Yamaha MX-800, Service Manual

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ENGINE
PISTONS, CAMSHAFT, CRANKCASE, AND CRANKSHAFT
2.
Check:
• Camshaft lobe dimensions “a” and “b”
Out of specification

Replace.
3.
Check:
• Surface of camshaft gear teeth
Crack/damage/wear

Replace.
4.
Check:
• Camshaft journal diameter “a”
Out of specification

Replace.
CHECKING THE VALVE LIFTERS
The following procedure applies to all of the valve lifters.
a
b
Camshaft lobe dimensions
Lobe height “a” (Intake):
32.885 mm (1.2947 in)
Limit:
32.785 mm (1.2907 in)
Lobe height “a” (Exhaust):
33.957 mm (1.3369 in)
Limit:
33.857 mm (1.3330 in)
Base circle diameter “b” (Intake):
26.000 mm (1.0236 in)
Limit:
25.900 mm (1.0197 in)
Base circle diameter “b” (Exhaust):
26.000 mm (1.0236 in)
Limit:
25.900 mm (1.0197 in)
a
a
Camshaft journal diameter:
16.965–16.990 mm (0.6679–0.6689 in)
Limit:
16.950 mm (0.6673 in)