Checking The Piston Pins - Yamaha STAR XVS95CE 2DX1 2014 Service Manual

a. 10 mm (0.39 in)
3. Measure:
• Piston ring end gap
Out of specification → Replace the piston
ring.
TIP
The oil ring expander spacer end gap cannot be
measured. If the oil ring rail's gap is excessive,
replace all three piston rings.
Piston ring
Top ring
End gap (installed)
0.15–0.30 mm (0.0059–0.0118
in)
Limit
0.60 mm (0.0236 in)
2nd ring
End gap (installed)
0.30–0.45 mm (0.0118–0.0177
in)
Limit
0.80 mm (0.0315 in)
Oil ring
End gap (installed)
0.20–0.70 mm (0.0079–0.0276
in)
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.
CYLINDERS AND PISTONS
Piston pin outside diameter
20.991–21.000 mm (0.8264–
0.8268 in)
Limit
20.971 mm (0.8256 in)
3. Measure:
• Piston pin bore diameter "b"
Out of specification → Replace the piston.
Piston pin bore inside diameter
21.004–21.015 mm (0.8269–
0.8274 in)
Limit
21.045 mm (0.8285 in)
4. Calculate:
• Piston-pin-to-piston-pin-bore clearance
Out of specification → Replace the piston pin
and piston as a set.
• Piston-pin-to-piston-pin-bore clearance =
Piston pin bore diameter "b" -
Piston pin outside diameter "a"
Piston-pin-to-piston-pin-bore
clearance
0.004–0.024 mm (0.00016–
0.00094 in)
Limit
0.074 mm (0.0029 in)
5-39