Nothing's going to bolt in without hacking the frame, and once you've done that you're buggered. The NSR motor is smaller than any 4-stroke... unless you feel like putting s Dream 50 motor in it! That's the whole point of the 2-stroke motor... power vs capacity vs size! Even a CRF250 motor, whilst narrow, is very tall. It will be nothing but trouble, but at least it's got a kick-start I suppose!

You may be able to squeeze a VT250 motor in there, but again, I would be amazed if you could get it, or in fact anything in without cutting some part of the frame.

Plenty of NSR's have been registered in the States, and there have been many posts on here in the past about ways to do it for various states. Personally, I would exhaust all other registration avenues before attempting to (a) register it as something it's not (i.e. a 4-stroke!), and (b) start hacking the frame about to perform a temporary and complicated engine swap.

I'd rather clone it with a VT250 that could then "disappear" than hack the frame about! What's the difference? It's going to be ilegal whatever you do unless you get it passed as an 90's NSR250 2-stroke.
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Andy.
NSR-WORLD.COM

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