UPDATE:
https://streamable.com/gmwv4
I finally got the carbs out, took it a part and it was clean. BUT, the idle mixture screws were ridiculously backed out, something like 5 or 6 turns. I reset them to 2.5 turns out.
Does this mean at idle I was running very rich, thus the occasional bog at idle?
I also replaced the main jets, pilot jets, and shimmed the needle with this kit:
https://www.ebay.com/itm/08-12-Kawas...72.m2749.l2649
(2 one size larger Pilot Jets (#40), a set of 2 two sizes large Main Jets (#102) and one needle shim for each carburetor)
The original jets were clean, I could see through the holes, but were a little darkened at the tips.
Exhaust was also changed to a slip-on leo vince
Looks like my lean spot at 2k rpm is almost gone and idles nicely; took it out tonight and it performed flawlessly. I still get quite a bit of pop, and backfire flames when I abruptly close the throttle. Normal or should I back out the idle mixture screws again to 3 turns.