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SPEC
2 - 1
EC200000
SPECIFICATIONS
EC211000
GENERAL SPECIFICATIONS
Model name: YZ450FT (USA, CDN, AUS, NZ)
YZ450F (EUROPE, ZA)
Model code number: 5XD5 (USA)
5XD6 (EUROPE)
5XD8 (CDN, AUS, NZ, ZA)
Dimensions: USA, ZA,
AUS, NZEUR
(Except for F)F, CDN
Overall length 2,190 mm
(86.2 in)2,195 mm
(86.4 in)←
Overall width 827 mm
(32.6 in)← ←
Overall height 1,300 mm
(51.2 in)1,302 mm
(51.3 in)1,303 mm
(51.3 in)
Seat height 999 mm
(39.3 in)1,001 mm
(39.4 in)←
Wheelbase 1,493 mm
(58.8 in)← ←
Minimum ground clearance 379 mm
(14.9 in)381 mm
(15.0 in)←
Dry weight:
Without oil and fuel 100.0 kg (220 lb)
Engine:
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Single cylinder, forward inclined
Displacement 449 cm
3 (15.8 Imp oz, 15.2 US oz)
Bore × stroke 95.0 × 63.4 mm (3.74 × 2.50 in)
Compression ratio 12.3 : 1
Starting system Kick starter
Lubrication system: Dry sump
GENERAL SPECIFICATIONS
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SPEC
2 - 2 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 modi-
fied)
(Except for USA and CDN)
API “SG” or higher grade
Oil capacity:
Engine oil
Periodic oil change 1.0 L (0.88 Imp qt, 1.06 US qt)
With oil filter replacement 1.1 L (0.97 Imp qt, 1.16 US qt)
Total amount 1.2 L (1.06 Imp qt, 1.27 US qt)
Coolant capacity (including all routes): 1.2 L (1.06 Imp qt, 1.27 US qt)
Air filter: Wet type element
Fuel:
Type Premium unleaded gasoline only with a
research octane number of 95 or higher.
Tank capacity 7.0 L (1.54 Imp gal, 1.85 US gal)
Carburetor:
Type FCR MX39
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
-20
-4-10
140
3010
5020
6830
8640 50
104
122 ˚CTemp.
˚F
10W-30
10W-40
20W-40
20W-50
15W-40
GENERAL SPECIFICATIONS
2
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SPEC
2 - 3 Transmission:
Primary reduction system Gear
Primary reduction ratio 61/23 (2.652)
Secondary reduction system Chain drive
Secondary reduction ratio 51/14 (3.643)
Transmission type Constant mesh, 4-speed
Operation Left foot operation
Gear ratio: 1st 27/14 (1.929)
2nd 25/16 (1.563)
3rd 23/18 (1.278)
4th 21/20 (1.050)
Chassis:
Frame type Semi double cradle
Caster angle 27.1°
Trail 116 mm (4.57 in) (For USA, ZA, AUS, NZ)
117 mm (4.61 in) (For EUROPE except F)
118 mm (4.65 in) (For F, CDN)
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN, ZA, AUS, NZ
and F)
80/100-21 51R (For EUROPE except F)
Size (rear) 110/90-19 62M (For USA, CDN, ZA, AUS, NZ
and F)
110/90-19 NHS (For EUROPE except F)
Tire pressure (front and rear) 100 kPa (1.0 kgf/cm
2, 15 psi)
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
GENERAL SPECIFICATIONS
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SPEC
2 - 7 Piston rings:
Top ring:
Type Barrel ----
Dimensions (B × T) 1.2 × 3.5 mm (0.05 × 0.14 in) ----
End gap (installed) 0.20 ~ 0.30 mm
(0.008 ~ 0.012 in)0.55 mm
(0.022 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) 1.00 × 3.35 mm (0.04 × 0.13 in) ----
End gap (installed) 0.35 ~ 0.50 mm
(0.014 ~ 0.020 in)0.85 mm
(0.033 in)
Side clearance 0.020 ~ 0.055 mm
(0.0008 ~ 0.0022 in)0.12 mm
(0.005 in)
Oil ring:
Dimensions (B × T) 2.0 × 2.9 mm (0.08 × 0.11 in) ----
End gap (installed) 0.2 ~ 0.5 mm (0.01 ~ 0.02 in) ----
Crankshaft:
Crank width “A”61.95 ~ 62.00 mm
(2.439 ~ 2.441 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)
Balancer:
Balancer drive method Gear ----
Air filter oil grade: Foam-air-filter oil or equivalent
oil ---- Item Standard Limit
T
B
B
T
B
T
MAINTENANCE SPECIFICATIONS
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SPEC
2 - 9 Lubrication system:
Oil filter type Paper type ----
Oil pump type Trochoid type ----
Tip clearance “A”0.12 mm or less
(0.0047 in or less)0.20 mm
(0.008 in)
Tip clearance “B”0.09 ~ 0.17 mm
(0.0035 ~ 0.0067 in)0.24 mm
(0.009 in)
Side clearance 0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)0.17 mm
(0.007 in)
