Schlumpf High Speed Drive (HSD), 30T – 75T Over Drive, 83mm, 170mm Cranks

If you want the ultimate pedal experience, look no further. This German made crankset bring your ebike to life with the ability to pedal at incredibly high speeds!  With the overdrive function, the 30T chainring turns into a 75T equivalent (250% increase!).  This new version features an integrated chainring/chain guard for simplicity and reliability. 

Bottom Bracket Size: 83mm

Crank Arm: Custom designed, square taper

Crank Length: 165mm

Comes with the Schlumpf crankset, crank arms, lockring, steel cone (for aluminum bottom bracket), shift buttons, custom crank bolts and lube. 

What is a Schlumpf drive?
Schlumpf is a company out of Switzerland that specializes in internal hubs. Unlike traditional internal hubs, the various Schlumpf drives all replace the standard bottom bracket (chainrings and cranks) and work in the front instead of the rear. The Schlumpf High Speed Drive is an internal gearing solution that uses planetary gears to increase the rotational speed of the chainring compared to the crank arms by 250% when engaged. Shifting is a breeze with simply a click of your heal on either side to shift.  When disengaged, the cranks are effectively locked to the 30-tooth sprocket. 

Installation

The Schlumpf Speed Drive requires some preparation of the bottom bracket with specialized tools. The bottom bracket needs to be chamfered at a 45-degree angle on each side. The drive is then held in place by a locking bolt.

We offer installation services as well. Typical installation time is 1.5 hours