Yamaha YFM660FS, Supplementary Service Manual

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SPEC
MAINTENANCE SPECIFICATIONS
Piston:
Piston to cylinder clearance 0.05 ~ 0.07 mm
(0.0020 ~ 0.0028 in) 0.15 mm
(0.0059 in)
Piston size “D” 99.945 ~ 99.995 mm
(3.9348 ~ 3.9368 in) ----
Measuring point “H” 2.5 mm (0.10 in) ----
Piston off-set 1.0 mm (0.0394 in) ----
Offset direction Intake side ----
Piston pin bore inside diameter 22.004 ~ 22.015 mm
(0.8663 ~ 0.8667 in) 22.045 mm
(0.8679 in)
Piston pin outside diameter 21.991 ~ 22.000 mm
(0.8658 ~ 0.8661 in) 21.971 mm
(0.8650 in)
Piston rings:
Top ring
Type Barrel ----
Dimensions (B
×
T) 1.2
×
3.8 mm
(0.0472
×
0.1496 in)
----
End gap (installed) 0.30 ~ 0.45 mm
(0.0118 ~ 0.0177 in) 0.70 mm
(0.0276 in)
Side clearance (installed) 0.04 ~ 0.08 mm
(0.0016 ~ 0.0031 in) 0.13 mm
(0.0051 in)
Item Standard Limit
H
D
T
B