Yamaha RX10K, Supplementary Service Manual

Page: 315 / 523

5-48
CRANKCASE
ENG
NOTE:
2nd step:
S
Measure piston skirt diameter “P” with the
micrometer.
a 5 mm (0.20 in) from the bottom edge of the piston.
Piston size (standard) (P):
73.955
X
73.970 mm
(2.9116
X
2.9122 in)
S
If out of specification, replace the piston and
piston rings as a set.
3rd step:
S
Calculate the piston-to-cylinder clearance
with the following formula.
Piston-to-cylinder clearance =
Cylinder bore “C” –
Piston skirt diameter “P”
Piston-to-cylinder clearance:
0.030
X
0.055 mm
(0.0012
X
0.0022 in)
<Limit>: 0.12 mm (0.0047 in)
S
If out of specification, replace the cylinder,
and the piston and piston rings as a set.
3. Measure:
S
Side clearance (piston rings)
Use the thickness gauge
1
Out of specification
!
Replace the piston
and piston rings as a set.
Eliminate the carbon deposits from the piston
ring grooves and rings before measuring the
side clearance.
Piton rings side clearance:
Top ring
0.030
X
0.065 mm
(0.0012
X
0.0026 in)
2nd ring
0.020
X
0.055 mm
(0.0008
X
0.0022 in)