What is the outside diameter measurement of the Yosh RS2 full system header pipe and the 400E pipe? I have a 400S and was wondering how much larger the other two header pipes are. Mine measures 1 1/2" O.D. The only other 400 I have seen to check was a Quad with the 400 c.c. motor in it. It had the keihin carb and its header pipe was 1 1/2" O.D. I don't know if the quads share the same exhaust system as the 400E.