Snowmobile Polaris (2006 year). Manual - part 55

11.2

REAR SUSPENSION

REAR SUSPENSION 
SPECIFICATIONS

MOUNTING TORQUE SPECIFICATIONS

3/8”top shock mounting bolts........28-30 ft. lbs. (39 - 41 Nm)

3/8”suspension mounting bolts....35 - 40 ft. lbs. (49 - 55 Nm)

7/16” suspension mounting bolts...55 - 60 ft. lbs. (76 - 83 Nm)

Shock rod bolts(do not over torque)*Shock rods must pivot 
freely after torquing...................................12 ft. lbs. (17 Nm)

REAR SUSPENSION 
OPERATION

OPERATION

The primary function of the rear suspension is to provide a 
comfortable ride in all types of riding conditions. It separates 
the rider from the ground, while allowing for complete vehicle 
control. The rear suspension also must provide weight transfer 
and maintain track tension.

The rear suspension has many adjustable features for fine 
tuning to achieve optimum comfort. The suspension can be 
adjusted to suit rider preference and deliver excellent 
performance for a given set of conditions. It should be noted, 
however, that suspension adjustments involve a compromise 
or trade off. A machine set up to perform well in the moguls 
would not suit the preference of a groomed trail rider.

WEIGHT TRANSFER

The shifting of weight from the skis to the track is called 
weight transfer. As engine torque is applied to the drive axle 
the torque is transferred to the track, pulling it forward. This 
energy also tries to pull the suspension forward. The front 
torque arm reacts to this force by pushing down on the front of 
the track, in effect applying more weight to the front of the 
track and reducing the weight on the skis. It is important to 
note that energy used to lift the front of the machine is not 
available to push the vehicle forward.

Changing the angle of the front torque arm changes the 
suspension's reaction to the force. Adjusting the length of the 
limiter strap will change the front torque arm angle. 
Shortening the strap limits the extension of the front of the 
suspension; reducing the angle of the torque arm and 
increasing ski pressure during acceleration. Lengthening the 
strap allows the front of the suspension to extend further; 

increasing the angle of the torque arm and decreasing ski 
pressure during acceleration. Limiter strap adjustment has a 
great affect on weight transfer. Limiter straps only affect 
acceleration. It is important to check track tension whenever 
limiter strap length is changed. 

Front track shock spring preload also affects weight transfer. 
A stiffer spring and/or more preload on the spring transfers 
more weight to the track. A softer spring and/or less preload 
keeps more weight on the skis. Keep your riding application 
in mind when choosing springs and setting spring preload. 
Soft springs/preload will increase ski pressure, but may 
bottom out. Stiff springs/preload will provide more track 
pressure (reduced ski pressure), but may result in a less 
comfortable ride

During acceleration, the rear of the suspension will compress 
and the IFS will extend, pivoting the machine about the front 
torque arm. Because of this pivoting effect, rear spring and 
spring preload also have some effect on weight transfer. Softer 
rear springs, or less preload, allow more weight transfer to the 
track and reduce ski pressure. Stiffer rear springs, or increased 
preload, allow less weight transfer to the track and increase ski 
pressure. The main function of the rear torque arm is to 
support the weight of the vehicle and rider, as well as to 
provide enough travel to absorb bumps and jumps.

Shock valving also has an effect on weight transfer. Refer to 
shock tuning information in this chapter. Scissor stops also 
affect weight transfer. See scissor stop information also in this 
chapter.

Rear Scissor blocks also have a big effect on weight transfer.

 

see “SCISSOR STOP ADJUSTMENTS” on page 11.4.

SUSPENSION COUPLING

On all Polaris snowmobile rear suspensions, there are two 
torque arms that control the movement of the rail beam. Prior 
to the advent of suspension coupling, these torque arms could 
move independently of each other. Rear suspension coupling 
links the movement of the front and rear torque arms to each 
other.

The front rear scissor stop (FRSS) couples the movement of 
the front torque arm with the rear torque arm and limits the 
amount of independence between the movement of the front 
torque arm and the rear torque arm.

When hitting a bump, the front torque arm starts to compress. 
The FRSS links that movement to the rear torque arm, causing 
it to compress and raise the rear suspension up as one, 
allowing the suspension to hit the bump only once and 

11.3

REAR SUSPENSION

eliminating kickback. The factory setting are usually adequate 
for all riders in all conditions.

The rear rear scissor stop (RRSS) couples the movement o the 
rear torque arm with the front torque arm and limits the 
amount of independent movement between the rear torque arm 
and the front torque arm.

Adjusting the RRSS either allows more weight to transfer to 
the rear for more traction, or allows less weight to transfer to 
the rear, resulting in improved cornering performance. And 
adjustment dot is located on the RRSS. This dot id at the 
higher end of the scissor stop.

Moving the RRSS to a higher position will reduce weight 
transfer, improve chatter bump ride and improve cornering 
performance.

REAR TORSION SPRING TENSION 
ADJUSTMENT

Rear spring tension adjustments are made by rotating the 
eccentric spring block. The block provides three spring tension 
positions. This adjustment is easier if the long spring leg is 
lifted over the roller and replaced after the block is properly 
positioned. Always maintain equal adjustment on both sides.

