Hi, i have on my XT600 a alloy supertrapp one piece pipe which connects to the header, it is stamped 4MPS-350 3, it is a 4inch end section with seven discs & end cap.The pipe fits well after i made a small bracket to secure the silencer to the top frame. My question is,is the pipe intended for the 84 XT ?, if not, what bike was the pipe for & how many discs is it meant to run ?