Cholla,

Even in four years, the 25 year deal may do you no good, especially where things are going in the US in terms of hippy tree-huggers hating on such fine inventions as 2-stroke motorcycles.

As was mentioned, the NSR250 was never sold in Canada. It was a Japanese market bike only by Honda. Unofficially it was brought into other countries as a grey bike by individual Honda Dealers.

You can bring it into the US as a competition use only vehicle. Only problem with that is you may never be able to get a road title once it's been tagged. Bringing it in as parts is doable, but can still get tricky. You don't want to bring the entire bike in the same crate broken down. Some inspectors will catch it. Then there is how to register it once you get it together. Many different ways to do that and many more ways to not do it.