg,
9.25 ~ 10.83 inHg)
Hot starter lever free play 3 ~ 6 mm
(0.12 ~ 0.24 in) Item Standard Limit

MAINTENANCE SPECIFICATIONS
2 - 15
SPEC
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Nipple (spoke)—72 3 0.3 2.2
Rear wheel sprocket M8 × 1.25 6 50 5.0 36
Rear brake disc cover M6 × 1.0 2 7 0.7 5.1
Rear brake caliper protector M6 × 1.0 2 7 0.7 5.1
Drive chain puller adjust bolt and locknut M8 × 1.25 2 16 1.6 11
Engine mounting:
Engine and engine bracket (front) M10 × 1.25 1 69 6.9 50
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Engine bracket and frame M8 × 1.25 6 34 3.4 24
Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
Lower engine guard M6 × 1.0 3 10 1.0 7.2
Left engine guard M8 × 1.25 2 23 2.3 17
Right engine guard M8 × 1.25 2 23 2.3 17
Regulator M6 × 1.0 2 7 0.7 5.1
Pivot shaft and nut M16 × 1.5 1 80 8.0 58
Relay arm and swingarm M14 × 1.5 1 70 7.0 50
Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
Connecting rod and frame M14 × 1.5 1 80 8.0 58
Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
Rear frame (upper) M8 × 1.25 1 32 3.2 23
Rear frame (lower) M8 × 1.25 2 29 2.9 21
Swingarm and brake hose holder M5 × 0.8 4 2 0.2 1.4
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Upper drive chain tensioner M8 × 1.25 1 19 1.9 13
Lower drive chain tensioner M8 × 1.25 1 20 2.0 14
Drive chain support M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank M6 × 1.0 2 10 1.0 7.2
Fuel cock M6 × 1.0 2 6 0.6 4.3
Seat set bracket and fuel tank M6 × 1.0 1 7 0.7 5.1
Hooking screw (fitting band) and fuel tank M6 × 1.0 1 7 0.7 5.1
Fuel tank bracket and fuel tank M6 × 1.0 4 7 0.7 5.1
Air scoop and fuel tank M6 × 1.0 6 7 0.7 5.1
Air scoop and radiator guard (lower) M6 × 1.0 2 6 0.6 4.3
Front fender M6 × 1.0 4 7 0.7 5.1
Rear fender (front) M6 × 1.0 2 7 0.7 5.1
Rear fender (rear) M6 × 1.0 2 11 1.1 8.0
Side cover M6 × 1.0 2 7 0.7 5.1
Seat M8 × 1.25 2 23 2.3 17
Multi-function display bracket and upper
bracketM6 × 1.0 2 7 0.7 5.1
Multi-function display M5 × 0.8 2 4 0.4 2.9

2 - 19
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
SPEC
EC220001
GENERAL TORQUE SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A: Distance between flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
A
(Nut)B
(Bolt)TORQUE
SPECIFICATION
Nm mkg ftlb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3 meter
10-2 meterLength
Length
kg kilogram 10
3 gram Weight
N Newton 1 kg
× m/sec
2 Force
Nm
m  kgNewton meter
Meter kilogramN
× m
m
× kgTorque
Torque
Pa Pascal N/m
2Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3 Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute—Engine speed

SPEC
2 - 111
CABLE ROUTING DIAGRAM
1Throttle cable
2Clamp
3Brake hose
4Hot starter cable
5Clutch cable
6Hose guide
7Speed sensor lead
8Main switch lead
9Main switch
0Multi-function display
AStart switch lead
BClutch switch lead
CEngine stop switch lead
DMulti-function display leadÈFasten the start switch lead to the han-
dlebar with the plastic bands.
ÉFasten the engine stop switch lead and
clutch switch lead to the handlebar with
the plastic bands.
ÊPass the brake hose through the hose
guides.
ËSecure the coupler by inserting it into
the multi-function display bracket.
ÌPass the main switch lead above the
multi-function display bracket.
ÍPass the throttle cables, clutch cable
and hot starter cable between the upper
bracket and multi-function display
bracket.ÎPass the multi-function display lead and
speed sensor lead between the multi-
function display and multi-function dis-
play bracket.
ÏSecure the coupler by pushing it into
the hole in the multi-function display
bracket.
ÐFasten the clutch switch lead and
engine stop switch lead to the multi-
function display bracket and cut off the
tie end. Fasten them at a location
where the tie end does not contact the
multi-function display.
ÑSecure the wire harness clip by pushing
it into the hole in the multi-function dis-
play bracket on the inside.
4
5
Î
Ê Ó
A
B
F-FE-E
CD
A
D
7 7
2
Ò Ë
A
12
È32
É
6
Ê
6
8
Ì0
9
ËÑ C
BÏ
2
Ð 8
8
1Í
4
5
4
5B2
C
DC BB A
F F
EE
EE
Ë
2

3 - 1
INSP
ADJ
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind that such factors as
weather, terrain, geographical location, and individual usage will alter the required maintenance and lubrication intervals. If
you are a doubt as to what intervals to follow in maintaining and lubricating your machine, consult your Yamaha dealer.
ItemAfter
break-inEvery
race
Every third
(or
500 km)Every fifth
(or
1,000 km)As
requiredRemarks
ENGINE OIL
Replace
Inspect
VALVES
Check the valve clearances The engine must be cold.
Check the valve seats and
valve stems for wear. Inspect
Replace
VALVE SPRINGS
InspectCheck the free length and
the tilt.
Replace
VALVE LIFTERS
InspectCheck for scratches and
wear.
Replace
CAMSHAFTSInspect the camshaft
surface.
Inspect the decompression
system. Inspect
Replace
TIMING CHAIN SPROCKETS, TIMING
CHAIN
InspectCheck for wear on the teeth
and for damage.
Replace
PISTON
InspectInspect crack
Inspect carbon deposits and
eliminate them. Clean
Replace
PISTON RING
InspectCheck ring end gap
Replace
PISTON PIN
Inspect
Replace
CYLINDER HEADInspect carbon deposits and
eliminate them.
Change gasket Inspect and clean
CYLINDER
Inspect and clean Inspect score marks
Inspect wear
Replace
CLUTCH
Inspect and adjust Inspect housing, friction
plate, clutch plate and spring
Replace
TRANSMISSION
Inspect
Replace bearing
SHIFT FORK, SHIFT CAM, GUIDE BAR
InspectInspect wear