Has anyone every replaced their CDI with an aftermarket unit? Good, bad?
Unless you are referring to rather old two stroke bikes, I think your use of the term CDI may have been accidental, as the 919 does not have Capacitor Discharge Ignition. Past that, for decades now, certainly by the 90s, the OEM motorcycle ignitions have been decent or better. Also, aside from the crank trigger, coils and plugs, the system is highly integrated with the ECU. Are you experiencing problems that you or someone else has attributed to being non spark plug ignition related?