Why no R7s at the TT?

The Lightweight TT is replaced by the Supertwins TT this year which mean R7s can race. But it looks like none are going to… » You’d have thought the R7 would be a shoo-in the new Supertwins TT class, which allows twins up to 700cc. There are a couple of problems though. Firstly, shortages meant teams couldn’t get bikes early enough, and secondly, the regulations prevent the kind of tuning needed to get the R7 up to the levels of well-sorted Kawasaki ER-6S. ‘The problem is that you can’t bore the throttle bodies,’ says experienced TT racer Dave Hewson, ‘and until you do that, you can’t get any power out of them.’ Standard R7s make 70bhp, which is 20bhp short of the competition. ‘As far as I know, no-one is racing an R7 at the TT,’ says Dave.

The Aprilia RS660, on the other hand, is a simpler proposition, which is why Dave is racing that instead. ‘With a pipe and a map it makes 95bhp at the wheel with no ram air. We’ve done nothing to the engine. It’s about right for the weight limit too so you don’t have to do much there either.’ My old engine [a Cf-moto copy of an ER-6] had trick rods, JE pistons, a flowed head, different cams and springs… and lots more. And made 92bhp.’