Yamaha TW200M 1999 Owner's Manual page 48

PERIODIC MAINTENANCE AND MINOR REPAIR
Inspection
The spark plug is an important
engine component and is easy to
1
inspect. The condition of the spark
plug can indicate the condition of
2
the engine.
The ideal color on the white insula-
3 tor around the center electrode is a
medium-to-light tan color for a
motorcycle that is being ridden
4
normally.
Do not attempt to diagnose such
5
problems yourself. Instead, take
the motorcycle to a Yamaha deal-
6
er. You should periodically remove
and inspect the spark plug because
7
heat and deposits will cause any
spark plug to slowly break down
8
and erode. If electrode erosion
becomes excessive, or if carbon
and other deposits are excessive,
9
you should replace the spark plug
with the specified plug.
Specified spark plug:
DR8EA (NGK) OR
X24ESR-U (DENSO)
1
1. Spark plug gap
Installation
1. Measure the electrode gap
with a wire thickness gauge
and, if necessary, adjust the
gap to specification.
Spark plug gap:
0.6 ~ 0.7 mm
2. Clean the gasket surface. Wipe
off any grime
threads.
3. Install the spark plug and tight-
en it to the specified torque.
6-8
Tightening torque:
Spark plug:
17.5 Nm (1.75 m0kg)
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.
from the