Arctic Cat 2014 XF 2-STROKE, Руководство по обслуживанию

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NOTE: Before starting the snowmobile in extremely
cold temperatures, the drive belt should be removed
and warmed up to room temperature. Once the drive
belt is at room temperature, install the drive belt (see
Drive Belt sub-section in the Drive Train/Track/Brake
Systems section of this manual).
Genuine Parts
When replacement of parts is necessary, use only genuine
Arctic Cat parts. They are precision-made to ensure high
quality and correct fit.
Varying Altitude
Operation
Operating a snowmobile at varying altitudes requires recal-
ibration of drive system components. Consult the appropri-
ate specification sheet on Cat Tracker Online.
Following are basic altitude theories for clutching,
engine, suspension, and track.
CLUTCHING
On a normally-aspirated engine as altitude changes,
engine horsepower changes with it. As you go up in alti-
tude, the engine loses horsepower. Because of this, the
continuously variable transmission (CVT) system needs
to be calibrated to compensate for the horsepower loss.
At altitudes above 5000 ft, the engine loses peak horse-
power but will also lose horsepower at engagement speed.
For this reason, calibrating the drive system is usually
needed in order to attain acceptable performance. Changing
drive clutch engagement speed can be done several ways.
Some of the methods will affect other characteristics of
CVT operation, so you must be careful what you change.
Drive clutch springs are the most common way to increase
engagement speed; however, by simply changing the cam
arms to a lighter weight from the heavier sea level cam arm,
you will gain some engagement speed.
Other more complicated methods exist such as engage-
ment notches and changing the position of the cam arm
center of gravity in relation to the roller. This is called
“tucking the weight” and can be used, but, like the
engagement notch, it can hurt belt life.
The driven clutch will also play a part in CVT tuning for
high altitude operation. A steeper helix (torque bracket)
angle in the driven clutch will mean a quicker up-shift. A
shallower angle will mean a slower up-shift. If the up-shift
is too quick, due to a very steep helix, RPM will be pulled
down under the peak operating RPM of the engine (where
the horsepower is) and performance will suffer. The engine
may even bog. If you have a helix that is too shallow, the
engine may over-rev or have poor acceleration. Usually,
angles shallower than the sea level calibrations work best.
The driven spring will also affect driven clutch tuning.
Tighten the spring, and RPM will increase. Loosen the
spring, and RPM will decrease. The spring should be used
to fine-tune and complement the helix selection.
ENGINE
A normally aspirated engine will generate more horsepower
at sea level than it does at higher altitudes. The reason is that
the higher you go, less oxygen is available for the engine to
use during its combustion process. Less oxygen means it
needs less fuel to obtain the correct air/fuel ratio to operate
properly. This is why the fuel ratio has to be recalibrated.
High altitude engines operate as though they have a lower
compression ratio. This, along with less oxygen and less
fuel, means that the engine generates less horsepower. All
of these characteristics will become more evident the higher
the altitude.
SUSPENSION
The different riding styles of the individual operator, the
varying snow conditions, and the type of terrain are all
factors that affect the suspension at high altitude. Trail
riding versus powder snow riding versus combination
riding will all require different suspension settings.
The normal setting for front ski suspension is as little spring
pre-load tension as possible for powder snow riding allow-
ing the skis to float across the snow with the least amount
of resistance. Trail riding will require more spring tension
to carry the varying load more effectively. Many different
settings and spring tensions to consider exist when adjust-
ing for riding style and snow conditions.
The rear suspension has a number of spring settings that
produce different riding characteristics.
The front arm spring and shock will also affect the ride and
handling when either on a trail or in powder snow. A strong
spring setting on this shock will cause the snowmobile to
tend to “dig” more when riding in the powder snow rather
than climbing up on top of the snow. But, it will work more
effectively when riding on a trail. A softer spring setting
will allow the front of the rear suspension to collapse much
quicker and change the angle of the track to the snow. A
more gradual angle will tend to raise the snowmobile up on
the snow rather than digging into it.
Many possible variables and adjustments to the rear sus-
pension exist depending on snow conditions, riding style,
and type of terrain. These adjustments can be made to indi-
vidualize the snowmobile to the riding style of the operator.
CAUTION
Running the engine with the drive belt removed could
result in serious engine damage and drive clutch failure.