This is far too broad to answer. Different states deal with it differently. Prior to 1980 MC manuf. Used different methods to number. Pre 1970 Harley's have motor vin number only. 1970-1981 has 9 digit matching motor and frame, and in 1982, the frame number is the "VIN" but the engine number, while different lengths, do match. After 1982 all VINs must be 17 digits in length. Some states number off of the frame only! Some states make the numbers match! If you title in a frame state and move to a matching state, (ex. Texas to Colorado) the matching state will VOID your title!!!
The real answer to your question is how to get paper work on the bike you have. The answer, start with DMV, be VERY nice, and patient, and ask for their help. It might be as easy as having the Sheriff do a certified vin inspection and pay a fee. Good luck.
One last thing, if the bike is hot, it WILL be seized! Remember, if it was too good to be true, it probably isn't, and people who support bike thieves deserve to have THEIR bikes stolen!
The real answer to your question is how to get paper work on the bike you have. The answer, start with DMV, be VERY nice, and patient, and ask for their help. It might be as easy as having the Sheriff do a certified vin inspection and pay a fee. Good luck.
One last thing, if the bike is hot, it WILL be seized! Remember, if it was too good to be true, it probably isn't, and people who support bike thieves deserve to have THEIR bikes stolen!