Yamaha XMAX 250 YP250R Owner's Manual page 39

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
PERIODIC MAINTENANCE AND MINOR REPAIR
the spark plug is a medium-to-
light tan (the ideal color when the
motorcycle is ridden normally).
NOTE:
If the spark plug shows a distinctly dif-
ferent color, the engine could be defec-
tive. Do not attempt to diagnose such
problems yourself. Instead, have a
Yamaha dealer check the motorcycle.
2. Check the spark plug for electro-
de erosion and excessive carbon
or other deposits, and replace it if
necessary.
Specified spark plug:
NGK DR8EA
To install the spark plug
6-6
1. Measure the spark plug gap with
a wire thickness gauge and, if
necessary, adjust the gap to spe-
cification.
Spark plug gap:
0,7mm (0,027in)
2. Clean the surface of the spark
plug gasket and its mating surfa-
ce, and then wipe off any grime
from the spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then
tighten it to the specified torque.
Tightening torque:
Spark plug:
18 Nm (1,8 m•kgf, 13,01 ft•lbf)
NOTE:
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4 ~
1/2 turn past finger tight. However,
the spark plug should be tightened to
the specified torque as soon as pos-
sible.
4. Install the spark plug cap.
6