Locate the battery. Typically, on a Harley-Davidson 1200 Sportster, the battery is located below the seat. Open the seat to access the battery.
Find the positive (+) and negative (-) terminals. The positive terminal is usually marked with a red "+" symbol, and the negative terminal is usually marked with a black "-" symbol.
Attach the positive (red) jumper cable to the positive (+) terminal of the dead battery. Be careful not to touch the positive jumper cable to any metal surfaces, as this could cause a spark and potential an explosion.
Attach the negative (black) jumper cable to a good ground on the frame of the working vehicle. This could be a bare metal surface on the engine or frame, or a metal bolt or screw that is connected to the frame. Make sure the jumper cable is not touching the positive terminal or any other electrical components.
Attach the other positive (red) jumper cable to the positive (+) terminal of the good battery on the working vehicle.
Attach the other negative (black) jumper cable to the negative (-) terminal of the good battery on the working vehicle.
Start the working vehicle and let it run for a few minutes.** This will charge the dead battery and help to start the 2007 Harley-Davidson 1200 Sportster.
Try to start the 2007 Harley-Davidson 1200 Sportster. If it starts, remove the jumper cables in a reverse order(from the one above) and let it run for a few minutes to further charge the battery.
If the 2007 Harley-Davidson 1200 Sportster does not start, you may have a more serious electrical issue and should consult a professional mechanic.
