Bonneville America Forums Forums Technical Forums Exhaust popping

You should have more of a rumble on decel with less restrictive pipes. Excessive popping or backfire can indicate a lean condition but it can also indicate an exhaust leak. If you put less restrictive pipes on with no jetting or adjustments you are probably lean. If the stock air box is still in place and not changed you can probably go up a size on the main (depending how open your pipes are you may not need to) and adjust the pilot screw.