Yamaha YFM90RA Model Vehicle User Manual


 
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ENG
CYLINDER HEAD
EBS00220
REMOVING THE CYLINDER HEAD
1. Align:
“T” mark on the rotor
(with the stationary pointer on the crank-
case)
a. Turn the crankshaft clockwise with a wrench.
b. Align the “T” mark on the rotor with the
stationary pointer on the crankcase.
When the “T” mark is aligned with the sta-
tionary pointer, the piston is at Top Dead
Center (TDC).
TIP
TDC on compression stroke check:
Both rocker arms must have a valve clear-
ance when the camshaft sprocket alignment
mark is aligned with the cylinder head
alignment mark
If not, give the crankshaft one counterclock-
wise turn to meet the above condition.
2.Remove:
bolt, flg. (small head)
cyl. head cover assy.
nut
TIP
Working in a crisscross pattern, loosen e-
ach nut 1/4 of a turn.
, and the round hole in
camshaft sprocket away from the cylinder he-
ad.
carb. joint assy.
nut
washer
cap, camshaft
tensioner assy.
bolt, flg. (small head)