So I took the carbs off my 80 CX500C to clean them. After I got it back together it idled like crap. Took it for a ride and it never cleared up. Then I noticed that once in a while it would backfire at idle and when it did a puff of smoke came out of the right carb insulator right at the head. I unbolted the insulator and about 1 inch of the bottom of the o-ring was gone! I realized that when I attached the insulator that the o-ring must have come out of the groove at the bottom and got pinched off. about 1 inch of it must have got sucked through the valve and burned up in the cylinder. I'm waiting for new o-rings to arrive so I can put it back together. So what are the odds that the intake valve would be bent? Its just a small piece of rubber, but it had to have beat on it for a while before it made it into the combustion chamber. Would that bend a valve??