Piston Ring Inspection - Yamaha SR125 1997 Service Manual

CYLINDER AND PISTON
EB402110

PISTON RING INSPECTION

1. Measure:
: Side clearance
Out of specification ! Replace the piston
and the piston rings as a set.
NOTE:
Eliminate the carbon deposits from the piston
ring grooves and rings before measuring the
side clearance.
Side clearance:
2. Position:
: Piston ring
(into the cylinder)
NOTE:
Push the ring with the piston crown so that the
ring will be at a right angle to the cylinder bore.
a 5 mm
3. Measure:
: End gap
Out of specification ! Replace.
NOTE:
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:
4-23
ENG
Top ring: <Limit>
0.03 0.07 mm <0.15 mm>
2nd ring: <Limit>
0.02 0.06 mm <0.15 mm>
Top ring: <Limit>
0.15 0.35 mm <0.60 mm>
2nd ring: <Limit>
0.15 0.35 mm <0.60 mm>
Oil ring:
0.3 0.9 mm