Yamaha WR250F(S) Owner's Service Manual page 85

Stem runout limit
Valve seat width
Valve spring:
Free length
Set length (valve closed)
Compressed force (installed)
Tilt limit *
Direction of winding (top view)
Piston:
Piston to cylinder clearance
Piston size "D"
Measuring point "H"
Piston off-set
MAINTENANCE SPECIFICATIONS
Item
IN
EX
IN
EX
IN
EX
IN
EX
IN
EX
IN
EX
H
D
Standard
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0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)
0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in)
37.81 mm (1.49 in)
37.54 mm (1.48 in)
29.13 mm (1.15 in)
29.30 mm (1.15 in)
99 ~ 114 N at 29.13 mm
(9.9 ~ 11.4 kg at 29.13 mm,
22.27 ~ 25.57 lb at 1.15 in)
126 ~ 144 N at 29.30 mm
(12.6 ~ 14.4 kg at 29.30 mm,
28.44 ~ 32.41 lb at 1.15 in)
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Clockwise
Clockwise
0.040 ~ 0.065 mm
(0.0016 ~ 0.0026 in)
76.955 ~ 76.970 mm
(3.0297 ~ 3.0303 in)
8 mm (0.31 in)
0.5 mm (0.020 in)/IN-side
2 - 6
SPEC
Limit
0.01 mm
(0.0004 in)
1.6 mm
(0.0630 in)
1.6 mm
(0.0630 in)
36.81 mm
(1.45 in)
36.54 mm
(1.44 in)
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2.5°/ 1.7 mm
(2.5°/0.067 in)
2.5°/1.6 mm
(2.5°/0.063 in)
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----
0.1 mm
(0.004 in)
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