Valve Spring Inspection - Yamaha F20A Service Manual

POWR
CAMSHAFT AND VALVES
5. Measure:
Valve stem runout
Out of specification → Replace the
valve.
Valve stem runout limit:
0.016 mm (0.0006 in)
NOTE:
When replacing the valve always use a new
valve guide and valve seal.

Valve spring inspection

1. Measure:
Valve spring free length a
Out of specification → Replace the
valve spring.
Valve spring free length:
37.85 ~ 39.85 mm
(1.491 ~ 1.569 in)
2. Measure:
Valve spring tilt a
Out of specification → Replace the
valve spring.
Valve spring tilt limit:
1.7 mm (0.06 in)
5-25
E