I searched backfiring, but didn't find much help. My top end blew up, and the dealer replaced it under warranty. Before this happened, she ran perfect. Now, when at decel, it back fires nonstop, until I hit the gas. And it pops when trying to start it. Where do I begin? The dealer had no business messing with the carb, right? BTW, they had no idea what caused the piston rod to bend backwards.