ebonyandivory UberDork
July 17, 2017 3:08 p.m.

The petcock delivers fuel with vacuum provided by the engine.

Since these petcocks aren't my favorite, does anyone know if I replace it with a more common petcock, will fuel still get to the carbs? I was looking at an old Norton Commando and remembering my 1974 CB 750 and just want to use a simpler petcock.

PS: the current petcock has no on/off/reserve like most, it's got a prime and run indicator.

Furious_E SuperDork
July 17, 2017 3:31 p.m.

I see no issue, just cap the port on the intake runner or wherever it's pulling the vacuum from. The vacuum petcock just keeps the fuel from flowing when the engine isn't running.

ebonyandivory UberDork
July 17, 2017 3:54 p.m.

In reply to Furious_E:

I need to look again but I believe I'll need to make a block off plate in the pattern of the original. Unless the '81 has the same pattern yet has the "normal" petcock.

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