B&S 22hp V-twin - Running rough, popping, sputtering

Greetings! Deere D130 riding mower with a B&S 22hp v-twin. Because of this issue, new carb, new ignition coils, adjusted valve clearance, replaced fuel filter. Cranks easily and will stay running, but still continues to run rough, coughs, sputters, & pops. I may be mistaken, but I didn't see an air/fuel mixture screw on the carb, so no adjustments made here. Any ideas, thoughts, recommendations will be greatly appreciated.