Checking The Valve Springs - Yamaha MIO Service Manual

VALVES AND VALVE SPRINGS
h. Install the valve into the cylinder head.
i. Press the valve through the valve guide and
j. Measure the valve seat width c again. If
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EAS00241

CHECKING THE VALVE SPRINGS

The following procedure applies to all of the
valve springs.
1. Measure:
2. Measure:
b Installed length
4 - 29
onto the valve seat to make a clear impres-
sion.
the valve seat width is out of specification,
reface and lap the valve seat.
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• valve spring free length a
Out of specification → Replace the valve
spring.
Valve spring free length
Intake valve spring
35.44 mm (1.40 in)
<Limit>: 34.00 mm (1.34 in)
Exhaust valve spring
35.44 mm (1.40 in)
<Limit>: 34.00 mm (1.34 in)
• compressed valve spring force a
Out of specification → Replace the valve
spring.
Compressed valve spring force
(installed)
Intake and exhaust valve spring
146 ~ 168 N
(14.9 ~ 17.1 kgf, 32.8 ~ 37.7 lb)
at 24.1 mm (0.95 in)
ENG
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