carb screw IN , really dont recall direction , just make sure in counting turns so can easily be put back as it was

yes the leaner the fuel air ratio the better performance the bike will get but itll run hotter , to lean is very very bad , thats why they set em rich WAY to rich causes no problems except fouling plugs

fuel cap has a baffle on it , put hairtie on it to keep it from seeling tightly to stop vaporlock , but thats not your problem

and yes instead of a gauge I just do it by "Feel" , tight/lossen untill when VIGORUSLY rocking the individual valves they barely tick