Has anyone seen or done this ever? Seems as though a person could replace a swing-arm and forks on a dirtbike and you'd be in business. I already know that you have to move the chain out to match the sprocket. Axle for rear could be made out of a Honda 185 front axle (trike) with a sprocket welded to it. And a little brainstorming with my lathe, mill and tube bender it may be able to be done.
Any ideas?