3-23
ELECTRICAL
ELECTRICAL
CHECKING THE SPARK PLUG
1. Remove:
• Spark plug
2. Inspect:
• Electrode "1"
Wear/damage
→
Replace.
• Insulator color "2"
Normal condition is a medium to
light tan color.
Distinctly different color
→
Check
the engine condition.
When the engine runs for many hours
at low speeds, the spark plug insula-
tor will become sooty, even if the en-
gine and carburetor are in good
operating condition.
3. Measure:
• Plug gap "a"
Use a wire gauge or thickness
gauge.
Out of specification
→
Regap.
4. Clean the plug with a spark plug
cleaner if necessary.
5. Tighten:
• Spark plug
• Before installing a spark plug, clean
the gasket surface and plug sur-
face.
• Finger-tighten "a" the spark plug
before torquing to specification "b".
CHECKING THE IGNITION TIMING
1. Remove:
• Timing mark accessing screw "1"
2. Attach:
• Timing light
• Inductive tachometer
To the ignition coil lead (orange
lead"1").
3. Adjust:
• Engine idling speed
Refer to "ADJUSTING THE EN-
GINE IDLING SPEED" section.
4. Check:
• Ignition timing
Visually check the stationary
pointer "a" is within the firing
range "b" on the rotor.
Incorrect firing range
→
Check ro-
tor and pickup assembly.
5. Install:
• Timing mark accessing screw
Spark plug gap:
0.7–0.8 mm (0.028–
0.031 in)
Spark plug:
13 Nm (1.3 m•kg, 9.4
ft•lb)
Timing light:
YM-33277-A/90890-
03141
Summary of Contents for YZ250F X 2008
Page 2: ......
Page 3: ...YZ250F X 5XC 28199 34 E0 2008 OWNER S SERVICE MANUAL ...
Page 4: ......
Page 59: ...3 13 ENGINE INTAKE EXHAUST ...
Page 110: ...4 41 OIL PUMP 15 Rotor housing 1 Order Part name Q ty Remarks ...
Page 161: ...5 29 STEERING 9 Bearing race 2 Refer to removal section Order Part name Q ty Remarks ...
Page 170: ...5 38 REAR SHOCK ABSORBER 12 Bearing 2 Refer to removal section Order Part name Q ty Remarks ...
Page 191: ......
