honda hawk 650 500 help

Hello: I'm Mac, live in Ohio, USA. I recently bought a 1978 Honda CB400A Hawk Hondamatic as a winter project / revival. The bike has only 1,790 miles on it and was stored inside since 1982 (the last year it was tagged). Lots of dust, mice nests, and rust everywhere. Engine spins easy. Missing...

hello, Iv been thinking about over the winter pulling my motor off and changing it for a bigger one. Im not sure what to do iv been looking in to a 500 or 650 but not sure if it will work with my 1980 Honda hawk frame. can anyone help me out? Iv looked around and dose'nt seem like anyone has...