ENG
VALVES AND VALVE SPRINGS
CHECKING THE VALVE SPRINGS
The following procedure applies to all of the valve
springs.
1. Measure:
• spring free length
a
Out of specification
-->
Replace.
2. Measure:
• compressed spring force
a
Out of specification
-->
Replace.
b
Installed length
3. Measure:
• spring tilt
a
Out of specification
-->
Replace.
Spring tilt limit (all)
2.5
o
/1.6 mm (2.5°/0.063 in)
a
Spring free length
Intake (inside)
36.17mm (1.424 in)
<limit>: 34.47mm (1.357 in)
Exhaust (inside)
36.17mm (1.424 in)
<limit>: 34.47mm (1.357 in)
Intake (outside)
36.63mm (1.442 in)
<limit>: 34.63mm (1.363 in)
Exhaust (outside)
36.63mm (1.442 in)
<limit>: 34.63mm (1.363 in)
a
b
Compressed spring force
Inside
75 ~ 91 N at 30.5 mm
(7.50 ~ 9.10 kgf at 30.5 mm,
17 ~ 20.5 lbf at 1.20 in)
Outside
128.5 ~ 157.9 N at 32.0 mm
(12.85 ~ 15.79 kgf.m at 32.0 mm
29 ~ 36 lbf at 1.26 in)
a
5-28
Summary of Contents for YBR250 2007
Page 1: ...YBR250 SERVICE MANUAL 5D1 F8197 E0 2007 ...
Page 2: ......
Page 359: ...YAMAHA MOTOR DA AMAZÔNIA LTDA ...
