Yamaha JOG CS50 (Z) (2002) [77/204] Inspection and repair

ENG

INSPECTION AND REPAIR

4-14

EAS00263

CHECKING THE PISTON RINGS

1. Measure:

• piston ring side clearance

Out of specification



Replace the piston

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.

a 20 mm

3. Measure:

• piston ring end gap

Out of specification



Replace the piston

ring.

Use a Feeler Gauge 

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

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