fuel YAMAHA WR 250F 2008 User Guide

2-1
GENERAL SPECIFICATIONS
SPECIFICATIONS
GENERAL SPECIFICATIONS
Model name:WR250FX (USA, CDN, AUS, NZ)
WR250F (EUROPE, ZA)
Model code number: 5UMH (USA)
5UMK (CDN)
5UML (EUROPE)
5UMM (AUS, NZ, ZA)
Dimensions: USA, CDN, ZA AUS, NZ EUROPE
Overall length 2,165 mm (85.24
in) 2,180 mm (85.83
in)2,190 mm (86.22
in)
Overall width 825 mm (32.48 in)←←
Overall height 1,300 mm (51.18
in) 1,305 mm (51.38
in)←
Seat height 980 mm (38.58 in) 990 mm (38.98 in)←
Wheelbase 1,480 mm (58.27
in) ←
1,485 mm (58.46
in)
Minimum ground clearance 365 mm (14.37 in) 370 mm (14.57 in) 375 mm (14.76 in)
Dry weight: Without oil and fuel 106.0 kg (233.7 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
Starting system Kick and electric starter
Lubrication system: Dry sump
Oil type or grade: Engine oil (For USA and CDN)
Yamalube 4, SAE10W30 or SAE20W40
Yamalube 4-R, SAE10W50
API service SG type or higher,
JASO standard MA
(Except for USA and CDN)
SAE10W30, SAE10W40, SAE15W40,
SAE20W40 or SAE20W50
API service SG type or higher,
JASO standard MA

2-2
GENERAL SPECIFICATIONS
Oil capacity:Engine oilPeriodic oil change 1.1 L (0.97 Imp qt, 1.16 US qt)
With oil filter replacement 1.2 L (1.06 Imp qt, 1.27 US qt)
Total amount 1.4 L (1.23 Imp qt, 1.48 US qt)
Coolant capacity (including all routes): 0.99 L (0.87 Imp qt, 1.05 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 CR9E/NGK (resistance type)
Gap 0.7–0.8 mm (0.028–0.031 in)
Clutch type: Wet, multiple-disc
Transmission: USA, CDN, ZA, AUS, NZEUROPE
Primary reduction system Gear←
Primary reduction ratio 57/17 (3.353)←
Secondary reduction system Chain drive←
Secondary reduction ratio 50/13 (3.846)47/14 (3.357)
Transmission type Constant mesh, 5-speed←
Operation Left foot operation←
Gear ratio: 1st 31/13 (2.385)←
2nd 28/16 (1.750)←
3rd 23/17 (1.353)←
4th 23/21 (1.095)←
5th 17/19 (0.895)←
Chassis: USA, CDN, ZA AUS, NZ EUROPE
Frame type Semi double cra-
dle ←←
Caster angle 27.0 °26.6 °26.5 °
Trail 115 mm (4.53 in) 114 mm (4.49 in) 113 mm (4.45 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)
2

2-15
TIGHTENING TORQUES
△Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
△ Engine guard M6 × 1.0 3 7 0.7 5.1
Regulator M6 × 1.0 2 7 0.7 5.1
△ Pivot shaft and nut M16 × 1.5 1 85 8.5 61
△ 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 38 3.8 27
△ Rear frame (lower) M8 × 1.25 2 32 3.2 23
△ 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 16 1.6 11
Lower drive chain tensioner M8 × 1.25 1 16 1.6 11
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 9 0.9 6.5
△ Fuel cock M6 × 1.0 2 4 0.4 2.9
Seat set bracket 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 bracket M6 × 1.0 2 7 0.7 5.1
Multi-function display M5 × 0.8 2 4 0.4 2.9
Plate 1 and front fork protector M5 × 0.8 2 4 0.4 2.9
Plate 2 and front fork protector —2 0.5 0.05 0.36
Speed sensor lead holder and lower bracket M6 × 1.0 1 13 1.3 9.4
Speed sensor lead holder and clamp M6 × 1.0 1 7 0.7 5.1
Headlight body and headlight unit —2 1 0.1 0.7
△ Headlight M6 × 1.0 2 7 0.7 5.1
Taillight —3 1 0.1 0.7
Taillight lead clamp and rear fender —3 0.5 0.05 0.36
△ Catch tank (upper) M6 × 1.0 1 16 1.6 11
△ Catch tank (lower) M6 × 1.0 1 7 0.7 5.1
Footrest bracket and frame M10 × 1.25 4 55 5.5 40
Sidestand M10 × 1.25 1 25 2.5 18
Part to be tightened
Thread size Q'tyTightening torque
Nm m•kg ft•lb

