Checking The Spark Plugs - Yamaha YZFR1LEC Owner's Manual

PERIODIC MAINTENANCE AND MINOR REPAIR
Panels B and D
To remove one of the panels
1. Remove the rider seat. (See page
3-15.)
2. Remove the screw, and then re-
move the panel as shown.
6
1. Screw
2. Panel B
To install the panel
1. Place the panel in its original posi-
tion, and then install the screw.
EAU33990
2. Install the rider seat.
6-10

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 color
when the vehicle is ridden normally),
and all spark plugs installed in the en-
gine should have the same color. If any
spark plug shows a distinctly different
color, the engine could be defective. Do
not attempt to diagnose such problems
yourself. Instead, have a Yamaha deal-
er check the vehicle.
If a spark plug shows signs of electrode
erosion and excessive carbon or other
deposits, it should be replaced.
Specified spark plug:
NGK/CR9EK
EAU19651