Want more out of your Polaris 850 Patriot? Order the MTNTK Performance Clutch Kit. This clutch kit will reduce belt temperatures, and improve up shift under power while providing crisp back shift characteristics. For the driven clutch is a full progressive custom helix and a heavier driven spring that makes for smooth power delivery and excellent belt life. In the drive clutch we include a spring that provides a slightly higher engagement without harshness. Improve responsiveness, track speed, and the overall feel of your Polaris 850 Patriot with the MTNTK Performance Clutch Kit. No fueling modifications required. Works with Stock Motor, exhaust, and components. Fits Axys 850 and Matryx 850 Mountain Sleds with 155,163,165 and 174 length tracks. Works with KHAOS and PRO-RMK Suspension package models.