Yamaha BEARTRACKER YFM250XC, Service Manual

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ENG
INSPECTION AND REPAIR
2.Inspect:
●
Cam lobes
Pitting/Scratches/Blue discoloration
→
Replace.
3.Measure:
●
Cam lobes
Use a Micrometer.
Out of specification
→
Replace.
Cam lobe
Limit “A”
Cam lobe
Limit “B”
Intake
36.437 mm
(1.435 in)
30.031 mm
(1.182 in)
Exhaust
36.482 mm
(1.436 in)
30.152 mm
(1.187 in)
ROCKER ARM AND ROCKER ARM SHAFT
1.Inspect:
●
Rocker arm shafts
●
Rocker arms
Wear/Damage
→
Replace.
*********************************
Rocker arm shaft and arm inspection steps:
●
Inspect the two areas on the rocker arm
for signs of unusual wear.
1) Rocker arm shaft hole.
2) Cam-lobe-contact surface.
Excessive wear
→
Replace.
●
Inspect the surface condition of the rocker
arm shaft.
Pitting/Scratches/blue discoloration
→
Replace/Check lubrication.
●
Measure the inside diameter
a
of the
rocker arm hole.
Out of specification
→
Replace.
●
Measure the outside diameter
b
of the
rocker arm shaft.
Out of specification
→
Replace.
Rocker arm inside diameter:
12.000 ~ 12.018 mm
(0.4724 ~ 0.4731 in)
Rocker arm shaft outside diameter:
11.985 ~ 11.991 mm
(0.4718 ~ 0.4721 in)
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