I acquired a used pro circuit platinum for the cr250, it was ridiculous heavy and obviously did not resonate anything but spooge. I believe it was a quarter inch from front to back! Got the fire going, legal size of course, 20 some inches, put the pipe in till it was good and red, it never got yellow. I could see the spooge finally burning off, a couple of hours tops. After it cooled, I put some big nuts in the pipe and shook it, rinsed and repeated till all the carbon fell out. Then it got duct taped, filled with water and carefully placed in the freezer over night, lazy dent removal 101. Factory new pipe. I should start a service for a hundred bucks a pipe? I think there is a guy cheaper on the net. Vintage Bob