Yamaha MAJESTY YP250, Service Manual

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4-24
CYLINDER AND PISTON
ENG
NOTE:
NOTE:
NOTE:
YP402111
PISTON RINGS INSPECTION
1. Measure:
Side clearance
Out of specification
Replace the piston
and the piston rings as a set.
Eliminate the carbon deposits from the piston
ring grooves and rings before measuring the
side clearance.
Side clearance (piston ring):
Top ring:
0.04 0.08 mm
<Limit: 0.12 mm>
2nd ring:
0.03 0.07 mm
<Limit: 0.12 mm>
2. Position:
Piston ring
(into the cylinder)
Push the ring with the piston crown so that the
ring will be at a right angle to the cylinder bore.
a 5.0 mm
3. Measure:
End gap
Out of specification
Replace.
You cannot measure the end gap on the expan-
der spacer of the oil ring. If the oil ring rails show
excessive gap, replace all three rings.
End gap:
Top ring:
0.15 0.30 mm
<Limit: 0.45 mm>
2nd ring:
0.30 0.45 mm
<Limit: 0.70 mm>
Oil ring:
0.20 0.70 mm