Torsion springs are much like coil springs, although shaped 
differently. The rate of the torsion spring is controlled by the 
wire diameter of the spring, and the number of coils. Pre-load 
is controlled by the free opening angle. see “TORSION 
SPRING ADJUSTMENT” on page 11.5.

REAR SUSPENSION 
ADJUSTMENTS AND SETTINGS

REAR SUSPENSION ADJUSTMENT 
PROCEDURES

It is a good idea to have customers break the suspension in for 
approximately 150 miles (240 km) before fine tuning 
adjustments are made.

All settings will vary from rider to rider, depending on rider 
weight, vehicle speed, riding style, and trail conditions. We 
recommend starting with factory settings and then customizing 
each adjustment individually to suit rider preference. The 
machine should be methodically tested under the same 
conditions after each adjustment (trail and snow conditions, 
vehicle speed, riding position, etc.) until a satisfactory ride is 
achieved. Adjustments should be made to one area at a time, in 
order to properly evaluate the change.

The purpose of the front rear scissor stop (FRSS) is to control 
the bump attitude of the rear suspension. As the front torque 
arm (FTA) hits the bump, it forces the rear scissor to collapse a 
predetermined amount, depending on the FRSS block position.

This accomplishes two important things, it allows a lighter 
spring rate on the FTA because it can borrow spring rate from 
the rear torsion springs; and it prepares the rear portion of the 
suspension for the bump, reducing secondary kick back.

The FRSS is made of a resilient material allowing smooth 
action and preventing any suspension component damage.

This unique feature is applied to the EDGE rear suspensions.

11.4

REAR SUSPENSION

SETTING REAR SUSPENSION RIDE 
HEIGHT

1.

To set up the rear suspension torsion spring preload,
measure the distance between the ground and rear bumper
with out the rider on the seat and the suspension at full
extension. This can be achieved by lifting the rear of the
machine so that the suspension is off the ground and
carefully setting the machine down. Write this down as
measurement “X”.

2.

Have the rider in full gear drop down on the seat, work the
suspension slightly by bouncing up and down and sit in the
seated riding position. With the rider in the seated position
measure from the ground to the bumper in the same spot
as you did for measurement “X” and write it down as
measurement “Y”.

3.

To determine the correct ride height, subtract
measurement X from measurement Y. (X - Y = ride
height).

4.

The ideal ride height is:

• IQ Fusion (700/900) = 2” (5cm)

• IQ Fusion (600) = 4-5”(10-13cm)

• IQ RMK = 5” (13cm)

• IQ M-10 = 3-4” (8-10cm)

• Switchback = 5” (13cm)

• EDGE RMK/EDGE = 4” (10cm)

• EDGE M-10 = 3-5” (8-13cm)

• Widetrak = 1.5” (4cm)

5.

Adjust for the desired ride height by rotating the torsion
spring cams located on the rear of the torsion spring. 

If the rear suspension ride height can not be adjusted to the 
correct dimension, optional torsion springs may be required. 
This is only an initial setup, and final spring preload may vary 

based on rider preference and riding conditions.

SCISSOR STOP ADJUSTMENTS

The RRSS controls weight transfer from the rear suspension 
to the skis. It also influences the stiffness of the ride by 
controlling the amount of coupling action between the front 
and rear torque arms. To decrease weight transfer, the RRSS 
should be set in the high position.

The RRSS can be totally removed for maximum weight 
transfer. However, unless the torsion springs and rear shock 
valving are changed, the ride will be compromised. Always 
maintain equal adjustment on both sides.

To adjust the scissor stops place the scissor tool onto the 
scissor block and turn to the desired position. Ensure that the 
rear scissor stop face is square with the face of the scissor arm 
to ensure complete contact.

X

Y

ROTATE

11.5

REAR SUSPENSION

The dot is an indicator of 
the HIGH position. The 
sides are the LOW 
position and the bottom 
is the MEDUIUM 
position. 

FRONT TORQUE 
ARM LIMITER 
STRAP 
ADJUSTMENT

One method of changing ski-to-snow pressure is to change the 
length of the front torque arm limiter straps. The limiter strap 
is normally mounted in the fully extended position. Both 
limiter straps must be adjusted evenly and remain equal in 
length to avoid improper Hi-Fax and track wear.

• Lengthening the straps decreases ski pressure under 

acceleration.

• Shortening the straps increases ski pressure under 

acceleration.

RMK Set up Recommendations for Optimum Performance

• DEEP POWDER SNOW:FTA in LOW position for 

maximum lift and flotation

• POWDER-HARDPACK:FTA in STANDARD position 

for overall handling and speed over snow.

• HARDPACK: FTA in HIGH position for increased 

control and less transfer.

TORSION SPRING ADJUSTMENT

To adjust the rear torsion spring, rotate the adjuster cam to the 
desired adjustment. The cam has three sides, LOW, MEDIUM 
and HIGH. 

HIGH

LOW

LOW

MEDIUM

LOW

MED

HIGH