Hi!
The following has been tested:
Replaced / tested different plugs. Tested with different plug gap from
0,7-1,0mm
Ignition module gives a spark, but timing on high RPM is difficult to
check. ( Low RPM is OK)
Tested with different new battery pack 4,8-6 volt, 1100-1800mah.
Tested with two different carburetors. (Walboro)
Tested with different gasoline (ASPEN and 95 octane with 1:33 synth oil.)
Replaced all gasoline hoses / filters.
Tested different engine orientation.
Tested different ignition timing on magneto pickup.
Tested with start gas in carb. Does not help.
I tested with different needle settings. From 0,5 turn to 6 turn
open.