I just re-registered an old VW in Michigan that has a VIN that is 6 or 7 digits (something like that), they just fill in the rest of the space with leading zeroes. I am sure that IL probably does something similar, because some vehicles, especially older ones, do not have standardized VINs. ...
IL does have a way to do that--but only for vehicles that have previously been titled or registered, for custom vehicles that will meet
current roadworthiness standards (which bicycles can't meet), or for vehicles that are vintage and can be shown to meet roadworthiness standards at the time of their original manufacture.
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I have heard a reason that the law may be in dispute: a co-worker is considering getting a 150cc scooter, and knows someone at the local DMV. The law concerning motorcycle licensing in IL is being re-evaluated, apparently, and how this might cover motorized bicycles or not isn't yet known.
As it is in IL, motorcycles 150cc or above need a class-M license, 50cc to 149cc need a class-L license, and 49cc and under don't need any license at all. This is the reason that (according to the current reading) motorized bicycles under 50cc wouldn't need anything--no license because it's under the 49cc limit--and no registration or insurance, because you can't get them for a bicycle anyway.
The state is considering changing this to getting rid of the class-L and "unlicensed" categories, and requiring a class-M for a motorcycle of 1cc engine or above.
If this would change the legal standing of motor-bicycles, I don't know. I would think that they'd still need to specifically prohibit them. I'd wonder how they could charge you for riding an "unregistered motorcycle" if you're on a motorized bicycle and they insist that a motorized bicycle doesn't qualify as a motorcycle, and can't be titled and registered as one.
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