Hi Hardo - it likely means it was the 82nd bike of the production run, considering they made about 2700 KX250's in 83, that is pretty early in the line run. Often the first twenty or so bikes off the line go to the magazines for pre-testing, editorials and PR shots and are used by the Engineering Evaluation team to make sure the thing works as it should. Unlikely it is different to most other 83 KX250's - if it was a works bike, particularly Kawasaki, it would have completely different frame numbers to the production bikes.