The Polaris Rush line of snowmobiles introduced in 2010 were designed to dominate the whoops for snocross riders and hobby performance riders. Designed to absorb the harshest bumps and hard landings, RUSH’s bottomless suspension marked a significant change in Polaris’s performance sleds.
With a 599 cc Liberty liquid cooled 2-stroke engine under the hood and Cleanfire injection, the 2011 Polaris Rush 600 Pro-R is the newest model for Polaris performance riders. It uses Rocker Evans’ Piggyback shocks all around the front and Walker Evans’ Comp. Adj. rear track shocks. The hacksaw track is 15 x 121 x 1 inch. The seat is the lightweight freestyle, and windshields can be ordered in three heights, low, mid or tall.
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For more information see:
http://www.snowmobile.com/manufacturers/polaris/2011-polaris-800-rush-pror-preview-1168.html