Topic: CB750 Carburetor Beather Tube Size

[TrevorEllis]

Please would someone tell me the ID and OD for the CB750 Carburettor Breather Tube.  Thanks

[Bodi]

Not sure what you mean by breather tube, but I believe the four overflow tubes and the vent tube are all 5.5mm like the fuel feed tubes. I may be wrong and the vent tube in particular may be smaller?

[ekpent]

Yes they are smaller then the fuel line,more like 3-3.5mm I think I read recently. The same size is also used on the two vent nipples between the carbs. So you need six pieces of varying lengths if we are talking 1976or older roundtop carbs.

[TwoTired]

Yes they are smaller then the fuel line,more like 3-3.5mm I think I read recently. The same size is also used on the two vent nipples between the carbs. So you need six pieces of varying lengths if we are talking 1976or older roundtop carbs.

Yes, 3.5mm I.D.  Don't know why the O.D. would matter.

Cheers,