Q. I am looking into buying a Honda VF400F. But I can't find a 33bhp kit or any legal way of restricting it. I have tried as many people and places as I can think of, including Honda dealerships and the like.
As far as I can see the only way is to do the DAS course (I have a restricted licence, recently passed) but doing the course again for a 600cc and tests are going to cost six times the price of any restriction kit.
A. Good news, you can get it restricted to the legal limit and for a lot less than a Direct Access course by getting it set up on a Fuchs dynometer. Fuchs dynos were developed with an eye to the now repealed French 100bhp law that took the figure from the gearbox sprocket.
So they have software with the transmission figures, engine type and capacity of pretty much every bike loaded up to allow them to work back from the rear wheel figure to the legal definition of 33bhp.
If your old bike doesn't feature all you need are the gearbox ratios and primary ratio too, and an operator will be able to load that up.
Dave Wood of DWR in Aylesbury deals with two or three a year and has also proved power outputs when owners have been stopped by a suspicious policeman.
“We use the DIN correction factor as that is the most conservative so we know the power output will be within limits. Depending on the bike, I'd reckon on about £100-150 all-in.”