Polaris 2001 High-Performance Snowmobile Service Manual (PN 9916690), Page 51Get this manual
GENERAL INFORMATION GENERAL INFORMATION Rear Suspension Shocks
You will need good quality gas shock, such as Fox or ArvinStock rear shock valving usually works well
Rear Suspension Springs
The front (center shock) suspension spring should be changed from stock to lighter rate depending on conditionsIf not changed, it will place too much pressure on the front of the rail, causing the sled to push, or tip up (high side)If the spring is too light, the sled could become looseStock rear springs work wellPolaris does offer different rates if you choose to change themSee Suspension Section for optional springs
Front Torque Arm Height