The NSR125 uses a 16mm piston pin, so the piston for this kit won't fit the NSR250 crank. And I reckon I've hunted through every piston manufacturer's catalogue looking for one that will fit....Nada.
Lots of work required to get this to work.
Far from impossible as a one off, but would cost a fortune if you built a kit. Trust me, I've looked into just about every NSR125 big bore option with a view to putting it on the NSR250.
Cost is the only limiting factor. Oh, and my time of course
