ok here is the story. i got a new piston kit to rebuild my top end and everything was going smoothly until the piston fell out of my hand when i was going to put it on the rod and left a very very small ding on the brim of the piston. nothing big. in thinking that it never touches anything it would be fine and i went ahead with the rebuild. i figured the rings rode the cylinder and that the piston never comes in contact with the top and it would be fine. well after getting it all back together it fired right up just fine and runs good except I'm hearing a clanking or small knocking noise now that is not normal or i never heard before. my 2 questions are could the dent be the cause of the noise ? and if not then what could be making this tapping noise. i went back and double checked the timing, the tensioner, the chain guides and everything and all was fine. pease help me out if you have an idea. thanks!
its a 2009 yz450f
Edited by motoxking989, February 28, 2015 - 04:07 PM.