My buddy and I ride the rocky mountains. He has an AC454 and has experienced both ball joints crapping out, the top end of his engine loading up with oil and needing some work.We don't ride with anyone who owns a cat and just want to know if his machine is the exception to the AC durability. He has about 2100 miles and takes great care of the machine. He does not do any abusive riding. Any comments from others with cats would be greatly apreciated