The stock Hayabusa clutch is a three piece design which is meant to allow smoother downshifts.
The problem is that during hard acceleration the stock clutch with its lock up mechanism is grabby and chatters. This makes good launches almost impossible.
The Carpenter Racing Clutch Mod solves this problem. Our Clutch Mod Kit uses a billet aluminum - hard anodized ring that holds the lock up mechanism in a fixed position. No more having to weld up the clutch cam. Heavy duty clutch springs are included to prevent clutch slippage The Clutch Mod gives the rider improved clutch feel and control over the stock Hayabusa clutch.