Yamaha MX250 - Checking the Valve Lifter

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ENGINE
PISTON, CAMSHAFT, CRANKCASE, AND CRANKSHAFT
Out of specification/rough/eccentric wear  Replace.
3.
Check:
• Surface of camshaft gear teeth
• Decompressor
Crack/damage/wear  Replace.
4.
Check:
• Camshaft journal diameter “a”
Out of specification  Replace.
CHECKING THE VALVE LIFTER
1.
Check:
• Valve lifter
Damage  Replace.
Camshaft lobe dimensions:
Lobe height “a” (Intake):
32.1–32.2 mm (1.2638–1.2677 in)
Limit:
31.9 mm (1.2559 in)
Lobe height “a” (Exhaust):
32.5–32.6 mm (1.2795–1.2835 in)
Limit:
32.3 mm (1.2717 in)
Base circle diameter “b” (Intake):
25.98–26.08 mm (1.0228–1.0268 in)
Limit:
25.78 mm (1.015 in)
Base circle diameter “b” (Exhaust):
26.03–26.13 mm (1.0248–1.0287 in)
Limit:
25.83 mm (1.0169 in)
a
a
Camshaft journal diameter:
15.965–15.990 mm (0.6285–0.6295 in)
Limit:
15.950 mm (0.628 in)