I still use friction DT shifters on my old road bike
Me too, Pete, and I actually prefer them! They still hold a place of honor on my rando bike and I won't be swapping them out anytime soon.
I have come to think it is the virtues of the traditional Rohloff twist-shifter that make it so devilishly hard to develop an alternative.
Basically, the Rohloff design is a simple pulley. Get away from that, and things get all sorts of complicated. If one goes with a cable spring-tensioned at one end, then there has to be a counter-spring for the opposite direction of travel. Then, you've introduced spring, ratchets, and pawls into the mix. Then, there's the dual-cable part of the design, which is handled most elegantly in the original twist-shift. I've been playing in the workshop and figured with a bit of creative work, one could make a coaxial housing that contained both cables...but why? Except for the second, parallel run of housing, the present system works reliably with conventional materials.
It'll be interesting to see what Mittelmeyer and others come up with -- and how well it works once developed and released.
Though the original works beautifully, there's a lot of pent-up demand for alternatives, judging by the volume of mail I receive, asking "are they here yet?". Alex Wetmore has been busily adapting Shimano Alfine/Nexus 8 hubs to trigger shifters (See:
http://alexwetmore.org/?p=559 ), but those hubs index at the lever rather than the hub, like Rohloff.
Best,
Dan.
