I suggest that you remove the aftermarket jets and needles, and put the original ones back in. Use the kit float valves, they just stop the fuel flow. I've had poor results with kit parts, they are pretty cheap (the rebuild kit is about the same price as a genuine Keihin float valve) but the jets and needles are not exact replacements for the OEM parts. I have "fixed" many fours with serious carb issues - poor starting, stumbling, flat spots, fouling plugs - just by putting in used original jets and needles.
Do clean the emulsion tubes, these get gummed up and that really affects the mixture. Clean all the cross holes using strands of fine copper wire like from extension cord cable.