Carb Spitting

When I warm up my kz1000st 1979 with the choke on full it revs like crazy, so I dont choke it as much but then you can hear the at least one if not 2 of the carbs spitting or missing. This creates popping sounds out of the exhaust. I even seen little white puffs of ?smoke? at the intake side of the carb not hte airbox side. I tried to make sure the clamps were tight and they seem to be. Also the bike bogs down and has popping sound under acceleration at around 70kmh or at about 5-6000 rpm. Currently there is no air filter and the popping sound goes away during normal city driving or idle.:S

check the intake and exhaust valve clearance. If u cant fit a .oo2 feeler gauge under any lobes, youve found the problem.

Check valve lash but am inclined to think you may have damaged carb intake boots. Look closely for signs of cracking. Spray with WD40 and see if problem temporarily goes away.