Good day to everyone here. I'm fairly new to this scoping stuff and wanted to ask your assistance. I've attempted to perform a secondary ignition capture on my old scooter (4 stroke, Capacitive discharge ignition system). It has a stalling problem while idling, also backfire after releasing the throttle at high speed. It also has a hard starting problem.
From what I've observed so far is that at idle, the firing line sometimes reach above 20 kilovolts and the spark line/burn time is short and has a downward slope. Comparing it to the waveform that I've seen on scannerdanner's channel (not the premium) and his book regarding secondary ignition waveform, it seems to be the plug wire and spark plug.
The plug wire was aftermarket and what I did was re-installed the OEM plug wire and there was less engine stall and the hard starting also improved. As for the spark plug, I haven't replaced it yet.
I have a rough idea of what is happening in the waveform and if anyone could explain further, I will be forever grateful.