2003 YAMAHA WR 250F maintenance

MAINTENANCE SPECIFICATIONS
2 - 7
SPEC
Piston pin bore inside diameter 16.002 ~ 16.013 mm
(0.6300 ~ 0.6304 in)16.043 mm
(0.6316 in)
Piston pin outside diameter 15.991 ~ 16.000 mm
(0.6296 ~ 0.6299 in)15.971 mm
(0.6288 in)
Piston rings:
Top ring:
Type Barrel ----
Dimensions (B × T) 0.90 × 2.75 mm (0.04 × 0.11 in) ----
End gap (installed) 0.15 ~ 0.25 mm
(0.006 ~ 0.010 in)0.50 mm
(0.020 in)
Side clearance (installed) 0.030 ~ 0.065 mm
(0.0012 ~ 0.0026 in)0.12 mm
(0.005 in)
2nd ring:
Type Taper ----
Dimensions (B × T) 0.80 × 2.75 mm (0.03 × 0.11 in) ----
End gap (installed) 0.30 ~ 0.45 mm
(0.012 ~ 0.018 in)0.80 mm
(0.031 in)
Side clearance 0.020 ~ 0.055 mm
(0.0008 ~ 0.0022 in)0.12 mm
(0.005 in)
Oil ring:
Dimensions (B × T) 1.50 × 2.25 mm (0.06 × 0.09 in) ----
End gap (installed) 0.10 ~ 0.40 mm
(0.004 ~ 0.016 in)----
Crankshaft:
Crank width “A”55.95 ~ 56.00 mm
(2.203 ~ 2.205 in)----
Runout limit “C”0.03 mm (0.0012 in) 0.05 mm
(0.002 in)
Big end side clearance “D”0.15 ~ 0.45 mm
(0.0059 ~ 0.0177 in)0.50 mm
(0.02 in)
Small end free play “F”0.4 ~ 1.0 mm (0.02 ~ 0.04 in) 2.0 mm
(0.08 in) Item Standard Limit
T
B
B
T
B
T

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:
USAEUROPE, CDN,
ZA, AUS, NZ
Type/manufacturer FCR-MX37/KEIHIN←
I. D. mark 5UM1 00 5UM2 10
Main jet (M.J) #185 #172
Main air jet (M.A.J)ø2.0←
Jet needle (J.N) OBDVS-4 OBELP-4
Cutaway (C.A) 1.5←
Pilot jet (P.J) #40←
Pilot air jet (P.A.J) #75←
Pilot outlet (P.O)ø0.9←
Pilot screw (example) (P.S) 2 1-7/8
Bypass (B.P)ø1.0←
Valve seat size (V.S)ø3.8←
Starter jet (G.S) #72←
Leak jet (Acc.P) #90←
Float height (F.H) 8 mm (0.31 in)←
Engine idle speed 1,900 ~ 2,100 r/min←
Intake vacuum 26.7 ~ 32.0 kPa
(200 ~ 240 mmHg,
7.87 ~ 9.45 inHg)←
Hot starter lever free play 3 ~ 6 mm
(0.12 ~ 0.24 in)← Item Standard Limit

