I've always been intrigued by CVT systems for bicycles --- this bunch have made a very neat job of their take on the problem! Shame the YouTube discussions are (mainly) in Hungarian --- they should have called it the Rubike (I thank yew!). In the 1960's in Manchester, the engineering prof (Lightfoot, I think?) revealed he had gutted the transmission of a small saloon, substituting an extraordinary sleeved shaft, the halves of which were connected via a concentric spiral of heavy-duty copper wire, that alternately clamped and released. He asserted that this delivered smooth CV power to the rear axle, a claim which appeared manifestly incredible to this uncomprehending onlooker. It was with a mixture of disbelief and relief that I watched the improbable contrivance disappear down the road and successfully negotiate the corner ... Several CVT cars have appeared on the market in succeeding years, but none seems to have achieved commercial impact. People just don't seem to like them; why exactly should this be, I wonder? Would it be the same for bicycles? WFL On 9/23/10, Henry Baker <hbaker1@pipeline.com> wrote:

FYI -- Just when you thought that a 150-year-old invention couldn't be improved...

http://www.stringbike.com/

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