Courtesy of TreeHugger.
Don’t be fooled by the elliptical frame, the built-in fender (mudguard) tailight, the chainless belt drive or the carbon fibre components. Oh, no. What is more intriguing here is the NuVinci CVP hub drive. NuVinci because it is a modern industrial adaptation of an idea that the inventor of the parachute and tank, Leonardo da Vinci himself apparently conceived, some 500 years ago. CVP because it stands for Constant Variable Planetary transmission.
Not that tells you much more. (It means it has no fixed gear ratios.) But let’s try this instead: “The NuVinci transmission uses a set of rotating balls between the input and output components of a transmission that tilt and vary the output speed of the transmission. Tilting the balls changes their contact diameters with the discs, which varies speed.� Still none the wiser? Watch the little demo video and all shall be revealed. At the moment all there is to see are some computer renderings. We trust they will materialise into real products. Fallbrook Technologies, who make the drive, say it can be scaled up to work on electric vehicles, agricultural equipment and wind turbines. Ellsworth who make the bikes, beginning at $3,000 USD, say they are first to put the NuVinci into a bicycle. Which they reckon is high on speed and stability whilst low on maintenance.
