Engine; Adjusting The Valve Clearance - Yamaha XT250X 2008 Service Manual

EAS20471

ENGINE

EAS20520

ADJUSTING THE VALVE CLEARANCE

The following procedure applies to all of the
valves.
NOTE:
Valve clearance adjustment should be made
G
on a cold engine, at room temperature.
When the valve clearance is to be measured or
G
adjusted, the piston must be at top dead center
(TDC) on the compression stroke.
1. Remove:
Fuel tank
G
Refer to "FUEL TANK" on page 6-1.
2. Remove:
Intake tappet cover "1"
G
Exhaust tappet cover "2"
G
Camshaft sprocket cover "3"
G
1
3
3. Remove:
Spark plug cap
G
Spark plug
G
4. Remove:
Timing mark accessing screw "1"
G
Crankshaft end cover "2"
G
5. Measure:
Valve clearance
G
Out of specification → Adjust.
All manuals and user guides at all-guides.com
2
3-5
Valve clearance (cold)
Intake
0.05–0.10 mm (0.0020–0.0039 in)
Exhaust
0.10–0.15 mm (0.0039–0.0059 in)
MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
a. Turn the crankshaft counterclockwise.
b. When the piston is in the compression stroke,
align camshaft sprocket mark "a" with cylin-
der head mark "b". This is the Top Dead Cen-
ter (TDC).
c. Make sure that generator rotor mark "c"
aligns with generator rotor cover mark "d".
d. Measure the valve clearance using special
thickness gauge "1".
Out of specification → Adjust.
Special thickness gauge
90890-01399
ENGINE
1