Update:
Yesterday I could ride my gasser for about 3 hours and the result of the measures (see below) have helped to reduce fuel consumption from over 13 liters for 100kms to 9 liters. That means one tank should last for slightly over 100kms (62mls).
I can live with that. Spooge is too much still but I see no way to reduce it.
Changes I made:
NECW in clip 3
40 pilot jet instead of 42
GasGas GP cylinder head with 0.25mm less squish.
Bike runs well, had to reduce idle speed and ended at AS slighty less than 2 turns out. Temperature 66F/19C, Altitude 660ft/200m.
Unfortunately I and the bike suffer from a whiskey throttle. While I am waiting for a new handlebar, handlebar screws (bent), handlebar clamps, upper triple clamp, handguards, front and rear fenders I try to get rid of the pain in my body and especially elbow.