Checking The Spark Plug - Yamaha XC125RR Owner's Manual

PERIODIC MAINTENANCE AND ADJUSTMENT
Panel C
To remove the panel
1 Remove the screw, and then pull the
panel off as shown.
2
2
3
4
5
6
1. Screw
2. Panel C
7
To install the panel
Place the panel in the original position,
8
and then install the screw.
9

Checking the spark plug

The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
1
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Place the vehicle on the center-
stand.
2. Remove panel B. (See page 6-8.)
3. Remove the spark plug cap.
1. Spark plug cap
4. Remove the spark plug as shown,
6-9
EAUT1836
1. Spark plug wrench
To check the spark plug
1. Check that the porcelain insulator
1
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrode
with the spark plug wrench includ-
ed in the owner's tool kit.
1
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).