Delta Clutch was born in the racing scene as an irreplaceable tool. On track it has allowed the Malossi team mechanics to adjust automatic clutches of the scooters rapidly and accurately, depending on the type of track and the type of engine tuning. The perfect operation of this automatic device is fundamental to obtain a good start from standstill, and to exit from tight bends where the speed of the vehicle decreases. The advantages offered by these clutches when compared with the standard ones are huge, even for a road vehicle, because they allow sophisticated tune-ups for a very wide range of engine revs.105mm Clutch Requires 107mm Bell109mm Clutch can be used in OEM Stock Bell (Apex - DRR)Delta Clutch is Adjustable - Perfect for the Serious RacerFly Clutch is Non Adjustable - Stock to Mid-Race LevelsShoe Springs: Red = Race, Blue - Pro Race, Black - Extreme Race