Sorry for posting that isn't about an NSR250, but does anyone know about the yamaha YZ250? I've got a crazy plan to do an engine conversion using YZ250 barrels, but I don't know about their use in a road bike.
So does anyone know how much power a tuned YZ250 makes, how wide the powerband is (1990's powervalve model). How long between changing rings etc. What RPMs they work at etc.
My crazy engine plan is to fit 3 YZ250 cylinders onto an NS400 engine, which will involve A LOT of expense - stroked crank (which will end up less than 68mm, but still workable), machined cases to fit larger stroke, adaptor plates to allow the barrels to fit, also some machine work on the cylinders, and modding the rear barrel to gain exhaust clearance. The cost is pretty high, so before commiting to it I'm trying to gather as much info as possible from anyone who knows about them.
Yes I am nuts before anyone asks!
But seriously any advice welcome....
Cheers, Mat.