In this video they describe how the shifting will work:
https://www.youtube.com/...amp;feature=youtu.be


It's a pretty interesting idea. Lots of people have tried to improve on the mechanical efficiency of a traditional chain drive system for a long time without practical success. It's really very efficient to begin with. I'd be interested in seeing an independent test. How do they deal with the concentric shaft friction? Are there roller bearings in there too?

I'll also be interested in how fast that shifting can happen. To make that work they are going to have to get an encoder in there somewhere. Maybe in the parabolic shifting channel it will be able to span the whole range of gears within one revolution, but that servo motor will have to be awfully fast. Like really fast.

I wonder how much this will cost....

Your idea about incorporating watch bearings into a conventional chain is interesting, but they would have to be such small diameters, I wonder if hertz stresses would be a deal killer, even at the relatively low loads involved in cycling.

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Ed O'Malley
www.VeloVetta.com
Founder of VeloVetta Cycling Shoes
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