Yamaha 25BMH, Service Manual

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CRANKSHAFT AND CYLINDER BODY
POWR
5-36
E
NOTE:
Push the piston ring into the cylinder with
the piston crown.
3. Measure:
• Piston ring side clearance
(use a thickness gauge)
Out of specification
→
Replace.
NOTE:
When measuring the piston ring side clear-
ance, the outside of the piston ring should
be flush with the piston wall.
CHECKING THE CRANKSHAFT
1. Measure:
• Crank width
(use the digital caliper)
Out of specification
→
Repair/replace.
Piston ring side clearance
0.03 - 0.07 mm (0.001 - 0.003 in)
Crank width
56.90 - 56.95 mm
(2.2401 - 2.2421 in)
Crank width
153.7 - 154.0 mm
(6.0512 - 6.0630 in)
Crank width
39.9 - 40.1 mm
(1.5709 - 1.5787 in)
b
a
b
c