Sounds interesting, I've seen some pretty weird contraptions put together from bicycles and motors.
A few weeks ago I was driving in the rain and jockeying around with an older man commuting on what looked like a touring bike (I always look at other bikes). He and I were in the right lane (stopped at a light) trying to turn right. He was behind me and passed on my right between the curb and my car, then proceeded four cars up to the light and he turned.
That really pissed me off as I hate to see other cyclist disobey traffic laws, and I just spent a good amount of time trying to get past him. Anyway, as I made the turn I was glad to see i could pass him (again) without trouble when he reached forward and yanked at something, then speed off at 30mph, sputtering engine and all.
Sears used to sell a motor you attached to the fork, I guess now adays you have to make them. can you post of pic?