Back story: Bought a 93 F2 of a guy from the hills of PA, nice guy low sided it coming to a stoplight, a little road rash on the bike but overall everything was ok. Wife finds out, makes him sell, I buy. Talking to the guy he said that he took it to the honda dealer and had the full service done. (plugs, wires, tune etc.) He didn't have any paperwork to prove this, but I can't find a reason not to the believe this.

Now my question, I live in the valley of VA, altitude somewhere around 1k feet above sea level. When I'm riding my bike around here and I do a quick decel my bike pops, kind of like a backfire but not so much. At first I was thinking it needed a jet kit considering it has a two brothers slip on and a K&N filter, but then I noticed that when I was on skyline drive (3k feet above the sea) and going to my moms in west by god virginia (2k to 3K feet) it doesn't do it. So now I'm thinking it could be set up for a higher altitude.

so how do I adjust the settings for the altitude? I know there is a screw on each carb, but how much do I need to turn and in what direction? Does anyone know the factory setting of the screws?