2006-2008 Polaris Snowmobiles FS/FST Service Manual., Page 243Get this manual
Rear Suspension M-10 136
Rider weight with gear (lbs Under 100 100-150 150-200 200-250 250-300 300-350 Over 350 Suggested FRA Range (Lower number is softer) to 12 12 to to 12 12 to to 12 12 to to 5436109 Retainer insert Part Number
M-10 REAR SPRING PRELOAD
If FRA position alone does not allow the setup of the proper amount of sag, the center retainer of the rear track shock can be replaced with optional retainers to adjust the preload and change the sag
Optional Retainers
Retainer part Number 5135077 (stdon M10128) 5134923 5135080 (stdon M10136) Preload Least Middle Most Sag Most Middle Least
=Optional rear track middle spring retainer availableSee Optional Retainer Table