Checking The Spark Plug - Yamaha XMAX YP250R Owner's Manual

PERIODIC MAINTENANCE AND ADJUSTMENT
1. Screw
To install the panel
Place the panel in the original posi-
tion, and then install the screws.
6

Checking the spark plug

The spark plug is an important engine
component, which should be chec-
ked periodically, preferably by a
Yamaha dealer. Since heat and depo-
sits will cause any spark plug to
slowly erode, it should be removed
and checked in accordance with the
periodic maintenance and lubrication
chart. In addition, the condition of the
spark plug can reveal the condition of
the engine.
The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally). If the spark plug shows a
distinctly different color, the engine
could be operating improperly. Do not
attempt to diagnose such problems
yourself. Instead, have a Yamaha
dealer check the vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon
or other deposits, it should be repla-
ced.
6-9
EAU19622
Specified spark plug:
NGK/DPR8EA-9
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
1
ZAUM0037
1. Spark plug gap
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.