SUZUKI VINSORCTIC CAT 500I. Improved acceleration and backshifting and maintains more consistent RPM under load conditions. A new secondary spring and roller weights developed specifically for this model. This clutch recalibration kit works well to help recover the dramatic losses resulting from oversized tires on this model. It can, however, be used with stock tire sizes as well for situations requiring better low speed/midrange response and performance (eg: mud/work). Use with stock tires may result in a minimal loss of top speed. There is no increase in engagement (stall) speed rpm so this kit still works well for low speed maneuverability like rock crawling, etc. It also helps restore power loss from higher elevations. This kit is designed specifically to fit the new style drive clutch on the 2008 750 Brute Force with the wide bushing. Improved acceleration and backshifting under load. Makes high range more useful at low speeds. Also offers flexibility to tune your clutch to rider preference and conditions. Two different primary springs are included to allow for preferred engagement rpm.