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

MAINTENANCE SPECIFICATIONS
2 - 11
SPEC
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race. Silencer M8 × 1.25 2 35 3.5 25
Silencer clamp M8 × 1.25 1 19 1.9 13
Spark arrester (for USA) M6 × 1.0 3 10 1.0 7.2
Silencer end pipe (for USA) M6 × 1.0 1 10 1.0 7.2
Crankcase M6 × 1.0 11 12 1.2 8.7
Crankcase bearing stopper M6 × 1.0 11 10 1.0 7.2
Crankcase bearing stopper (crankshaft) M6 × 1.0 4 10 1.0 7.2
Left crankcase cover M6 × 1.0 8 10 1.0 7.2
Idle gear cover (starter motor) M6 × 1.0 3 10 1.0 7.2
Idle gear plate M6 × 1.0 2 10 1.0 7.2
Right crankcase cover M6 × 1.0 8 10 1.0 7.2
Clutch cover M6 × 1.0 7 10 1.0 7.2
Crankcase oil drain bolt M10 × 1.25 1 20 2.0 14
Drive chain sprocket cover M6 × 1.0 2 8 0.8 5.8
Kick shaft ratchet wheel guide M6 × 1.0 2 12 1.2 8.7
Kickstarter crank M8 × 1.25 1 33 3.3 24
Starter clutch M6 × 1.0 6 16 1.6 11
Primary drive gear M18 × 1.0 1 75 7.5 54
Clutch spring M6 × 1.0 5 8 0.8 5.8
Clutch boss M16 × 1.0 1 60 6.0 43
Push lever shaft M6 × 1.0 1 10 1.0 7.2
Drive sprocket M18 × 1.0 1 75 7.5 54
Drive axle oil seal stopper M6 × 1.0 2 10 1.0 7.2
Segment M8 × 1.25 1 30 3.0 22
Shift guide M6 × 1.0 2 10 1.0 7.2
Stopper lever M6 × 1.0 1 10 1.0 7.2
Shift pedal M6 × 1.0 1 12 1.2 8.7 Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb

MAINTENANCE SPECIFICATIONS
2 - 12
SPEC
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension: USA, CDN EUROPE AUS, NZ, ZA
Front fork travel 300 mm (11.8 in)←←
Fork spring free length 460 mm (18.1 in)←←
Spring rate, STD K = 4.31 N/mm
(0.44 kg/mm,
24.6 lb/in)K = 4.12 N/mm
(0.42 kg/mm,
23.5 lb/in)K = 4.22 N/mm
(0.43 kg/mm,
24.1 lb/in)
Optional spring/spacer Yes←←
Oil capacity568 cm
3
(20.0 lmp oz,
19.2 US oz) 573 cm3
(20.2 lmp oz,
19.4 US oz) 578 cm3
(20.3 lmp oz,
19.5 US oz)
Oil level 135 mm (5.31 in) 130 mm (5.12 in) 125 mm (4.92 in)

(From top of outer tube with inner
tube and damper rod fully com-
pressed without spring.)80 ~ 150 mm
(3.15 ~ 5.91 in)←←
Oil grade Suspension oil
“01”←←
Inner tube outer diameter 46 mm (1.81 in)←←
Front fork top end 5 mm (0.20 in)←10 mm (0.39 in)
Rear suspension: USA, CDN EUROPE AUS, NZ, ZA
Shock absorber travel 132 mm (5.20 in)←←
Spring free length
260 mm (10.24 in)←←
Fitting length 245 mm (9.65 in)
246.5 mm (9.70 in)245 mm (9.65 in)
240.5 ~ 258.5 mm
(9.47 ~ 10.18 in)←←
Spring rate, STD K = 49.0 N/mm
(5.00 kg/mm,
280.0 lb/in)K = 46.0 N/mm
(4.70 kg/mm,
263.2 lb/in)K = 50.0 N/mm
(5.10 kg/mm,
285.6 lb/in)
Optional spring Yes←←
Enclosed gas pressure
1,000 kPa
(10 kg/cm2, 142 psi)
←←
Swingarm:
Swingarm free play limit
End ---- 1.0 mm
(0.04 in)

MAINTENANCE SPECIFICATIONS
2 - 13
SPEC
Wheel: USA, CDN, ZA EUROPE, AUS, NZ
Front wheel type Spoke wheel←----
Rear wheel type Spoke wheel←----
Front rim size/material 21 × 1.60/Aluminum←----
Rear rim size/material 18 × 1.85/Aluminum 18 × 2.15/Aluminum ----
Rim runout limit:
Radial ---- ---- 2.0 mm
(0.08 in)
Lateral ---- ---- 2.0 mm
(0.08 in)
Drive chain:
Type/manufacturer DID520VM/DAIDO ----
Number of links 113 links + joint ----
Chain slack 40 ~ 50 mm (1.6 ~ 2.0 in) ----
Chain length (10 links) ---- 150.1 mm
(5.91 in)
Front disc brake:
Disc outside dia. × Thickness 250 × 3.0 mm (9.84 × 0.12 in)
250 × 2.5 mm
(9.84
× 0.10 in)
Pad thickness 4.4 mm (0.17 in) 1.0 mm
(0.04 in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 27.0 mm (1.063 in) × 2 ----
Brake fluid type DOT #4 ----
Rear disc brake:
Disc outside dia. × Thickness 245 × 4.0 mm (9.65 × 0.16 in)
245 × 3.5 mm
(9.65
× 0.14 in)
Deflection limit ---- 0.15 mm
(0.006 in)
Pad thickness 6.4 mm (0.25 in) 1.0 mm
(0.04 in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 25.4 mm (1.000 in) × 1 ----
Brake fluid type DOT #4 ----
Brake lever and brake pedal:
Brake lever position 95 mm (3.74 in) ----
Brake pedal height
(vertical height above footrest top)5 mm (0.20 in) ----
Clutch lever free play (lever end) 8 ~ 13 mm (0.31 ~ 0.51 in) ----
Throttle grip free play 3 ~ 5 mm (0.12 ~ 0.20 in) ----Item Standard Limit

