Here is my take on the diy cd ignition setup using some cots parts and a 25cc homie.
I'm using a RPT C-500 coil and a VW electronic ignition conversion module with magnetic coil pickup.
Crank magnet is pressed into the original flywheel after cutting it down to minimum diameter.
I still need to get a short plug wire and remove the original C-500 rubber boot.
Works well with 4 -AA batteries.
Correction: 4 AA alkaline batteries work for a little while, switched over to 3S Li-Po, works better Found better unit at work update more later.