I rode the very small single speed coaster brake bike around the park this evening. It came back in very good shape and was easy to move along with the pedals. I am going to be actively searching for a multi speed bike. Preferably a steel frame mountain bike.

The simple no controller construction makes this drive system ideal for the DIY builder. At one point it went a little too fast and it is only 24v. It was scary at 36v.