Capacitor discharge ignition pressure inside the cylinder. Capacitor discharge ignition Capacitor discharge ignition (CDI) or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, turbine-powered aircraft, and some cars. It was originally developed to overcome the long charging times associated with high inductance coils used in inductive discharge ignition (IDI) systems, making the ignition system more suitable for high engine speeds (for small engines, racing engines and rotary engines). The capacitive-discharge ignition uses capacitor discharge current to the coil to fire the spark plugs. The history of the capacitor
Capacitor discharge ignition world efficiency to be only 35 to 38% when coil primary winding losses are included. Most CDI modules are generally of two types: The AC-CDI module obtains its electricity source solely from the alternating current produced by the alternator. The AC-CDI system is the most basic CDI system which is widely used in small engines. Note that not all small engine ignition systems are CDI. Some engines like older Briggs and Stratton use magneto ignition. The entire ignition system, coil and points, are under the magnetized flywheel. Another sort of ignition system commonly used on small off-road motorcycles in the