I replaced my Two Brothers slip ons with stock exhaust with the baffles completely removed and the bike has started to pop like crazy during engine braking. To me this indicates a lean to good air fuel ratio. Could the stock exhausts actually flow better than the aftermarket "racing exhaust"? Also if anyone is interested the bike sounds a lot quieter at Idle but I seem to be setting off more car alarms than usual

 

I highly doubt the stock exhaust flow more than the tbr cans. Its hard to flow more than a tube with a straight line out (ie tbr). Even without the baffles the stock exhaust is a labyrinth of blockades. I'm not saying it didn't change things I just think its the other way around slightly rich. Both lean and rich conditions can cause backfires but on superhawks when lean the carbs miss every now and then sometimes called a lean backfire or hiccup its very obvious when it happens so if its just exhaust backfiring I would say to rich.