BMP now has clutch kits for the rzr, the kit consists of a custom cut secondary helix, secondary spring. Primary spring with a set of supertip adjustable billet clutch weights. This will be the only clutch kit you need with the adjustability of the weights you can set this up for stock, and modified motors, large mud tires, high elevation, nitrous, etc. With clutch kit installed we had a 6 to 7 mph performance gain way better throttle response and better midrange pull eliminating the midrange bog at partial throttle. The price of the clutch kit is 338.00 but if you mention you seen this on prc forum you can get this kit at 300.00.