These cranks were also combined with a schlumpf hub to create a geared unicycle.
The design allowed the crank caps to be pushed with the foot, one to change up, the other to change down a gear.
http://unicycle.co.uk/shop/schlumpf.htm?id=734
@olmasters started
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These cranks were also combined with a schlumpf hub to create a geared unicycle.
The design allowed the crank caps to be pushed with the foot, one to change up, the other to change down a gear.
http://unicycle.co.uk/shop/schlumpf.htm?id=734