four into four exhaust system 1981 DOHC custom special!

Posted by Gearbox on
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/four-into-four-exhaust-system-1981-DOHC-custom-special-tp458128.html

I have looked at a number of downpipes for the CB750 on the internet and none seem to have the pressure balancing pipe (as I might refer to it) that my custom special has. Mine has a balance tube connecting the two inner pipes in a position just where the down pipes start to dissapear under the engine. It isn't just a structural solid pipe but allows gases to join between the two pipes. It has developed a few holes at the junction where the connecting pipe joins to the downpipe in a very awkward position to mend.

Do I need to have these middle two connected together by a through pipe or could I replace the centre two downpipes with unconnected ones?

If it's not clear what I mean please say!

Any advice very welcome.