Checking The Cylinders And Pistons - Yamaha YZF-R6 99 Service Manual

CONNECTING RODS AND PISTONS
4-69
EAS00262
CHECKING THE CYLINDER AND PISTONS
The following procedure applies to all of the cyl-
inders and pistons.
1. Check:
S piston wall
S cylinder wall
Vertical scratches ! Replace the crank-
cases, and the piston and piston rings as a
set.
2. Measure:
S piston-to-cylinder clearance
a. Measure cylinder bore "C" with the cylinder
bore gauge.
NOTE:
Measure cylinder bore "C" by taking side-to-
side and front-to-back measurements of the
cylinder. Then, find the average of the measure-
ments.
Cylinder bore gauge
90890-03017
Cylinder bore "C"
Max. taper "T"
Out of round "R"
b. If out of specification, replace the crank-
cases, and the piston and piston rings as a
set.
c. Measure piston skirt diameter "P" with the
micrometer.
Micrometer
90890-03008
a 4 mm from the bottom edge of the piston
Standard
d. If out of specification, replace the piston and
piston rings as a set.
ENG
65.50 65.51 mm
0.05 mm
0.05 mm
Piston size "P"
65.460 65.475 mm