My 10-yr old girl wanted to build an electric car, and so we did. It's about the size of 2 power wheels, lightweight with PVC pipe and some wood framing for support. We have everything except the motor. I bought 2 power wheel motors, 24volt each at 30000rpms, 4 12v batteries, and a 24v wiring harness. We attached the motors to the rear wheels, and tested 1 of them by hooking 2 of the 12v batteries in series to 1 of the 24v motors through the 24v motor controller. The car was up on "jacks" when we tested it. The wheel spun great for about 30 seconds, then the motor smoked and started to flame a bit. I'm no engineer or mechanic, just a mom. Can anyone tell me what I'm doing wrong? My little peanut is really bummed. Any advice will be appreciated.