Bypass valve setting pressure 40 ~ 80 kPa (0.4 ~ 0.8 kg/cm
2,
5.69 ~ 11.38 psi)----
Cooling:
Radiator core size
Width 117.8 mm (4.6 in) ----
Height 260 mm (10.2 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure 110 kPa (1.1 kg/cm
2, 15.6 psi) ----
Radiator capacity (total) 0.71 L (0.62 Imp qt, 0.75 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit
MAINTENANCE SPECIFICATIONS
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SPEC
2 - 10 Item Standard
Lubrication chart:
Pressure feed
Splashed scavenge
Oil strainer
Oil pan Oil pump rotor 2
Oil pump rotor 1
Oil tank
Oil filter
Check ball
Cylinder head
Crank pinPiston pinPiston
Drive axleMain axleTransmission gears
Camshaft
Valve lifter
MAINTENANCE SPECIFICATIONS
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SPEC
2 - 11 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 28 2.8 20
Cylinder head (stud bolt) M6 × 1.0 2 7 0.7 5.1
M8 × 1.25 1 15 1.5 11
(bolt) M10 × 1.25 4 Refer to NOTE.*
1
(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
Timing chain tensioner M6 × 1.0 2 10 1.0 7.2
Tensioner cap bolt M6 × 1.0 1 7 0.7 5.1
Timing chain guide (rear) M6 × 1.0 2 10 1.0 7.2
Exhaust pipe (nut) M8 × 1.25 1 13 1.3 9.4
(bolt) M8 × 1.25 1 24 2.4 17
Silencer M8 × 1.25 2 35 3.5 25
Silencer clamp M8 × 1.25 1 16 1.6 11
Exhaust pipe protector M6 × 1.0 3 10 1.0 7.2
Clamp (cylinder head side) M5 × 0.8 1 3 0.3 2.2
Clamp (carburetor side) M4 × 0.7 1 3 0.3 2.2
Air filter case M6 × 1.0 2 8 0.8 5.8
Air filter joint clamp M6 × 1.0 1 3 0.3 2.2
Air filter joint and air filter case M5 × 0.8 1 4 0.4 2.9
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 element M6 × 1.0 1 2 0.2 1.4
Radiator panel (upper) M6 × 1.0 2 10 1.0 7.2
Radiator M6 × 1.0 6 10 1.0 7.2
Radiator hose clamp M6 × 1.0 8 2 0.2 1.4
Radiator pipe 1, 2 M10 × 1.0 2 10 1.0 7.2
Impeller M8 × 1.25 1 14 1.4 10
Water pump housing cover M6 × 1.0 3 10 1.0 7.2
Coolant drain bolt 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 9 0.9 6.5
Engine oil drain bolt (oil filter) M6 × 1.0 1 10 1.0 7.2
Oil filter cover M6 × 1.0 2 10 1.0 7.2
Oil delivery pipe 1 M10 × 1.25 1 20 2.0 14
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 2 8 0.8 5.8
Oil check bolt M6 × 1.0 1 10 1.0 7.2
MAINTENANCE SPECIFICATIONS
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SPEC
2 - 12
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.
NOTE:
*1: Tighten the cylinder head bolts to 30 Nm (3.0 m kg, 22 ft lb) in the proper tightening sequence,
remove and retighten the cylinder head bolts to 20 Nm (2.0 m kg, 14 ft lb) in the proper tightening
sequence, and then tighten the cylinder head bolts further to reach the specified angle 180° in the
proper tightening sequence.Oil hose clamp—220.21.4
Clutch cover M6 × 1.0 7 10 1.0 7.2
Crankcase cover (right) M6 × 1.0 10 10 1.0 7.2
Crankcase cover (left) M6 × 1.0 8 10 1.0 7.2
Crankcase M6 × 1.0 12 12 1.2 8.7
Clutch cable holder M6 × 1.0 1 10 1.0 7.2
Oil drain bolt (crankcase rear) M10 × 1.25 1 20 2.0 14
(crankcase left) M6 × 1.0 1 10 1.0 7.2
Oil drain bolt (frame) M8 × 1.25 1 23 2.3 17
Oil strainer (frame) M14 × 1.5 1 70 7.0 50
Crankcase bearing stopper M6 × 1.0 15 10 1.0 7.2
Drive axle oil seal stopper M6 × 1.0 2 10 1.0 7.2
Ratchet wheel guide M6 × 1.0 2 12 1.2 8.7
Kick starter M8 × 1.25 1 33 3.3 24
Screw (kick starter) M6 × 1.0 1 7 0.7 5.1
Primary drive gear M20 × 1.0 1 110 11.0 80
Clutch boss M20 × 1.0 1 75 7.5 54
Clutch cable locknut M8 × 1.25 2 7 0.7 5.1
Push lever M6 × 1.0 1 10 1.0 7.2
Clutch spring M6 × 1.0 6 8 0.8 5.8
Balancer driven gear M14 × 1.0 1 50 5.0 36
Balancer weight plate M6 × 1.0 3 10 1.0 7.2
Drive sprocket M20 × 1.0 1 75 7.5 54
Drive sprocket cover M6 × 1.0 2 8 0.8 5.8
Shift pedal M6 × 1.0 1 12 1.2 8.7
Shift guide M6 × 1.0 2 10 1.0 7.2
Stopper lever M6 × 1.0 1 10 1.0 7.2
Segment M8 × 1.25 1 30 3.0 22 Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
MAINTENANCE SPECIFICATIONS