An NSR250 was actually made to put out around 60hp. It was just the silly Japan laws that saw them put out the measley 40 something ponies.

At 60hp the NSR is hardley stressed, but that isn't to say it'll still be a reliable commuter tool. It is a race rep after all.

At 40hp the internals are barely being tickled, so you could pretty much ride it full volume all day.....allegedly!

You only really start giving the NSR motor grief when it gets to high 60's or 70hp. One of the major factors is the piston weight at the sort of rpm required to make top hp. That's when you need to start thinking about RS125 pistons, as their relative lack of weight gives the crank and all related parts a much easier time, even with engine speeds approaching 13,000rpm and beyond.