Many scooters with chinese 2 or 4 stroke engines are mounted with different types of CDI. They are either AC type : Alternating current or DC type : Direct current.
To find an unlimited CDI, you must first identify the type of ignition you have. The easiest way is to do this, engine running, with an electric tester.
Place the probes on the pick up and the center ground and the low voltage arrival.To start, set the tester to AC : If it indicates between 30 and 80 volts, it is an AC CDI.
Otherwise, set the tester to DC and you will have to get between 12 and 15 volts.