Cleaned my carbs this weekend and when I put them back I had the same problem, turned out they were dirty and the air skew needed to be turned back in 1 half turn. (making them 1,5 turns out)
Mine are stock carbs with mainjet 270, pilot 25, airbox lid removed, +4 timing ricky stator plate & stator, fmf phatty headers & pipes, 1500ft elevation, BR9ES plugs and a 40 to 1 mix on Yamalube.