[boredwitless]

Just in case it has any promise in replacing derailluers I've been following the Nuvinci developments. Because of that I was interested to see this review on a Nuvinci from the first production run: http://phil.veloblog.ch/post/7/333
Weight of 4.2 kg is clearly a big downer! Otherwise looks quite good; even disc compatible. I wonder if the weight could be somewhat reduced by using ceramic instead of steel for the balls?

 

[Bikinfoolferlife]

I doubt the 4.2 kgs could be much improved by changing the ball bearings! That is one heavy hub! While the CVT idea for a bike is appealing, that's just too dang heavy...