Checking The Piston Pins - Yamaha XP500 Service Manual

CYLINDER AND PISTON
2. Install:
• piston ring
(into the cylinder)
NOTE:
Level the piston ring in the cylinder with the
piston crown as shown.
a 10 mm (0.39 in)
3. Measure:
• piston ring end gap
Out of specification → Replace the piston
ring.
NOTE:
The oil ring expander spacer's end gap cannot
be measured. If the oil ring rail's gap is exces-
sive, replace all three piston rings.
Piston ring end gap
EAS00266

CHECKING THE PISTON PINS

The following procedure applies to all of the
piston pins.
1. Check:
• piston pin
Blue discoloration/grooves → Replace the
piston pin and then check the lubrication
system.
5 - 34
ENG
Top ring
0.15 ~ 0.25 mm
(0.0059 ~ 0.0098 in)
<Limit>: 0.50 mm (0.0197 in)
2nd ring
0.40 ~ 0.50 mm
(0.0157 ~ 0.0197 in)
<Limit>: 0.75 mm (0.0295 in)
Oil ring
0.10 ~ 0.35 mm
(0.0039 ~ 0.0138 in)