Too much fuel/air when you open throttle.
You picked up 4 kits from 4into1 yeh?
Replace everything in the carbs with the kit, except the needles. I recently purchased the same kits and had to file some of the main jet clip out with a round file so it slid onto the jet groove. Just do a little at a time and test it. It will still hold the old jet if you need to go back I found.
I too noticed the difference in emulsion tube holes, queried the forum but didn't get a resolution either way.
You should have replaced - slow jet, main jet, emulsion tube, the needle and seat and the air screw.
Set the floats around 23-24mm, is what I found after the clear tube test.
Setup fuel tank and carbs on the bench, carbs level as if they were sitting on the bike - turn the fuel on and make sure fuel isn't coming out the overflows. Eliminate float heights and correct needle and seat install.
Fit carbs back up to the bike, ensure that the airbox boots go well up over the rear carb inlet, and the clamps are tight.
Screw airscrews in softly until they wont go further, wind back out 1 full turn.
start the bike and warm it up, use the choke or whatever.
Once warm, Adjust the idle screw in/out to settle around 1200-1400 until the carbs are balanced (you'll get a steady 1200 idle then).
Give that a go - you can fine tune from there - do timing, then balance carbs and adjust choke stopper screw and air screw.
From there id recommend a dyno run, rather than plug chops for a quicker result and visibility of A/F through the range. See where its running rich/lean and adjust accordingly (larger/smaller small jet down low, needle clip mid range, larger/smaller main jet mid-high).
I know this goes against recommended using stock brass, but process of elimination will rule in or out.
