Ian, in the draft guidance notes for VHIs, they are suggesting that engine swaps will be allowed if no more than a 15% power to weight increase over original.
This is mostly car based of course and they say that bikes may differ...but Norton used identical rolling chassis from the 17 bhp Model 50 right up to the 55 bhp Atlas....and in fact changing a 350 engine to a 500 would fall foul of the guidlines.
What about chops and customs that were created over 40 years ago with altered frames, raked forks etc. The WHOLE bike has been together for 40+ years. How would that work?
