Arctic Cat 660 cc, Service Manual

Page: 276 / 396

9-3
9
SUSPENSION SETUP BASICS
FRONT ARM SPRING TENSION
„
NOTE: Read the following information closely as
it pertains to all suspensions used in the last sev-
eral years. If there are any questions, please con-
tact the Arctic Cat Service Department.
It is desirable to run with very light front arm spring
tension. When riding in 4 in. or more of snow, the
machine will be quicker if the front spring tension is
adjusted lightly.
If the spring tension is adjusted too stiff, the track
angle at the front of the skid frame is steep. This steep
angle prevents the snowmobile from getting up on
plane and slows down by 5 to 8 mph.
When riding in sticky snow (springtime or warm days)
or hill climbing on hard snow, it may be desirable to
stiffen the front arm spring tension. When this is done,
weight is transferred back quicker. The problem with
too much front arm spring tension is that the feel of the
snowmobile becomes very short. The reason for this is
the front arm becomes the pivot point between the
spindles and rear of the machine. With dominant
spring tension on the front arm, the suspension is basi-
cally contacting the snow from a point below the front
arm to the skis or the spindle pressure point. This
makes for a very short and darting machine on the
trail. This is especially true when decelerating and the
center of gravity is transferred forward.
A good method for adjusting the front spring tension
follows.
„
NOTE: On those models having a coil spring
over the front arm shock absorber, the spring ten-
sion should be set as soft as possible when oper-
ating on trails and in deep snow.
0729-662
FRONT ARM LIMITER STRAPS
Under no circumstances should the front arm limiter
strap be lengthened. If lengthened, it may cause shock
absorber travel problems.
The two limiter straps on AWS models can be short-
ened if desired. This adjustment must be made to suit
driving style and some test driving time. With the rear
arm in its present mounting location, no advantage has
been noted from changing the strap length. If the front
arm straps are shortened, the result will be more ski
pressure and aggressive steering.
SKI SHOCK ABSORBER SPRINGS
The shock absorber springs have been matched to the
shock valving and rear suspension. These springs are
the result of hours of testing and comparison riding
trying many different combinations of springs and
shocks. If there is a need to make changes, there are
several spring and shock sizes to choose from. While
making these changes, keep the following points in
mind.
Heavier Or Stiffer Springs
1. These will require shocks with more rebound con-
trol, or the front end will become like a pogo stick.
2. With stiffer springs, the front end will become
more aggressive in the corners as more weight will
be transferred to the skis when decelerating. Also,
more weight is transferred to the rear on accelera-
tion and can cause the rear shocks and spring to
bottom out.
3. If the springs are too stiff for general riding condi-
tions and style, the ride comfort is gone.
Spring Tension Too Soft
1. Front end bottoms out; hard on front end parts.
2. Less aggressive steering in corners on decelera-
tion, and less weight is transferred to the skis
because of softer springs.
3. Less weight gets transferred to rear of the machine
upon acceleration.
„
NOTE: When softening the ski springs, also
soften the rear to match entire suspension.
FRONT ARM SPRING TENSION TOO
STIFF
1. Slows machine down in loose snow.
2. Causes the machine to dart and dive as a result of
less track on the ground on deceleration.
! CAUTION
If the ski shock spring is adjusted too loose, the
spring retainer may fall out. If the spring is
adjusted beyond specification, the spring will
coil bind and spring adjuster damage will occur.