Going Electric
A motor is designed to spin rather than to be spun. So, when connected to a charged battery, it will want to draw power from the battery to turn the bike wheel. To prevent electricity from flowing the wrong way, I inserted a diode between the motor and the battery. A diode directs a current in only one direction, from the anode to the cathode; in my circuit, the anode faced the positive terminal of the motor, while the cathode faced the battery's positive terminal. I wrapped the ends of the diode around the motor's exposed wire and an alligator-clip-tipped test lead, which fastens to the battery, and insulated the connections with electrical tape. Then I wired the motor's negative lead directly to the negative terminal of the battery.