Polaris 550 Shift 136 Owner's Manual For Maintenance And Safety page 38

THE PERFECT FIT
IQ Rear Suspension Adjustments
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.
There are two types of rear suspension coupling.
Front To Rear Coupling and the Front Rear Scissor Stop
(FRSS)
The front rear scissor stop (FRSS) couples the movement of the front
torque arm with the rear torque arm and limits the amount of indepen-
dence 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 reducing kickback.
The factory setting is usually adequate for all riders and conditions.
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