No offense, but you just realized these things are dangerous. You put a motor on a bicycle, how is that not dangerous? It's like strapping a rocket pack to your back and not figuring out it's dangerous until you crash. Me, I'll keep riding mine and trying to foresee anything that can go wrong to prevent it from happening. Even though it is my main mode of transportation, I have one more for the tinkering aspect.
Edit: I really should look at the date before posting.