A clutch lock-up system applies extra pressure to the clutch plates for positive engagement to prevent clutch slippage without increase of the lever pull effort. Great for seriously tuned engines or bikes with a wide wheel conversion. The Zodiac Posi-Lock kit features a ball-and-ramp system for an extremely positive engaging clutch and also changes the fulcrum point for reduced clutch lever effort. Fits straight into the stock clutch basket and behind the stock primary cover. Kit replaces the stock pressure plate, diaphragm spring and spring retainer. Fits all 1998 thru 1999 Evolution Big Twin and 1999 thru 2006 Twin Cam, except 2006 Dyna.