Checking The Piston Pin - Yamaha R1 Series 2015 Service Manual

2. Install:
• Piston ring
(into the cylinder)
TIP
Use the piston crown to level the piston ring near
bottom of cylinder "a", where cylinder wear is
lowest.
3. Measure:
• Piston ring end gap
Out of specification
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.
Top ring
End gap (installed)
0.15–0.25 mm (0.0059–0.0098 in)
Limit
0.50 mm (0.0197 in)
2nd ring
End gap (installed)
0.65–0.80 mm (0.0256–0.0315 in)
Limit
1.15 mm (0.0453 in)
Oil ring
End gap (installed)
0.10–0.35 mm (0.0039–0.0138 in)
b. Upper of cylinder
CONNECTING RODS AND PISTONS
Replace the piston
a
b
5-75
EAS30749

CHECKING THE PISTON PIN

The following procedure applies to all of the pis-
ton pins.
1. Measure:
• Piston pin outside diameter "a"
Out of specification
Piston pin outside diameter
16.991–17.000 mm (0.6689–
0.6693 in)
Limit
16.971 mm (0.6681 in)
2. Measure:
• Piston pin bore inside diameter "b"
Out of specification
Piston pin bore inside diameter
17.002–17.013 mm (0.6694–
0.6698 in)
Limit
17.043 mm (0.6710 in)
3. Calculate:
• Piston-pin-to-piston-pin-bore clearance
Out of specification
and piston as a set.
Piston-pin-to-piston-pin-bore clearance = Piston
pin bore inside diameter "b" - Piston pin outside
diameter "a"
Replace the piston pin.
Replace the piston.
Replace the piston pin