Topic: CB750 Crankcase Ventilation

[banzaibob]

Right now I have the crankcase vent on top of the valve cover vented to a spigot on top of my airbox.  What would be the advantages of putting a pvc valve inline?  What about putting a pvc valve inline and simply running it to atmosphere?  Does anyone have a diagram as to where the stock vent line are suppose to go, oil tank, etc.? 

[MCRider]

Older models vented to atmosphere via tube from vent to swingarm. Newer models vent to airbox so fumes are ingested by engine and burned.

I see no reason to do anything different.

[Bailgang]

I don't see how putting a pcv valve in the existing vent hose as it is routed whether it be to atmosphere or to the air box will have any effect. The carbs and intakes on our bikes aren't designed for the use of a pcv valve in the first place. My guess is that if you were to use a pcv valve and route it as it typically is for example on a car engine meaning going from the valve cover directly to base of the carb into the intake manifold then your cb750 carbs would then behave as if they had an enormous vacuum leak.