2-21
CABLE ROUTING DIAGRAM
CABLE ROUTING DIAGRAM
1. Fuel tank breather hose
2. Clamp
3. Diode
4. Hot starter cable
5. Wire harness
6. Hump (frame)
7. Cylinder head breather hose
8. Throttle position sensor lead
9. Neutral switch lead10. Oil hose
11. Clutch cable
12. Starter motor lead
13. Cable guide
14. Negative battery lead
15. AC magneto lead
16. Brake hose
17. Rectifier/regulator lead
18. Carburetor breather hose 19. Carburetor overflow hose
20. Catch tank breather hose

2-22
CABLE ROUTING DIAGRAM
A. Insert the end of the fuel tank breather hose into the hole in
the steering stem.
B. Fasten the throttle cable, hot
starter cable and rectifier/regula-
tor lead onto the frame. Locate
the clamp end facing the lower
side of the hot starter cable and
cut off the tie end.
C. Fasten the diode (at the mark-
ing), throttle cable and hot start-
er cable onto the frame. Locate
the clamp end facing toward the
lower right of the frame and with
the tie end facing downward.
D. Fasten the wire harness, throttle
position sensor lead, starter mo-
tor lead and negative battery
lead onto the frame. Pass the
clamp through the hole in the
stay (air cut-off valve). Locate
the clamp end facing toward the
lower side of the frame and cut
off the tie end.
E. Fasten the throttle position sen-
sor lead onto the frame. Locate
the clamp end facing toward the
lower side of the frame and cut
off the tie end.
F. Pass the carburetor breather hoses, carburetor overflow hose
and catch tank breather hose
between the connecting rod and
cross tube (frame).
G. Fasten the neutral switch lead and oil hose together with the
plastic locking ties and cut off
the tie ends.
H. Fasten the neutral switch lead
and AC magneto lead onto the
frame. Locate the clamp end
facing toward the outside of the
frame and tie end facing toward
the rear of the frame.
I. Pass the clutch cable through
the cable guide.
J. Fasten the starter motor lead, AC magneto lead and neutral
switch lead onto the frame. Lo-
cate the clamp end facing to-
ward the rear of the frame and
cut off the tie end.
K. Fasten the clutch cable, starter motor lead, negative battery
lead, AC magneto lead and neu-
tral switch lead onto the frame.
Locate the clamp end facing to-
ward the rear of the frame and
cut off the tie end.
L. Pass the neutral switch lead and
AC magneto lead on the inside
of the wire harness. M. Fasten the clutch cable, AC
magneto lead and neutral switch
lead onto the frame. Locate the
clamp end near the clutch cable
and cut off the tie end.
N. Pass the clutch cable and wire harness through the cable
guide.
O. Locate the couplers in the frame recess.
P. Pass the carburetor breather hoses, carburetor overflow hose
and catch tank breather hose so
that the hoses do not contact the
rear shock absorber.
Q. Secure the coupler by pushing it
into the hole in the headlight
unit.

3-3
MAINTENANCE INTERVALS
FUEL TANK, COCKClean 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, cali-
per bolts, master cylinder bolts
and union bolts ●●
Replace pads ●
Replace brake fluid ●Every one year
FRONT FORKS Inspect and adjust ●●
Replace oil ●● Suspension oil "S1"
Replace oil seal ●
FRONT FORK OIL SEAL AND
DUST SEAL Clean and lube ●● Lithium base grease
PROTECTOR GUIDE Replace ●
REAR SHOCK ABSORBER Inspect and adjust ●●
Lube ●(After
rain
ride) ●Molybdenum disulfide grease
Retighten ●●
DRIVE CHAIN GUIDE AND
ROLLERS Inspect ●●
SWINGARM Inspect, lube and retighten ●● Molybdenum disulfide grease
RELAY ARM, CONNECTING
ROD Inspect, lube and retighten ●● Molybdenum disulfide grease
SIDESTAND Lubricate ●Lithium base grease
STEERING HEAD Inspect free play and retighten ●●
Clean and lube ●Lithium base grease
Replace bearing ●
Item
After
break- in Every
race
Every third
(or 500 km) Every
fifth (or
1,000 km)
As re-
quired Remarks

