Advertisement
1. Cylinder head cover
EAU01673
Checking the spark plugs
The spark plugs are important engine
components, which are easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plugs 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.
1. Spark plug wrench
To remove a spark plug
1. Remove
the appropriate
spark
plug cover (rear right or front left)
by pulling it off as shown.
2. Remove the spark plug cap.
3. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner's tool kit.
To check the spark plugs
1. Check that the porcelain insulator
around
the center
electrode
on
each spark plug is a medium-to-
light tan (the ideal color when the
motorcycle is ridden normally).
6-8
PERIODIC MAINTENANCE AND MINOR REPAIR
2. Check that all spark plugs installed
in the engine have the same color.
NOTE:
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.
3. Check each spark plug for elec-
trode erosion and excessive car-
bon or other deposits, and replace
it if necessary.
Specified spark plug:
BPR7ES (NGK) or
W22EPR-U (DENSO)
Advertisement
