Engine Trouble Interesting problem

[motorizedbikeguy]

So I took one of my bikes out for a spin today and it was backfiring and running strange. I took it home, let it cool, checked the top of the piston, re-torqued the head and took it for another spin. This time it was squealing really loud.. Now I'm scared. I took it back home, did a more thorough inspection and found something interesting. The problem was caused by the exhaust bracket being too far down (default exhaust) and being too tight. I did that last night thinking it would support the exhaust better if it was further down. What happened was the bracket was causing the exhaust to act like a lever, pulling the top of the cylinder and creating a gap at the base. I moved the bracket back towards the center, re-tightened everything and she's back to normal.

Moral of the story: If you use the exhaust bracket, make sure that it's around the middle of the exhaust and don't overtighten.