julianthegypsy
Member
- Messages
- 4,309
- Location
- Cirencester
They are commercially available but horrendously expensive. My neighbour at work is a brilliant bicycle repair man and has fitted these before but more commonly he fits 8 or 11 speed sturmey archers. Yes, just like the three speed ones we had when we were kids but 11 speeds!Anyone else remember seeing CVT for bicycles on Tomorrow's World...? Never heard any more about it.
The main chainring was replaced by a disc carrying several small sprockets that were spring-loaded radially so with no load (ie not pedalling) they were forced to the perimeter of the disc. Once under way, as you loaded up by trying to accelerate or go uphill, the sprockets would compress their springs, reducing the effective diameter of the 'chainring' in the same way as dropping chainrings would. As the load reduced the sprockets moved back outwards, in effect changing up.
Probably answered a question that nobody asked and added 10Kg to the weight of a 10 Kg bike, but clever nonetheless
