Re: Hello and help needed for father....
Meant to clarify what friction drive is. The motor shaft has a roller on it and some kind of lever mechanism brings the whole motor (roller) into contact with the wheel, either front or rear depending on the setup. The spinning roller makes the wheel go round and off you go. Simple. When you want to just pedal you move the lever and the roller is no longer in contact with the wheel, thus no drag. Some firction drive motors start with a pull cord and others start by pedaling the bike a bit and moving the lever so the roller engages with the wheel... give it gs and go. Usually mounting a friction drive kit is simple and straight forward. I think your dad might like this.
Someday when I grow up I will probably lose interest in toys with wheels, but until then...