Do a compression measurement. It's possible that the main seal on the air injector in the cilinderhead is leaking. Are you sure about the piston ring clearances? Cilinder in good condition?

Hey :) why a 3A battery instead of 4A standard for a Ditech? Do you have 7.5 and 10A fuses or 7.5 and 15A?

I do it in 30 min. You know little about that scooter.