What is a CDI?

What is a CDI?

A CDI is an electronic ignition system that charges & discharges a capacitor to produce sparks at the spark plug.ignition cdi The spark plug creates combustion inside the engine which burns fuel & generates power.ignition cdi CDI systems are used on most modern motorcycles & cars.

Capacitors are similar to batteries in that they can store energy for a short period of time.ignition cdi What sets them apart from a battery is their ability to discharge all that energy at once, making them ideal for ignition systems. A capacitor discharges all of its energy in a fraction of a second enabling the spark to ignite the fuel/air mixture at the spark plug.

The basic CDI system consists of a trigger mechanism, coils & a box - often black - with capacitors inside.ignition cdi A black box is also known as a brain box, pulse pack or igniter box. The trigger tells the box when to fire, the box determines which of the coils with the capacitors will get zapped & wham! A spark goes to the spark plug. The black box may influence rev limit, timing advance & other variables but at the core it stores & discharges those capacitors to make sparks happen.

The two voltage inputs to the electronic CDI are a high AC voltage from the alternator & a low pulse DC voltage from the hall sensor or pulse generator.ignition cdi The high AC voltage is rectified to a DC current which charges a large capacitor. When the triggering circuit stops the operation of the sensor or pulse generator, the SCR (switch) in the ignition module connects the capacitor to the ignition coil primary. The quick discharge of the capacitor produces a high ignition output of many kilo-volts which is fed to the spark plug.

A drawback to traditional inductive systems is the long dwell time that is needed for the primary coil to saturate.ignition cdi A longer dwell time can result in uneven ignition & overheating of the spark plug. This is why many tuners favored a CDI system with its fast voltage rise & limited dwell time.

If you're experiencing ignition problems you should first check your stator & regulator/rectifier to see if they're the cause.ignition cdi You'll need a multimeter to test them. If the problem persists, you'll want to have a professional look at your ignition system if possible. A bad ignition system can seriously hurt your bike's performance. If yours is still under warranty, a dealership should be able to help. Getting the right parts from a reputable distributor will ensure your replacement ignition system is working properly & that your bike runs like new. Good luck! And remember if you have any questions or need assistance, don't hesitate to call us at 1-800-257-4833. You'll be glad you did. We have a wide selection of parts in stock to replace your worn out or defective components. We also offer a money back guarantee on all purchases. See our policies for details.

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