Yamaha YZ450F Owner's Service Manual page 36

Piston:
Piston to cylinder clearance
Piston size "D"
Measuring point "H"
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)
Item
MAINTENANCE SPECIFICATIONS
Standard
0.020–0.045 mm (0.0008–0.0018 in)
96.965–96.980 mm (3.8175–3.8181 in)
9.0 mm (0.354 in)
Zero mm (Zero in)
18.004–18.015 mm (0.7088–0.7093 in)
17.991–18.000 mm (0.7083–0.7087 in)
Barrel
1.00 × 3.30 mm (0.04 × 0.13 in)
0.20–0.30 mm (0.008–0.012 in)
0.015–0.065 mm (0.0015–0.0026 in)
Taper
1.00 × 3.10 mm (0.04 × 0.12 in)
0.35–0.50 mm (0.014–0.020 in)
0.020–0.060 mm (0.0008–0.0024 in)
1.5 × 2.55 mm (0.06 × 0.10 in)
0.2–0.5 mm (0.01–0.02 in)
2-6
Limit
0.1 mm (0.004
in)
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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)
0.120 mm
(0.0047 in)
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0.85 mm (0.033
in)
0.120 mm
(0.0047 in)
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