Topic: header diameters?

[beks82]

Hey guys I need some info. about the headers on a 76 f1.  my bike was missing the collector for the headers, and instead of buying another one I was thinking about making my own exhaust.  Anybody know the ID and OD for the header pipes of these bikes?

[KingCustomCycles.com]

CB750F has 35mm OD header tubes and the K models are 37mm.  I couldn't get ID or wall, but as you know, they are thin.