My dad and I both have the exact same bike: 2004 KDX220's with fmf gnarly pipe and turbine core II silencers. After our last outing in the woods, I laid my bike down and unfortunatly put a dent in my pipe (not very big...but noticable). I then started noticing a little "pinging" noise that my dads bike doesn't have. Now my bike is definately louder than my dads. Can a dent do this?? Or is my bike running too lean?? I never recall this noise before the dent...but it is possible. I just want to make sure I am not running too lean!!