Im fairly sure I have a part throttle lean condition on my beater GS. At highway/ cruise rpm of around 2500-3000, Im getting a very subtle random misfire. Feels like a intermittent hesitation. Plugs had about 800 miles on them and came out super clean with almost no color on them. The porcelain had a pinkish hue but I chalked that up to the additives in the fuel (?). I threw a new set of plugs in it just for kicks. Original 7040240 carb was gone through by a very reputable shop. Shafts were re-bushed. Carb runs well otherwise. Secondary rods are brass with no stamp and look to be similar in shape to an AX or AU rod. Im going to finally pick up a portable wideband O2 kit this week and a tailpipe clamp to verify my suspicions So lets assume Im correct and the carb is running lean at cruise, what the best way to go about richening it up? Would installing an APT screw be the path of least resistance?