The application / use of capacitors in motorcycle electrical systems can be found in conventional ignition systems (using platinum), and CDI (Capacitor Discharge Ignition) CDI ignition with DC current (direct current) and CDI with AC current (back and forth). Figure 2 below shows the capacitor application on CDI current AC ignition system:
Based on the figure above, the capacitor in the CDI unit works to store a transient current (100 to 400 V) from a magnet that has been in advance by the diode when the SCR (Silicone Control Rectifier) is not active. After the gate G on the SCR is given a signal current for the ignition process, the SCR is active and transmits the electric current from the anode (A) to the cathode (K). With the functioning of the SCR, it causes the capacitor to discharge rapidly. Then the current flows into the primary coil of the ignition coil to produce a voltage of 100 to 400 volts as its own induced voltage.
As a result of self-induction of the primary coil, then induction occurs in the secondary coil with a voltage of 15 KV to 20 KV. The high voltage then flows into the spark plug in the form of spark jumps that will be used to burn the fuel and air mixture in the combustion chamber.
Example application of the use of capacitors on a motorcycle
Figure 2. Sample application of capacitor use on motorcycle
The use of capacitors on a motorcycle can easily be encountered on the flasher component of the turn signal.
Hopefully useful
Neat application of capacitor. It amazing to think that some parallel plates with voltage applied to the plate can store so much charge and instantly release them to make a turn signal flash in a motor cycle. Charging and discharging phenomena in a capacitor is really interesting. Will never forget from my physics class that C is directly proportional to the area of the plates and inversely proportional to the separation between them. A work is done by the applied voltage (battery) to move the charge from one plate to other. A capacitor is charged to a voltage of a battery and there is always a exponential discharge of that stored charge...and there comes the flash in a motorcycle.