There are two types of motorcycle ignitions. Most newer bikes have fully electronic ignitions, while older bikes have a simple contact point system. For the contact point ignition to work, the bike has a mechanical contact point, a rotating cam, a coil, and a spark plug. The system supplies a spark within the cylinder that jumps the gap in the spark plug electrodes. There are two circuits in the ignition system that will then come into play. While one circuit charges the coil, causing the contact points to close, a current travels to the plug cap and enters the plug through the electrode. The spark travels from one electrode to the ground electrode and the contact is made, causing the engine to fire up.