billet clutch mod This one piece clutch cam is a direct bolt in replacement for the OEM two piece unit. This part eliminates the "back torque limiter" which makes the clutch chatter when subjected to rapid take offs. This part is a must for Hayabusas that are drag raced, or subjected to heavy duty street riding. Clutch feel is vastly improved. With the one piece cam installed, the bike no longer has the back torque limiter and it is possible to lock up the rear wheel when down shifting. This is a race part and care must be taken. Comes with installation instructions.