From memory its about £200 for the pro twins mod including labour. I converted mine to one from these guys.
http://www.evoluzione.net/ uses the existing cables and is easy to fit. Does not shorten the throw by much though. Main feature is a non linear cam so throttle opening rate at low engine speed is reduced, but increased from the midway point in the rev range. So good for pootling round town, and pushing out of bends
Hybrid Mode