MAINTENANCE SPECIFICATIONS
2 - 14
SPEC
NOTE:
1. First, tighten the steering nut approximately 38 Nm (3.8 m  kg, 27 ft  lb) by using the steering
nut wrench, then loosen the steering nut one turn.
2. Retighten the steering nut 7 Nm (0.7 m  kg, 5.1 ft  lb). Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Upper bracket and outer tube M8 × 1.25 4 23 2.3 17
Lower bracket and outer tube M8 × 1.25 4 20 2.0 14
Upper bracket and steering stem M24 × 1.0 1 145 14.5 105
Handlebar upper holder and upper bracket M8 × 1.25 4 28 2.8 20
Steering stem and steering ring nut M28 × 1.0 1 Refer to NOTE.
Front fork and front fork cap bolt M48 × 1.0 2 30 3.0 22
Front fork and base valve M30 × 1.0 2 55 5.5 40
Front fork cap bolt and damper rod M12 × 1.25 2 29 2.9 21
Front fork bleed screw and front fork cap bolt M5 × 0.8 2 1 0.1 0.7
Front fork and front fork protector M6 × 1.0 6 10 1.0 7.2
Front fork and brake hose holder M6 × 1.0 2 10 1.0 7.2
Front fork and brake hose cover (M8) M8 × 1.25 1 16 1.6 11
(M6) M6 × 1.0 1 7 0.7 5.1
Throttle grip cap M5 × 0.8 2 4 0.4 2.9
Front brake master cylinder M6 × 1.0 2 9 0.9 6.5
Brake lever mounting bolt M6 × 1.0 1 6 0.6 4.3
Brake lever mounting nut M6 × 1.0 1 6 0.6 4.3
Brake lever position locknut M6 × 1.0 1 5 0.5 3.6
Front brake hose guide M5 × 0.8 2 4 0.4 2.9
Clutch lever holder M5 × 0.8 2 4 0.4 2.9
Hot starter lever holder M5 × 0.8 2 4 0.4 2.9
Hot starter lever mounting nut M5 × 0.8 1 2 0.2 1.4
Light switch M4 × 0.7 2 2 0.2 1.4
Front brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
Front brake hose union bolt M10 × 1.25 2 30 3.0 22
Front brake caliper M8 × 1.25 2 23 2.3 17
Pad pin plug M10 × 1.0 2 3 0.3 2.2
Front brake caliper and pad pin M10 × 1.0 1 18 1.8 13
Rear brake caliper and pad pin M10 × 1.0 1 18 1.8 13
Brake caliper and bleed screw M8 × 1.25 2 6 0.6 4.3
Front wheel axle and axle nut M16 × 1.5 1 105 10.5 75
Front wheel axle holder M8 × 1.25 4 23 2.3 17
Front brake disc M6 × 1.0 6 12 1.2 8.7
Rear brake disc M6 × 1.0 6 14 1.4 10
Brake pedal M8 × 1.25 1 26 2.6 19
Rear brake master cylinder M6 × 1.0 2 11 1.1 8.0
Rear brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
Rear brake hose union bolt M10 × 1.25 2 30 3.0 22
Rear wheel axle and axle nut M20 × 1.5 1 125 12.5 90