There will always be a loop hole of some sort. Just need to take the time to find it is all.
Trust me, the DMV's, DOT, etc. have a lot more problems on their hands then a couple grey market bikes coming through the system each year.
With the influx of "home made" motorcycles on the upswing, the systems have already tried to put controls on that. This wasn't to go after the every day Joe who wants to build a custom bike, but more for the shop that is turning out 10 or so a year.
As for the "loop holes" Trust me, if you or anyone on this forum knows them, I am sure the people in the government who even care about this know about them. They probably don't have a huge issue with a couple bikes here and there coming through the system. It's the person who tries to title/reg 10 or 20 bikes every couple months that they take issue with.
I remember back in the 98 when I was looking into my first NSR. All the talk about police seizing registered NSRs off the street, out of people homes, etc. Heard plenty of stories about it, but never once did I hear from someone who actually had it done. Hell, I even had email discussions with someone from NHTSA who could have done something about me registering a NSR. Never a knock at my door, or a cop in my rear view. Now if I was doing a trailer load of bikes at a time and bringing in shipments ever other week? Sure I am positive I would get a visit.
So if your trying to register a bike on your own, don't worry, the secret service are not going to show up at your door, your bike isn't going to be taken from you by a group of SWAT, and your not going to be taken to CUBA to rote in a jail cell cause your our nations top criminal.
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Charles Gallant