Checking The Spark Plug - Yamaha XT660R Service Manual

ADJUSTING THE THROTTLE CABLE FREE PLAY/

CHECKING THE SPARK PLUG

c. Tighten the locknut.
_
After adjusting the throttle cable free play,
start the engine and turn the handlebars to
the right and to the left to ensure that this
does not cause the engine idling speed to
change.
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EAS00060
CHECKING THE SPARK PLUG
1. Disconnect:
• spark plug cap
2. Remove:
• spark plug
CAUTION:
_
Before removing the spark plug, blow away
any dirt accumulated in the spark plug well
with compressed air to prevent it from fall-
ing into the cylinder.
3. Check:
• spark plug type
4. Check:
• electrode 1
• insulator 2
5. Clean:
• spark plug
6. Measure:
• spark plug gap a
3 - 19
WARNING
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Incorrect → Change.
Spark plug type (manufacturer)
CR7E (NGK)
Damage/wear → Replace the spark plug.
Abnormal color → Replace the spark plug.
Normal color is medium-to-light tan.
(with a spark plug cleaner or wire brush)
(with a thickness gauge)
Out of specification → Regap.
Spark plug gap
0.7 ~ 0.8 mm (0.028 ~ 0.031 in)
CHK
ADJ
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