I changed sensor today. The ceramic internal in the old was in several pieces. I got some very good measurements with the new sensor. I think my old measurements was wrong becauce of the sensor. I allways got hughe numbers on WOT before.

Maybe all the testing had destroyed it. All the backfires and black smoking etc etc.

It showed 10,5 on idle 11-12 on cruising and 12-14 on WOT. On sudden opening the throttle (VM 36), I had 1/2 secound 18, then 2-3 secounds around 15, before stabilizing on 12-14. I guess it is the lack of acceleration pump on the vm.

I agree. It is just the facination about exactly monitor whats going on and learn more about the combustion. After this jetting-process, I have learned a lot.

I am able to hear when it is lean or rich. And feel the heat from the engine to determine rich/lean conditions. A bit lean conditions feels like the engine is burning, rich - thumping. When you are between those stages - go down one size and enter the zone of burning, but not far from thumping. THats optimum.  I am back to feelings again, but it is good to confirm the jetting with the O2 meter.