I'm chimming in a little late on this one but I have to say this.
It is so common to find a bikes carbs out of adjustment when they start running poorly. The carbs get gummed up a little which causes poor running, and then someone makes pilot screw adjustments to correct. This is the wrong way to correct the problem, if a bike was running great before it was put up for an extended period of time and then runs poorly after, you need to pull the carbs and clean them. The bike I bought had the same issue, it sat more than it was run and the pilots were cranked on too fix poor idle and so on. Started hard, one cylinder would fire late, popped like crazy. Pulled the carbs, cleaned them paying particular attention to the pilots and jets put them back in the bike and everything tuned right back into factory specs. Bike starts better, and runs better. Your bike is a 96, my money is on pulling the carbs, cleaning, and then setting to the 2-3/4 turns as recommended by jimmij900. This is probably a start point and you may find that the final position is closer to 2 if the bike is all stock. I know it's a PITA, but it has to be done, carb cleaner will not correct this by itself. Use carb cleaner and stabilizer to prevent this.
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