unless the nut and bolt are reverse thread ... turning it counterclockwise will not tighten it. Normal thread counterclockwise will always loosen and the bolt will eventually just fall out.
Phil... the only thing different between the series of carbs is as Ray stated and that I know you already know is on the early standards the idle screw was on top. The later carbs on the bottom. But what I will say again, regardless of where the idle screw is clockwise tightens it and counterclockwise loosens it. I am beginning to think this might be a right brain vs. left brain thing. I tried to think about from top to bottom, right side vs. left side of the bike and it is still the same. I know I need to turn the screw clockwise to increase idle and counterclockwise to decrease it. I will leave it at that and hopefully the OP has it sorted out and doesn't have any thing else going on with his carbs. I have seen carbs out of synch actually do weird things when trying to set the idle. Same thing with vacuum leaks.
Phil... the only thing different between the series of carbs is as Ray stated and that I know you already know is on the early standards the idle screw was on top. The later carbs on the bottom. But what I will say again, regardless of where the idle screw is clockwise tightens it and counterclockwise loosens it. I am beginning to think this might be a right brain vs. left brain thing. I tried to think about from top to bottom, right side vs. left side of the bike and it is still the same. I know I need to turn the screw clockwise to increase idle and counterclockwise to decrease it. I will leave it at that and hopefully the OP has it sorted out and doesn't have any thing else going on with his carbs. I have seen carbs out of synch actually do weird things when trying to set the idle. Same thing with vacuum leaks.
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