Yamaha WR400F(M) Owner's Service Manual page 78

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
Decompression device:
Type
Cable free play
Air filter oil grade:
MAINTENANCE SPECIFICATIONS
Item
T
T
B
T
Standard
18.004 ~ 18.015 mm
(0.7088 ~ 0.7093 in)
17.991 ~ 18.000 mm
(0.7083 ~ 0.7087 in)
B
Barrel
1.2 3.5 mm (0.05
0.20 ~ 0.35 mm
(0.008 ~ 0.014 in)
0.030 ~ 0.065 mm
(0.0012 ~ 0.0026 in)
B
Taper
1.00 3.35 mm (0.04
0.40 ~ 0.55 mm
(0.016 ~ 0.022 in)
0.020 ~ 0.055 mm
(0.0008 ~ 0.0022 in)
2.0 2.9 mm (0.08
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
Manual
5 ~ 9 mm (0.20 ~ 0.35 in)
Engine oil
2 - 7
SPEC
Limit
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0.14 in) ----
0.7 mm
(0.028 in)
0.13 mm
(0.005 in)
----
0.13 in) ----
0.8 mm
(0.031 in)
0.13 mm
(0.005 in)
0.11 in) ----
----
----
0.05 mm
(0.002 in)
0.50 mm
(0.02 in)
2.0 mm
(0.08 in)
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