Checking The Spark Plug - Yamaha Xmax 250 Owner's Manual

PERIODIC MAINTENANCE AND MINOR REPAIR

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 maintenance and lubrication
chart. In addition, the condition of the
spark plug can reveal the condition of
the engine.
To remove the spark plug
1. Open the seat. (See page 3-13.)
2. Remove the storage compart-
6
ment under the seat by removing
the bolts.
2
1
1. Storage compartment
2. Screws
EAUS1280
3. Remove the spark plug cap.
4. Remove the spark plug as
shown, with the spark plug
wrench included in the owner's
tool kit.
To check the spark plug
1. Check that the porcelain insula-
tor around the center electrode of
NOTE:
If the spark plug shows a distinctly
different color, the engine could be
defective. Do not attempt to diagnose
such problems yourself. Instead, have
a Yamaha dealer check the motorcy-
cle.
2. Check the spark plug for electro-
To install the spark plug
1. Spark plug gap
6-7
the spark plug is a medium-to-
light tan (the ideal color when the
motorcycle is ridden normally).
de erosion and excessive carbon
or other deposits, and replace it if
necessary.
Specified spark plug:
NGK / DR8EA