Sigma Performance Slipper Clutches
and Race Specialities
Now with over 75 different clutches, our range incorporates many popular street bikes as well as the race applications that have made our name. Sigma slipper clutches are designed to allow easier downshifting on the road or track. Originally a pure race accessory our slipper clutches smooth gear changes for skilled riders and beginners alike by automatically and seamlessly disengaging the clutch whenever engine braking or rear wheel hop becomes an issue.
Riders report smoother performance on corner entry and exit, crisper shifting action and increased 'zip' from the motor as major improvements over the OEM slipper units. All clutches are supplied with alternative spring preload spacers to allow slip levels to be adjusted. Each clutch is individually designed using carefully chosen ramp angles with ball bearings for the smoothest performance possible on road or track. All are supplied with full instructions. Most models use standard springs and plates.