I'm pretty sure this just is but though i'd post here to validate: the derailleur hanger on the chameleon seems to place the rear der. in a spot where it often whacks upwards against the chainstay, i think this also may be compounded by the chain tensioner which causes the chain to be at a more upward angle and then pulling the rear der. making it easier to hit the stay. Does this sound right, am i missing something? Wrapping the stay in rubber helps a lot but I'd like to think these parts would just mesh.