Yamaha TT-R90(V) Owner's Service Manual page 66

Piston:
Piston to cylinder clearance
Piston size "D"
Piston over size
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)
MAINTENANCE SPECIFICATIONS
Item
H
D
(2nd)
(4th)
T
T
B
T
Standard
0.025 ~ 0.045 mm
(0.0010 ~ 0.0018 in)
46.960 ~ 46.975 mm
(1.8488 ~ 1.8494 in)
47.5 mm (1.8701 in)
48.0 mm (1.8898 in)
4 mm (0.16 in)
0.75 mm (0.0295 in)
13.002 ~ 13.013 mm
(0.5119 ~ 0.5123 in)
12.996 ~ 13.000 mm
(0.5117 ~ 0.5118 in)
B
Barrel
1.0 × 2.0 mm (0.04 × 0.08 in)
0.10 ~ 0.25 mm
(0.004 ~ 0.010 in)
0.030 ~ 0.065 mm
(0.0012 ~ 0.0026 in)
B
Taper
1.0 × 2.0 mm (0.04 × 0.08 in)
0.10 ~ 0.25 mm
(0.004 ~ 0.010 in)
0.020 ~ 0.055 mm
(0.0008 ~ 0.0022 in)
2.0 × 2.3 mm (0.08 × 0.09 in)
0.2 ~ 0.7 mm (0.01 ~ 0.03 in)
2 - 7
SPEC
Limit
0.15 mm
(0.0059 in)
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13.045 mm
(0.5136 in)
12.980 mm
(0.511 in)
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0.4 mm
(0.016 in)
0.12 mm
(0.005 in)
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0.4 mm
(0.016 in)
0.12 mm
(0.005 in)
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