Put VH short shots and arlen ness stage 2 big sucker on my 97 wide glide. Had cough on upper throttle range so I went from 175 main jet to a 180, 45 to 46 on the pilot, and did 2 flat #4 washers to raise the stock jet needle. And 2 turns out on air/fuel mixture screw. New battery, spark plugs and spark plug wires. This is the new spark plug after a 25 minute ride today. Clearly I moved a few things toward more fuel. I have some backfire thru the exhaust when im on the throttle pretty much in the 75% open range. What is the logical undo with the 3 adjustments I mistakenly tried to move at the same time.

 

I would remove washers from needle first and tweak adjustment screw, make a test run. If still to rich, next thing would be would be going back to a 45 slow. Would leave the 180 jet alone for now. Work on the low and the mid first. YD