Ok it i got it.
It is the capacitor in cdi unit in which the charge from generator coil in the magneto is stored and then just before the point of ignition the charge is released from capacitor in to the primary side of ignition coil which is a step up transformer.
Here is wiki excerpt
In a CDI system, acharging circuit*charges a high voltagecapacitor, and at the instant of ignition the system stops charging the capacitor, allowing the capacitor to discharge its output to the ignition coil before reaching the spark plug
If genuine cdi also produces less spark then it means sari game cg 125 ka ignition coil ma ha.. Try that.
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