Yamaha 4XE-F8197-10 Motorcycle User Manual


 
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ENG
INSPECTION AND REPAIR
TAPPET COVER AND CAM SPROCKET
COVER
1.Inspect:
Tappet covers (intake 1 and exhaust 2)
Cam sprocket cover 3
O-rings 4
Cracks/Damage Replace.
CYLINDER AND PISTON
1.Eliminate:
Carbon deposits
(from the piston crown and ring grooves.)
2.Inspect:
Cylinder and piston walls
Vertical scratches Rebore or replace
cylinder and piston.
3.Measure:
Piston-to-cylinder clearance
*********************************
Measurement steps:
First steps
Measure the cylinder bore “C” with a cyl-
inder bore gauge 1.
a 40 mm (1.6 in) from the cylinder top
NOTE:
Measure the cylinder bore "C" in parallel to
and at right angles to the cylinder matching
surface. Then, find the average of the mea-
surements.
If out of the specification, rebore or
replace the cylinder, and the piston and
piston rings as a set.
Standard Wear limit
Cylinder
bore “C”
70.97 ~ 71.02 mm
(2.794 ~ 2.796 in)
71.10 mm
(2.799 in)
C=
X+Y
2
4