blistered porcelain insulator surface. This condition
is commonly caused by a spark plug with a heat
range that is too hot. If the spark plug heat range is
correct, consider the following causes:
1. Lean air/fuel mixture.
2. Improperly operating ignition component.
3. Engine lubrication system malfunction.
4. Cooling system malfunction.
5. Engine air leak.
6. Improper spark plug installation (over-tightening).
7. No spark plug gasket.
Worn out
Corrosive gases formed by combustion and high
voltage sparks have eroded the electrodes. A spark
plug in this condition requires more voltage to fire
under hard acceleration. Install a new spark plug.
Preignition
If the electrodes are melted, preignition is proba-
bly the cause. Check for carburetor mounting or in-
take manifold leaks and advanced ignition timing.
The plug heat range may also be too hot. Find the
cause of the preignition before returning the engine
into
service.
For
additional
information
on
preignition, refer to Chapter Two.
ENGINE OIL
Engine Oil Level Check
Check the engine oil level through the sight glass
(C,
Figure 9
) in the alternator cover.
1. Start the engine and let it reach normal operating
temperature.
2. Stop the engine and let the oil settle.
CAUTION
If the bike is not parked correctly, the
oil level reading will be incorrect.
3. Have an assistant hold the motorcycle so it
stands straight up and level
.
4. The oil level should be between the maximum
and minimum window marks. If necessary, remove
the oil filler cap (D,
Figure 9
) from the top of the al-
ternator cover and add enough of the recommended
oil (see
Table 4
) to raise the oil to the proper level.
Do not overfill the crankcase.
5. Reinstall the oil filler cap and tighten it securely.
Engine Oil and Filter Change
The recommended oil and filter change interval is
specified in
Table 1
. This assumes that the motorcy-
cle is operated in moderate climates. If a motorcycle
is operated under dusty conditions, the oil will get
dirty more quickly and should be changed more fre-
quently than recommended.
Select an engine oil with a API service classifica-
tion of SE, SF or SG. The classification is on the con-
tainer label. Try to use the same brand of oil at each
oil change and avoid the use of oil additives. They
may cause clutch slippage. Refer to
Table 4
and se-
lect the correct oil viscosity for the anticipated ambi-
ent air temperatures (not the engine oil temperature).
CAUTION
Do not use engine oil classified as
Energy Conserving.
These types of
66
CHAPTER THREE
26
27
1. Oil filter cover bolt
2. Oil filter outer cover
3. Cap bolt
4. Cap
5. O-ring
6. Oil filter