The CDI, or capacitor discharge ignition, is a crucial part of the electrical system that helps regulate the spark plug. If the CDI is damaged, it can cause engine problems like sputtering or difficulty starting. It’s typically connected to the stator coil or the battery, and then to the plug coil and spark plug. This is the most common engine electrical system on motorcycles. However, some models like the Suzuki TXR 150 combine the coil plug with the CDI.
As a mechanic, I’ve encountered two types of CDI systems on motorcycles. The first type works with the stator coil, while the second type needs a battery to produce the spark at the plug. So, the answer to the question “Does the CDI need a battery?” is both “yes” and “no.”
Why won’t my motorcycle start when the battery is fully charged and connected?
It’s because your motorcycle has lost its power source. It doesn’t draw electricity from the starter coil to start, so it needs another source like a battery. The magnet inside the coil doesn’t have a starter coil (just a single coil), only multiple coils called fuel coils that charge the battery and turn on the lights. Without an electrical source, the engine can’t start.