6-8
PERIODIC MAINTENANCE AND MINOR REPAIR
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Inspection
The spark plug is an important
engine component and is easy to
inspect. The condition of the spark
plug can indicate the condition of
the engine.
The ideal color on the white insula-
tor around the center electrode is a
medium-to-light tan color for a
motorcycle that is being ridden
normally.
Do not attempt to diagnose such
problems yourself. Instead, take
the motorcycle to a Yamaha deal-
er. You should periodically remove
and inspect the spark plug because
heat and deposits will cause any
spark plug to slowly break down
and erode. If electrode erosion
becomes excessive, or if carbon
and other deposits are excessive,
you should replace the spark plug
with the specified plug.
1.
Spark plug gap
Installation
1. Measure the electrode gap
with a wire thickness gauge
and, if necessary, adjust the
gap to specification.
2. Clean the gasket surface. Wipe
off any grime from the
threads.
3. Install the spark plug and tight-
en it to the specified torque.
NOTE:
If a torque wrench is not available
when you are installing a spark
plug, a good estimate of the cor-
rect torque is 1/4 to 1/2 turn past
finger tight. Have the spark plug
tightened to the specified torque as
soon as possible.
4. Install the spark plug cap.
Specified spark plug:
DR8EA (NGK) OR
X24ESR-U (DENSO)
Spark plug gap:
0.6 ~ 0.7 mm
Tightening torque:
Spark plug:
17.5 Nm (1.75 m
0
kg)
3XT-9-29-6 (AUS) 4/12/0 5:33 AM Page 8