Yamaha F50D Servise Manual - page 144
Power unit
7-3
POWR
3.
Turn the flywheel magnet clockwise and
align the “1” mark
a
on the driven
sprocket with the “
▲
” mark
b
on the cyl-
inder head.
4.
Check the intake valve clearance
c
for
cylinders #1 and #2, and the exhaust
valve clearance
d
for cylinders #1 and
#3. Adjust if out of specification.
5.
Turn the flywheel magnet clockwise and
align the “4” mark
e
on the driven
sprocket with the “
▲
” mark
b
on the cyl-
inder head.
6.
Check the intake valve clearance
c
for
cylinders #3 and #4, and the exhaust
valve clearance
d
for cylinders #2 and
#4. Adjust if out of specification.
7.
Loosen the valve adjusting locknut
4
,
and then turn the adjusting screw
5
until
the specified valve clearance is obtained.
TIP:
9
To decrease the valve clearance, turn the
adjusting screw
5
in direction
f
.
9
To increase the valve clearance, turn the
adjusting screw
5
in direction
g
.
8.
Tighten the valve adjusting locknut
4
,
and then check the valve clearances.
9.
Install the cylinder head cover
3
, fuel
pump
2
, and spark plugs.
10. Connect the blowby hose
1
and spark
plug wires, and then install the flywheel
magnet cover.
Valve clearance:
Intake
c
:
0.20 ± 0.05 mm (0.008 ± 0.002 in)
Exhaust
d
:
0.30 ± 0.05 mm (0.012 ± 0.002 in)
b
a
d
c
b
e
Valve adjusting locknut:
13.5 N·m (1.4 kgf·m, 10.0 ft·lb)
4
5
f
g