Checking The Valve Springs - Yamaha XC50V Service Manual

VALVES AND VALVE SPRINGS
a
b
a
a
EAS00241

CHECKING THE VALVE SPRINGS

The following procedure applies to all of the valve
springs.
1. Measure:
8 valve spring free length a
Out of specification
spring.
Valve spring free length
Intake valve spring
39.35 mm (1.549 in)
<Limit>: 37.38 mm (1.472 in)
Exhaust valve spring
41.57 mm (1.637 in)
<Limit>: 39.49 mm (1.555 in)
2. Measure:
8 compressed valve spring force a
Out of specification
spring.
b Installed length
Compressed valve spring force (in-
stalled)
Intake valve spring
9.3~10.7 kg at 28 mm (20.5 ~ 23.6 lb
at 1.102 in)
Exhaust valve spring
11.0 ~ 12.7 kg at 30 mm (24.3 ~ 28.0
lb at 1.181 in)
3. Measure:
8 valve spring tilt a
Out of specification
spring.
Spring tilt limit
Intake valve spring
1.7 mm (0.067 in) ( 2.5° )
Exhaust valve spring
1.8 mm (0.071 in)( 2.5° )
5-24
ENG
Replace the valve
Replace the valve
Replace the valve