Yamaha FX Nytro FX10X, Service Manual

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5-61
ENG
CONNECTING RODS AND PISTONS
4. Install:
• Piston ring
(into the cylinder)
NOTE:
Level the piston ring in the cylinder with the piston
crown.
a
5.0 mm (0.20 in)
5. Measure:
• Piston ring end gap
Out of specification
→
Replace the piston
rings as a set.
NOTE:
The oil ring expander spacer end gap cannot be
measured. If the oil ring rail gap is excessive,
replace all three piston rings.
6. Inspect:
• Piston pin
Blue discoloration/grooves
→
Replace the
piston pin and then check the lubrication sys-
tem.
Piston ring end gap:
Top ring:
0.33 ~ 0.45 mm (0.013 ~ 0.018 in)
2nd ring:
0.70 ~ 0.85 mm (0.028 ~ 0.033 in)
Oil ring:
0.20 ~ 0.60 mm (0.008 ~ 0.024 in)
7. Measure:
• Piston pin outside diameter
Out of specification
→
Replace the piston pin.
Piston pin outside diameter:
18.991 ~ 19.000 mm
(0.7477 ~ 0.7480 in)