Bikeman performance clutch kits are designed to optimize performance for your machine. The high altitude machines are designed to have very quick throttle response in deep snow and boondocking, yet also have a strong pull up the mountain. These kits are developed and extensively tested in the Rocky Mountains of the USA and Canada. The flat land kits are developed to provide strong acceleration, quick throttle response, and great top speed. One key benefit to the BMP stage two kit is the smooth shift teflon washers for the driven clutch. No other company has this unique feature. The smooth shift teflon washers replaces the stock slider bushings under the spring. The smooth shift teflon washers will eliminate any friction produced from the stock bushing that must twist and push against the helix when the clutch is opening. Our custom helix was designed to accept these special washers with a stiffer driven clutch spring. The combination produces wicked throttle response and also more aggressive acceleration. Some models get oversize rollers, while other receive an adjustable pin kit. The primary spring is also changed to improve throttle response and acceleration. This is the first performance mod you should do to your E-Tec. Outstanding performance for your money! Please specify any other modifications done to your sled when ordering.