Yamaha XV16AL, Service Manual

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ENG
CYLINDERS AND PISTONS
f. If out of specification, replace the cylin-
der, and the piston and piston rings as a
set.
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Piston-to-cylinder clearance
0.025 ~ 0.050 mm
(0.001 ~ 0.002 in)
<Limit>: 0.15 mm (0.006 in)
EAS00263
CHECKING THE PISTON RINGS
1. Measure:
• 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
Top ring
0.03 ~ 0.08 mm
(0.0012 ~ 0.0031 in)
<Limit>: 0.12 mm (0.0047 in)
2nd ring
0.03 ~ 0.07 mm
(0.0012 ~ 0.0028 in)
<Limit>: 0.12 mm (0.0047 in)
2. Install:
• piston ring
(into the cylinder)
NOTE:
Level the piston ring in the cylinder with the
piston crown.
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 can-
not be measured. If the oil ring rail’s gap is
excessive, replace all three piston rings.
5