Operation Manual

PERIODIC MAINTENANCE AND MINOR REPAIR
6-6
6
To install the panel
1. Place the panel in the original po-
sition, and then install the screws.
2. Install the seat.
EAU01880
Checking the spark plugs
The spark plugs are important engine
components, which should be checked
periodically, preferably by a Yamaha
dealer. Since heat and deposits will
cause any spark plug to slowly erode,
they should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plugs can re-
veal the condition of the engine.
The porcelain insulator around the cen-
ter electrode of each spark plug should
be a medium-to-light tan (the ideal col-
or when the motorcycle is ridden nor-
mally), and all spark plugs installed in
the engine should have the same color.
If any 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.
If a spark plug shows signs of electrode
erosion and excessive carbon or other
deposits, it should be replaced.
Before installing a spark plug, the spark
plug gap should be measured with a
wire thickness gauge and, if necessary,
adjusted to specification.
a. Spark plug gap
Specified spark plug:
CR8E (NGK) or
U24ESR-N (DENSO)
Spark plug gap:
0.7–0.8 mm
E_4br.book Page 6 Wednesday, July 25, 2001 1:40 PM