Let's be honest with ourselves:
This surging is a common issue of all these Honda engines.
The one in my Honda has the exact same problem and I have seen numerous threads started on the issue.
I bet this unit in question does it less when the fuel tank is full and more as the tank gets lower, just like mine.
In my instance, the carburetor is brand new, replaced by the Previous Owner less than a month before I bought it. All appears in order.
Unfortunately, I have yet to see a definitive answer for surging convincing enough to provoke me to tear apart a new carburetor. Carburetor is a French word for 'Don't touch it'. This adage has served me well for many decades. And usually the problem turned out not to be the carburetor in the first place!
If anyone has had this problem and knows definitively why they surge and how to fix it, please chime in.
If you did 2 different things at the same time and one of them got the problem fixed, please don't reply unless you can positively identify the cure.
It's almost like an engineering mystery novel. There is enough 'evidence' on this site, along with clues and red herrings.
And when we have that answer, make a sticky of it and stick it first in the Honda spot.