Strong. Light. Disc brake compatible. Spirit disc cranks result from a sophisticated effort to develop the highest possible strength to weight ratio and pedalling performance in a unicycle crank.
Spirit disc cranks allow installation of a standard disc brake rotor (not included) to the right hand crank. This enables the rider to install a disc brake (see compatibility requirements below) and maintain an efficient pedalling stance, minimal weight, and the strongest possible wheel geometry. The rotor attachment is hardly noticeable for riders choosing not to use disc brakes. All cranks have double pedal holes for versatility.
7050 Aluminum (similar yield strength but tougher than 7075 Al)
Over 25% lighter than KH Moment cranks
Compatible with most hydraulic disc brakes (see compatibility requirements below)
Shaped to avoid ankle bone bashing and heel clipping
Shaped to optimize shifting for KH/Schlumpf geared hubs
Double pedal holes for versatility
Lengths (mm): 110/127, 117/137, 127/150, and 137/165
Weight: 378g (117/137) Disc rotor compatibility: 160 mm or larger, International Standard (IS) mount
• Disc brake with International Standard (IS) mount or IS adaptor.
• Brake caliper must clear 20 mm slot between disc rotor and inside face of crank. Tested on Magura Marta, Bengal Helix, Shimano BR-M575, and Shimano BR-M765 hydraulic disk brakes. Will fit most hydraulic disc brakes but not guaranteed to fit mechanical disk brakes.
• 160 mm or 180 mm (160 mm recommended)
• Requires IS brake mount on right fork blade or bearing housing, and 20 mm or narrower bearing housings (to ensure clearance of disk rotor bolts).
• Fits KH frames produced after June 2012. Other frames may require modifications. Older KH frames may require filing the outside face of the bearing housing to clear the disk rotor bolts. User frame modifications void the KH warranty.
• For frames without IS brake mounts, you can use the Nimbus 'd'brake' Disc Brake Mount to fit a disc brake.
• Standard 100 mm ISIS unicycle hub with 154 mm or longer axle.
Important Warning for Use of Spirit Cranks with KH/Schlumpf Geared Hub
KH/Schlumpf geared hubs contain a knurled (rough) bearing on one side. This knurled bearing surface acts as a brace against the tightened bearing housing when you are in high gear mode. Because crank-mount disc brakes apply braking force through the crank, braking in second gear may apply additional force to the knurled braking surface beyond that experienced during normal pedalling.
This additional force may increase the risk of slippage of the knurled surface. Slippage problems were not identified during testing. However, given the newness of this braking technology and wide range of users, we cannot guarantee that slippage of the knurled bearing will not occur for all users under all conditions. Slippage of the knurled bearing in the frame while riding in second gear will most likely lead to falls and could lead to possible injury.
Riders using Spirit Disc Cranks with KH/Schlumpf Hubs do so at their own risk. Check the tightness of bearing housings on a regular basis. If you experience slippage, do not use disc brakes with the KH/Schlumpf hub