Checking The Piston Pins - Yamaha VMAX 2009 Service Manual

Piston ring
Top ring
Ring side clearance
0.030–0.070 mm (0.0012–
0.0028 in)
Limit
0.120 mm (0.0047 in)
2nd ring
Ring side clearance
0.020–0.060 mm (0.0008–
0.0024 in)
Limit
0.120 mm (0.0047 in)
2. Install:
• Piston ring
(into the cylinder)
TIP
Level the piston ring into the cylinder with the
piston crown.
a. 9.8 mm (0.39 in)
3. Measure:
• Piston ring end gap
Out of specification → Replace the piston
ring.
TIP
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.
CONNECTING RODS AND PISTONS
Piston ring
Top ring
End gap (installed)
Limit
2nd ring
End gap (installed)
Limit
Oil ring
End gap (installed)
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.
Piston pin outside diameter
18.991–19.000 mm (0.7477–
0.7480 in)
Limit
18.971 mm (0.7469 in)
3. Measure:
• Piston pin bore inside diameter "b"
Out of specification → Replace the piston.
5-84
0.20–0.35 mm (0.0079–0.0138
in)
0.60 mm (0.0236 in)
0.40–0.55 mm (0.0157–0.0217
in)
0.80 mm (0.0315 in)
0.20–0.50 mm (0.0079–0.0197
in)