High-Altitude Clutch Tuning; Gearing; Spring Suspension Adjustment - Arctic Cat Cougar Service Manual

ADJUSTMENTS FOR SPECIAL USE
Worn out
Corrosive gases formed by combustion and
high voltage sparks have eroded the electrodes.
Spark plugs in this condition require more volt-
age to fire under hard acceleration. Replace with
a new spark plug.
Preignition
If the electrodes are melted, preigmtwn is
almost certainly the cause. Check for carburetor
mounting or intake manifold leaks and overad-
vanced ignition timing. It is also possible that a
plug with a heat range that is too hot is being
used. Find the cause of the preignition before
returning the engine into service.
HIGH-ALTITUDE CLUTCH TUNING
Standard clutch and drive specifications are
listed in Tables 3-4. When the snowmobile is
operated at an altitude of more than 4,000 feet
(1 ,200 meters), it may be necessary to adjust the
clutch to compensate for engine power loss. If
the clutch is not adjusted, the engine may bog
down when the belt engages. The engine may
also bog when running in deep snow. Both con-
ditions can lead to premature drive belt failure.
Refer to Chapter Thirteen for complete clutch
service procedures.
GEARING
Depending upon altitude, snow and track con-
ditions, a different gear ratio may be required.
Snow conditions that offer few rough sections
may require less gear reduction. Less optimum
snow conditions or more rugged terrain require
more gear reduction. Refer to the sprocket speci-
fications chart in Table 4. Replacement sprock-
ets and chains can be purchased through Arctic
Cat dealers. Refer to Chapter Fourteen for
sprocket and chain replacement procedures.
133
SPRING SUSPENSION ADJUSTMENT
You can adjust the suspension to accommo-
date rider weight and snow conditions.
Correct suspension adjustment is arrived at
largely through a matter of trial-and-error tuning.
There are several fundamental points that must
be understood and applied before the suspension
can be successfully adjusted to your needs.
Ski pressure-the load on the skis relative to
the load on the track-is the primary factor con-
trolling handling performance. If the ski pressure
is too light, the front of the machine tends to float
and steering control becomes vague, with the
machine tending to drive straight ahead rather
than tum, and wander when running straight at
steady throttle.
On the other hand, if ski pressure is too heavy,
the machine tends to plow during cornering and
the skis dig in during straight-line running rather
than stay on top of the snow.
Ski pressure for one snow condition is not
necessarily good for another condition. For in-
stance, if the surface is very hard and offers little
steering traction, added ski pressure-to permit
the skis to dig into the snow-is desirable. Also,
the hard surface will support the skis and not
allow them to penetrate when the machine is
running in a straight line under power.
On the other hand, if the surface is soft and
tacky, lighter ski pressure is desirable to prevent
the skis from sinking into the snow. Also, the
increased traction afforded by the snow will al-
low the skis to tum with light pressure.
It is apparent, then, that good suspension ad-
justment involves a thorough analysis relating to
ski pressure versus conditions. The suspension
has been set at the factory to work in most
conditions encountered by general riding. How-
ever, when the snowmobile is operated in vary-
ing or more difficult conditions, the suspension
should be adjusted. It is important to remember
that suspension tuning is a compromise. An ad-