HYOSUNG 2010 ST7, Service Manual

Page: 22 / 298

PERIODIC MAINTENANCE 2-4
If the clearance is out of specification, first remove the
cam chain tensioner, camshaft housing, camshaft.
To install the tappet shim at original position, record
the shim NO. and clearance to present by A , B ,
C , D mark on the cylinder head.
Select the tappet that agree with tappet clearance
(vertical line) and shim NO.(horizontal line) as refer to the
tappet shim selection chart. (Refer to page 9-39 40)
Adjust valve timing, install the camshaft housing and
the tension adjuster.
After the crankshaft rotate about 10 times, measure
the valve clearance.
If the clearance be not correct, adjust the standard
clearance as the same manner above.
In case of valve adjustment which is not the tappet
shim selection chart, please follow instructions of
example in the below.
For example, the intake clearance is 0.4 and the shim
is 170 (1.70 mm), select 195 (1.95 mm) of the shim
which 170 (1.70 mm) of the shim add up the excess
clearance 0.25 mm when adjust with the standard
0.15 as the intake standard clearance 0.1 0.2 mm.
Rotate the magneto rotor to set the rear cylinder s
piston at TDC(Top Dead Center) of the compression
stroke.
(Rotate the rotor 285 counter-clockwise from the
F line, and until the R line on the rotor is
aligned with the center of hole on the crankcase.)
Inspect the rear cylinder s valve clearance with the
same manner of the front cylinder.
CAUTION
Valve clearance should be checked when the
engine is cold.
If you don t rotate the crankshaft about 10
times before measuring the valve clearance,
there is no meaning of valve clearance.
A B
C D