Motorcycle Repair: super b carb on 81 harley, pumper, electronic ignition

Question
is this a very streetable carb ? we are havin lean pop and backfiring and no power, the man we bought this bike from told us he went thrugh the carb but it still had this problem, is it best to just go to a super E or G ?

Answer
The one big difference between and superB and a superE carb is the super E has a pumper so when you turn on the gas it gives the motor a shot of fuel. The super G is to big for your bike.
Your carb might not be your problem. Do you have electronic ignition? Pull your spark plugs, what color are they?
Mike