I have a 1990 Kawasaki 454 ltd (it is a 2 cylinder) over the winter I had the carbs off and cleaned and replaced the o-rings. when i first had it out this season it would run on 1 cylinder when i was driving so i would pull over and put the choke on and it would start running both again. so i put a tank of gas with seafoam carb cleaner in it and it worked fine for a day or two. now when i accelerate it bogs down at about 4000-5000 rpm. i checked the pet-cock screens and they are fine what else should i check?