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SPEC
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GENERAL SPECIFICATIONS
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: YZ250FN (USA)
YZ250FLC (EUROPE)
YZ250F(N) (CDN, AUS, NZ, ZA)
Model code number: 5NL1 (USA)
5NL2 (EUROPE)
5NL4 (CDN, AUS, NZ, ZA)
Dimensions:
Overall length 2,165 mm (85.2 in)
Overall width 827 mm (32.6 in)
Overall height 1,303 mm (51.3 in)
Seat height 998 mm (39.3 in)
Wheelbase 1,475 mm (58.1 in)
Minimum ground clearance 382 mm (15.0 in)
Basic weight:
With oil and full fuel tank 104.5 kg (230 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 Kickstarter
Lubrication system: Dry sump
Oil type or grade:
Engine oil (For USA and CDN)
At 5 ˚C (40 ˚F) or higher
Yamalube 4 (20W-40) or SAE 20W-40 type
SH motor oil
(Non-Friction modified)
At 15 ˚C (60 ˚F) or lower
õ
Yamalube 4 (10W-30) or SAE 10W-30 type
SH motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
(Non-Friction modified)
(Except for USA and CDN)
API “SH” 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
2
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SPEC
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GENERAL SPECIFICATIONS
Oil capacity:
Engine oil
Periodic oil change 1.5 L (1.32 Imp qt, 1.59 US qt)
With oil filter replacement 1.6 L (1.41 Imp qt, 1.69 US qt)
Total amount 1.7 L (1.50 Imp qt, 1.80 US qt)
Coolant capacity (including all routes): 0.9 L (0.79 Imp qt, 0.95 US qt)
Air filter: Wet type element
Fuel:
Type Premium unleaded fuel with a research octane
number of 95 or higher. (Except for AUS)
Unleaded fuel only (For AUS)
Tank capacity 8.0 L (1.76 Imp gal, 2.11 US gal)
Carburetor:
Type FCR-MX37
Manufacturer KEIHIN
Spark plug:
Type/manufacturer CR8E/NGK
U24ESR-N/DENSO
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 48/13 (3.692)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 30/14 (2.143)
2nd 28/16 (1.750)
3rd 29/20 (1.450)
4th 27/22 (1.227)
5th 25/24 (1.042)
Chassis:
Frame type Semi double cradle
Caster angle 27.1˚
Trail 117.4 mm (4.62 in)
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN, ZA, AUS, NZ
and F)
80/100-21 MT320 (For EUROPE except F)
Size (rear) 100/90-19 57M (For USA, CDN, ZA, AUS, NZ
and F)
100/90-19 MT320 (For EUROPE except F)
Tire pressure (front and rear) 100 kPa (1.0 kg/cm
2
, 15 psi)
2
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SPEC
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GENERAL SPECIFICATIONS
Brake:
Front brake type Single disc brake
Operation Right hand operation
Rear brake type Single disc brake
Operation Right foot operation
Suspension:
Front suspension Telescopic fork
Rear suspension Swingarm (link type monocross suspension)
Shock absorber:
Front shock absorber Coil spring/oil damper
Rear shock absorber Coil spring/gas, oil damper
Wheel travel:
Front wheel travel 300 mm (11.8 in)
Rear wheel travel 315 mm (12.4 in)
Electrical:
Ignition system CDI magneto
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MAINTENANCE SPECIFICATIONS
Piston pin bore inside diameter16.002 ~ 16.013 mm
(0.6300 ~ 0.6304 in)16.043 mm
(0.6316 in)
Piston pin outside diameter15.991 ~ 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)
Decompression device:
Type Manual ----
Cable free play 5 ~ 9 mm (0.20 ~ 0.35 in) ----Item Standard Limit
T
B
B
T
B
T
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SPEC
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MAINTENANCE SPECIFICATIONS
Lubrication system:
Oil filter type Wire mesh 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 107.8 mm (4.2 in) ----
Height 220 mm (8.7 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure110 kPa (1.1 kg/cm
2
, 15.6 psi)----
Radiator capacity (total) 0.56 L (0.49 lmp qt, 0.59 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit
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MAINTENANCE SPECIFICATIONS
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
Decompression shaft M6
´
1.0 1 7 0.7 5.1
Decompression cable guide M6
´
1.0 1 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 3 0.3 2.2
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 delivery pipe 2 M6
´
1.0 1 10 1.0 7.2
Oil hose M6
´
1.0 3 10 1.0 7.2
Oil hose clamp — 2 2 0.2 1.4
Oil strainer and frame M18
´ 1.5 1 90 9.0 65
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 cover M5 ´ 0.8 1 4 0.4 2.9
Air filter joint M5 ´ 0.8 2 5 0.5 3.6
Air filter joint and air filter case M5 ´ 0.8 5 1 0.1 0.7
Air filter element M6 ´ 1.0 1 2 0.2 1.4
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
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MAINTENANCE SPECIFICATIONS
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 20 2.0 14
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
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 10 1.0 7.2
Kick shaft ratchet wheel guide M6 ´ 1.0 2 12 1.2 8.7
Kickstarter crank M8 ´ 1.25 1 33 3.3 24
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
Segument 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 Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
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MAINTENANCE SPECIFICATIONS
CHASSIS
Item Standard Limit
Steering system:
Steering bearing type Taper roller bearing ----
Front suspension: USA, CDN
AUS, NZ, ZAEUROPE
Front fork travel 300 mm (11.8 in)¬----
Fork spring free length 460 mm (18.1 in)¬455 mm (17.9 in)
Spring rate, STD K = 4.31 N/mm
(0.44 kg/mm,
24.6 lb/in)K = Approx.
4.21 N/mm
(0.43 kg/mm,
24.1 lb/in)----
Optional spring/spacer Yes¬----
Oil capacity 568 cm
3
(20.0 lmp oz,
19.2 US oz) ¬----
Oil level 140 mm (5.51 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)¬----
Rear suspension: USA, CDN,
AUS, NZ, ZAEUROPE
Shock absorber travel 132 mm (5.20 in)¬----
Spring free length 260 mm
(10.24 in)275 mm
(10.83 in)----
Fitting length 248 mm
(9.76 in)262 mm
(10.31 in)----
242 ~ 260 mm
(9.53 ~ 10.24 in)257 ~ 275 mm
(10.12 ~ 10.83 in)----
Spring rate, STD K = 47.0 N/mm
(4.80 kg/mm,
268.8 lb/in)K = Approx.
49.0 N/mm
(5.00 kg/mm,
280.0 lb/in)----
Optional spring Yes¬----
Enclosed gas pressure 1,000 kPa
(10 kg/cm
2,
142 psi)¬----
Swingarm:
Swingarm free play limit
End ---- 1.0 mm (0.04 in)