I have a Luna 1000w kit with about 40 miles on it. Today when riding, it stopped working. The throttle stopped working and the rear wheel suddenly had resistance. The battery is full and there doesn't appear to be any cut wires or loose connections. The speedometer still gets power and lights up. When I twist the throttle the bike jerks forward for a second and there is a single clunk sound in the motor. If I try to just roll the bike forward there is a lot of resistance and vibration from the motor. If I disconnect the motor from the controller the wheel rolls freely. If I connect it back to the controller (even with the battery disconnected) it has resistance and becomes jerky again. Any ideas what this could be? A loose connection inside the wheel?