I have some performance issues with my LX150. It was knocked over in 2009 and since then it makes a noise like something is banging around. It kind of sounds like an old car when going over bumps. It also does not perform as well as it used to. I bought the scooter new early in 2009 but after it got knocked over, it is very slow now and takes off very slow as well. I have taken it to several shops and they all haven't been able to solve the problem. One shop found that the air filter was caked with oil so they cleaned it and also they checked the carb and nothing seemed out of place, everything checked out good. They also checked the clutch and cleaned off glazing on the pads but that didn't solve the problem either. The checked the autochoke which was fine and even swapped out my carb with a known good one and that still didn't completely solve the problem. Is it possible that it could be that my valves are not in spec or functioning properly, possibly due to the knock over? Any adivce would be much appreciated.