suggestions on where to start w/ jetting

[Dr89]

im nearing the end of my 300ex "project" and need to know where to start with the jetting so i can finish this thing up. i just put on it an hmf/white bros. full exhaust and a twin air filter with drilled air box lid. im alright at jetting i just dont know where a good starting point is with those mods. all i had on hand was a 125 main and a 138 main. with the 138 in it now it idles and revs fine until 3/4 to full throttle when it starts to cut out, and on deceleration it makes a loud, sharp popping sound. that made me think its still running lean, but with only a pipe and filter i figured 138 would be much to big. just lemme know what you think i should start at, main and pilot (thought the pilot might solve my backfiring problem?) im in central kentucky but dont really know my elevation.

[bwamos]

Start with a:

132 Main
Needle clip in 4th slot (Slot 1 is on the blunt end of the needle)
Air/Fuel screw (bottom front of carb) 2-1/2 turns out from seated. Stock pilot should be fine with your mods.

This is for 500ft-2000ft elevation at normal tempuratures/humidity.

Should be pretty close.

[Dr89]

alright i'll try that. i dont have a manuel though and i mix up the air/fuel and idle screw. is the air/fuel mixture the small flat head gold one actually on the carb, or the larger silver flat head connected to a hose off to side?

[bwamos]

Air/Fuel screw is the small brass screw on the bottom of the bowl toward the front of the carb. The idle speed screw is the larger one (mounted on a standoff bracket on the 300ex)

[Dr89]

yea thats what i orignally thought but i couldnt remember exactly, i had the carb apart today and now i cant figure out how to adjust the needle. is it right below the float...or does it have somethin to do with that little gold flat head screw tucked down in the middle of the carb? dang this would be easier with a manual!

[Dr89]

nevermind i found the needle and adjusted it...its runnin better already, just gotta wait for the 132 to come in and i should be good to go! thanks man