Checking The Piston Rings - Yamaha XVS250 2001 Service Manual

CYLINDERS AND PISTONS
EB404410

CHECKING THE PISTON RINGS

1. Measure:
D piston ring side clearance
Out of specification  Replace the piston
and piston rings as a set.
NOTE:
Before measuring the piston ring side clear-
ance, eliminate any carbon deposits from the
piston ring grooves and piston rings.
Piston ring side clearance
2. Install:
D piston ring
(into the cylinder)
NOTE:
Using the piston crown pash the ring into the cyl-
inder so that the ring will be at a right angle to the
cylinder bore.
a 20 mm from the top of the cylinder
3. Measure:
D 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
5-30
ENG
Top ring
0.02 0.06 mm
<Limit>: 0.12 mm
2nd ring
0.02 0.06 mm
<Limit>: 0.12 mm
Top ring
0.15 0.30 mm
<Limit>: 0.4 mm
2nd ring
0.15 0.30 mm
<Limit>: 0.4 mm
Oil ring
0.3 0.9 mm