Checking The Piston Rings - Yamaha CS50 Service Manual

INSPECTION AND REPAIR
EAS00263

CHECKING THE PISTON RINGS

1. Measure:
• piston ring side clearance
Out of specification
and piston rings as a set.
Use a Feeler Gauge
NOTE:
Before measuring the piston ring side clearan-
ce, eliminate any carbon deposits from the
piston ring grooves and piston rings.
2. Install:
• piston ring
(into the cylinder)
NOTE:
Level the piston ring into the cylinder with the
piston crown.
k a 20 mm
3. Measure:
• piston ring end gap
Out of specification
ring.
Use a Feeler Gauge
4-14
Replace the piston
Piston ring side clearance
Top ring
0.03 ~ 0.05 mm
<Limit>: 0.1 mm
2nd ring
0.03 ~ 0.05 mm
<Limit>: 0.1 mm
Replace the piston
Piston ring end gap
Top ring
0.15 ~ 0.35 mm
<Limit>: 0.6 mm
2nd ring
0.15 ~ 0.35 mm
<Limit>: 0.6 mm
ENG