Yamaha YZ450F(Y Owner's Manual page 28

Piston off-set
Piston pin bore inside diameter
Piston pin outside diameter
Piston rings:
Top ring:
Type
Dimensions (B × T)
End gap (installed)
Side clearance (installed)
2nd ring:
Type
Dimensions (B × T)
End gap (installed)
Side clearance
Oil ring:
Dimensions (B × T)
End gap (installed)
Crankshaft:
Crank width "A"
Runout limit "C"
Big end side clearance "D"
Small end free play "F"
Balancer:
Balancer drive method
Item
MAINTENANCE SPECIFICATIONS
Standard
1 mm (0.0394 in)
18.004–18.015 mm (0.7088–0.7093 in)
17.991–18.000 mm (0.7083–0.7087 in)
Barrel
1.2 × 3.5 mm (0.05 × 0.14 in)
0.20–0.30 mm (0.008–0.012 in)
0.030–0.065 mm (0.0012–0.0026 in)
Taper
1.00 × 3.35 mm (0.04 × 0.13 in)
0.35–0.50 mm (0.014–0.020 in)
0.020–0.055 mm (0.0008–0.0022 in)
2.0 × 2.9 mm (0.08 × 0.11 in)
0.2–0.5 mm (0.01–0.02 in)
61.95–62.00 mm (2.439–2.441 in)
0.03 mm (0.0012 in)
0.15–0.45 mm (0.0059–0.0177 in)
0.4–1.0 mm (0.02–0.04 in)
Gear
2-6
Limit
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18.045 mm
(0.7104 in)
17.971 mm
(0.7075 in)
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0.55 mm (0.022
in)
0.12 mm (0.005
in)
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0.85 mm (0.033
in)
0.12 mm (0.005
in)
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0.05 mm (0.002
in)
0.50 mm (0.02
in)
2.0 mm (0.08
in)
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