3-5
PRE-OPERATION INSPECTION AND MAINTENANCE
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation or practice, make sure the machine is in good operating condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCEItem RoutinePage
Coolant Check that coolant is filled up to the radiator cap. Check the cool-
ing system for leakage. P.3-9 – 10
Fuel Check that a fresh gasoline is filled in the fuel tank. Check the fuel
line for leakage.
P.1-14
Engine oil Check that the oil level is correct. Check the crankcase and oil line
for leakage. P.3-12 – 14
Gear shifter and clutch Check that gears can be shifted correctly in order and that the
clutch operates smoothly. P.3-10
Throttle grip/Housing Check that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.
P.3-10 – 11
Brakes Check the play of front brake and ef fect of front and rear brake. P.3-17 – 20
Drive chain Check drive chain slack and alignment. Check that the drive chain
is lubricated properly. P.3-20 – 21
Wheels Check for excessive wear and ti
re pressure. Check for loose
spokes and have no excessive play. P.3-24
Steering Check that the handlebar can be turned smoothly and have no ex-
cessive play.
P.3-24 – 25
Front forks and rear shock
absorber Check that they operate smoothly and there is no oil leakage.
P.3-21 – 24
Cables (wires) Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or when
the front forks travel up and down. —
Exhaust pipe Check that the exhaust pipe is tightly mount ed and has no cracks. P.3-8 – 9
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-20
Lubrication Check for smooth operation. Lubricate if necessary. P.3-26
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-16
Lead connectors Check that the AC magneto, CDI unit, and ignition coil are con-
nected tightly. P.1-3
Settings Is the machine set suitably for the
condition of the racing course
and weather or by taking into account the results of test runs be-
fore racing? Are inspection and maintenance completely done? P.4-1 – 9

3-6
ENGINE
ENGINE
REMOVING THE SEAT, FUEL TANK AND SIDE COVERS
Order Part name Q'ty Remarks Turn the fuel cock to "OFF".
Disconnect the fuel hose.
1Seat 1
2 Air scoop (left and right) 2
3 Bolt (fuel tank) 2
4 Fuel tank 1
5 Left side cover 1 Open the air filter case cover.
6 Right side cover 1 Refer to removal section.
7 Headlight coupler 1
8 Headlight 1

3-8
ENGINE
REMOVING THE EXHAUST PIPE AND SILENCEROrder Part name Q'ty Remarks Right side cover Refer to "REMOVING THE SEAT, FUEL
TANK AND SIDE COVERS" section.
1 Bolt (silencer clamp) 1 Only loosening.
2 Bolt [silencer (front)] 1
3 Bolt [silencer (rear)] 1
4 Collar 1
5 Silencer 1
6 Silencer clamp 1
7 Nut (exhaust pipe) 2
8 Exhaust pipe 1
9 Gasket 2

3-14
ENGINE
ADJUSTING THE PILOT SCREW
1. Adjust:• Pilot screw "1"
Adjustment steps:
To optimize the fuel flow at a smaller
throttle opening, each machine's pilot
screw has been individually set at the
factory. Before adjusting the pilot
screw, turn it in fully and count the
number of turns. Record this number
as the factory-set number of turns
out.
a. Turn in the pilot screw until it is
lightly seated.
b. Turn out the pilot screw by the factory-set number of turns.
ADJUSTING THE ENGINE IDLING
SPEED
1. Start the engine and thoroughly warm it up.
2. Adjust: • Engine idling speed
Adjustment steps:
a. Turn the throttle stop screw "1"
until the specified engine idling
speed.
Using a digital engine tachometer for
idle speed adjustment, detect the en-
gine idling speed by bringing the
sensing element "c" of the engine ta-
chometer close to the ignition coil "2".
ADJUSTING THE VALVE
CLEARANCE
• The valve clearance should be ad0justed when the engine is cool
to the touch.
• The piston must be at Top Dead Center (T.D.C.) on compression
stroke to check or adjust the valve
clearance.
1. Remove:
•Seat
•Fuel tankRefer to "REMOVING THE SEAT,
FUEL TANK AND SIDE COV-
ERS" section.
2. Drain:
• CoolantRefer to "CHANGING THE
COOLANT" section.
3. Remove: • Right radiatorRefer to "RADIATOR" section in
the CHAPTER 5.
• Carburetor Refer to "CARBU RETOR" section
in the CHAPTER 5.
• Spark plug
• Upper engine bracket
• Cylinder head cover Refer to "CAMSHAFTS" section
in the CHAPTER 5. 4. Remove:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw "2"
• O-ring
5. Check: • Valve clearanceOut of specification →Adjust.
Checking steps:
a. Turn the crankshaft counterclock-
wise with a wrench.
b. Align the T.D.C. mark "a" on the
rotor with the align mark "b" on the
crankcase cover when piston is at
T.D.C. on compression stroke.
In order to be sure t hat the piston is at
Top Dead Center, the punch mark "c"
on the exhaust camshaft and the
punch mark "d" on the intake cam-
shaft must align with the cylinder
head surface, as shown in the illustra-
tion.
Pilot screw (example):
1-1/2 turns out
(For EUROPE)
To increase idle speed →Turn the
throttle stop screw "1" in "a".
To decrease idle speed →Turn the
throttle stop screw "1" out "b".
Engine idling speed:1,750–1,950 r/min
Valve clearance (cold):
Intake valve:0.10–0.15 mm
(0.0039–0.0059 in)
Exhaust valve: 0.17–0.22 mm
(0.0067–0.0087 in)