Checking The Piston Rings - Yamaha YZF-R1 98 Service Manual

CONNECTING RODS AND PISTONS
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e. Calculate the piston-to-cylinder clear-
ance w ith the follow ing form ula.
Piston-to-cylinder clearance =
Cylinder bore "C" –
Piston skirt diameter "P"
Piston-to-cylinder clearance
0.030 ~ 0.055 mm
<Limit>: 0.12 mm
f. If out of specification, replace the
crankcases, and the pistons and pis-
ton rings as a set.
EB404410

CHECKING THE PISTON RINGS

1. M easure:
• piston ring side clearance
Out of specification → Replace the pis-
ton and piston rings as a set.
NOTE:
Before m easuring the piston ring side
clearance, elim inate any carbon depos-
its from the piston ring grooves and pis-
ton rings.
Piston ring side clearance
Top ring
0.030 ~ 0.065 mm
<Limit>: 0.115 mm
2nd ring
0.020 ~ 0.055 mm
<Limit>: 0.115 mm
2. Install:
• piston ring
(into the cylinder)
NOTE:
Level the piston ring in the cylinder w ith
the piston crow n.
a 5 m m
ENG