Checking The Valve Seats - Yamaha Sirius T110LSE Service Manual

VALVES AND VALVE SPRINGS
6. Measure:
9valve stem runout
NOTE:
9When installing a new valve, always replace
the valve guide.
9If the valve is removed or replaced, always
replace the valve stem seal.
EAS00240

CHECKING THE VALVE SEATS

The following procedure applies to all of the
valves and valve seats.
1. Eliminate:
9carbon deposits
2. Check:
9valve seat
3. Measure:
9valve seat width a
MMMMMMMMMMMMMMMMMMMMMMMM
a. Apply Mechanic's blueing dye (Dykem) b
b. Install the valve into the cylinder head.
c. Press the valve through the valve guide and
d. Measure the valve seat width.
4-26
Out of specification → Replace the valve.
Valve stem runout limit
0.01 mm (0.0004 in)
(from the valve face and valve seat)
Pitting/wear → Replace the cylinder head.
Out of specification → Replace the cylinder
head.
Valve seat width
Intake: 0.9 – 1.1 mm
(0.0354 – 0.0433 in)
Exhaust: 0.9 – 1.1 mm
(0.0354 – 0.0433 in)
<Limit>: 1.6 mm (0.06 in)
onto the valve face.
onto the valve seat to make a clear impres-
sion.
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