Yamaha 2006 YZFR6V, Service Manual

Page: 273 / 444

CONNECTING RODS AND PISTONS
5-62
NOTE:
Level the piston ring into the cylinder with the
piston crown.
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.
EAS24440
CHECKING THE PISTON PINS
The following procedure applies to all of the pis-
ton pins.
1. Check:
• Piston pin
Blue discoloration/grooves
→
Replace the
piston pin and then check the lubrication sys-
tem.
2. Measure:
• Piston pin outside diameter “a”
Out of specification
→
Replace the piston pin.
3. Measure:
• Piston pin bore diameter “b”
Out of specification
→
Replace the piston.
4. Calculate:
• Piston-pin-to-piston-pin-bore clearance
Out of specification
→
Replace the piston pin
and piston as a set.
a. 5 mm (0.20 in)
Piston ring
Top ring
End gap (installed)
0.25–0.35 mm (0.0098–0.0138
in)
Limit
0.55 mm (0.0217 in)
2nd ring
End gap (installed)
0.70–0.80 mm (0.0276–0.0315
in)
Limit
1.00 mm (0.0394 in)
Oil ring
End gap (installed)
0.10–0.35 mm (0.0039–0.0138
in)
Piston pin outside diameter
14.991–15.000 mm (0.5902–
0.5906 in)
Limit
14.971 mm (0.5894 in)
Piston pin bore inside diameter
15.002–15.013 mm (0.5906–
0.5911 in)
Limit
15.043 mm (0.5922 in)
• Piston-pin-to-piston-pin-bore clearance =
Piston pin bore diameter “b” -
Piston pin outside diameter “a”
Piston-pin-to-piston-pin-bore
clearance
0.002–0.022 mm (0.00007–
0.00068 in)