Its always good to shed positive light on our hobby. Welcome. There is always more to learn about these bikes, considering there are almost infinite possibilities of how to go about motorizing a bicycle. If a motor can fit somewhere in or on the frame, and some sort of drive attached between the engine and frame, and the frame can safely handle the loads from the motor and drive train, everything is mounted properly and securely, and it can stop reliably, then it can, and most likely has, been done. I myself am working on a fully custom project that involves building my own wheels and a non-kit engine, in fact the entire bike is being built from the bare frame up. Most of the parts I'm using are not standard to bicycles. I am sure that there is much I will learn along the way, and I'm looking forward to it. My point is no matter how much you think you already know, it's always good to keep yourself open to learning more.