Bogged Down Low End Even After Adjusting Float Level - 78 CB750

Hi All!

I'm hoping someone can help me out... I'd love to understand my carbs better and would rather not have to take it to someone else to do. :-\

Here's what's up... after my 78 CB750F has always had a boggy low end since it's rebuild, I took the day to get into the carbs using this as my troubleshooting manual: http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html

I figured 100% that I was running too rich and the float level would be my culprit, so I pulled off the bowls to check it all out... and, too my surprise, the float levels were NOT too high, but actually low in 2,3 and 4(manual says a 14.5mm float height, and I was at like 16-18mm). So I thought, "ok, maybe I'm crappy at recognizing rich vs. lean," so I adjusted all 4 back to factory spec and bolted it all back together.

After starting back up, it's just as bad (maybe worse, but I didn't have it running for long too long). I'm bummed.

So, I took a little video after starting it up to show exactly what's happening: https://youtu.be/Iit1Btp0RQw
1st couple revs were gentle... After that I started giving it immediate full throttle.

Any help is hugely appreciated, I would love to understand these carbs better and fix this myself!

Thanks in advance!

PS. just for information sake: Keihin 42A Carbs with pod filters