Checking The Camshaft - Yamaha F200C Service Manual

b Previous contact width
8. If the valve seat contact area is too nar-
row and situated near the bottom edge of
the valve face, use a 60° cutter to cut the
bottom edge of the valve seat. If neces-
sary, use a 45° cutter to center the area
and set its width.
b Previous contact width
9. Apply a thin, even layer of lapping com-
pound onto the valve seat, and then lap
the valve using a valve lapper (commer-
cially obtainable).
CAUTION:
Do not get the lapping compound on the
valve stem and valve guide.
69J1D11
10. After every lapping procedure, be sure to
clean off any remaining lapping com-
pound from the cylinder head and the
valve.
11. Check the valve seat contact area of the
valve again.

Checking the camshaft

1. Check the timing chain sprockets for
damage or wear. Replace the camshaft if
necessary.
2. Measure the cam lobe. Replace if out of
specification.
Cam lobe a:
Intake:
45.30–45.40 mm
(1.7835–1.7874 in)
Exhaust:
45.35–45.45 mm
(1.7854–1.7894 in)
Cam lobe b:
Intake:
35.95–36.05 mm
(1.4154–1.4193 in)
Exhaust:
35.95–36.05 mm
(1.4154–1.4193 in)
Cylinder head
5-38
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