I have a raptor 250 And was wondering if I can do and engine swap for a 660 engine. If yes what will I need to modify. Or can I just do a clean swap. Thanks

 

I wouldn't recommend to do it. For starters, the 250 frame, suspension, and brakes cannot handle the power of the 660. You can always make it work, but it would not be anywhere close to a direct swap. It would take alot of time, welding, and fabrication skills to make it work, and would end up costing almost as much as you could buy a Raptor 660 for, and then you might end up with a hacked-up Raptor 250 that you can't hardly ride and that you can't sell because nobody would want it. That's how most of these projects end up that I see.

 

I agree completely. If you REALLY feel the need to put something else in there, look for a 250 4 stroke bike engine. Roughly the same size, probably 3x the HP.