Petcock: Fuel flows in the "stop" position (kz400)

Had this issue on the stock kz400 petcock. Fuel would continue to flow out of the petcock in the "stop" position.

Replaced the petcock with a new cb750 petcock today. same issue.

I'm testing the petcock off the bike.

Is this normal? I know the float needle will regulate the flow of gas into the bowls, but i'd assume the petcock would stop fuel flow...

Not trying to be insulting, but are you sure you are pointing the handle in the correct position? The big end of the handle (where the red arrow points in the image below) points to the setting. So in the image below the petcock is set on "RES". Ed

im mildly insulted.

yes its in the off position.

would this have anything to do with testing it off the bike?

Sorry about the insult; I have seen folks confused as to which end points to the position marked on the petcock.

With a manual petcock (ON; OFF; RES type) it shouldn't matter if the petcock is on or off the bike. If you attach a piece of tubing to the fuel line port, when the petcock is in the OFF position if you draw a vacuum on that tubing the petcock should no let air enter the tube. Ed

I think that answers my question. Thanks for your time

650ed wrote: Sorry about the insult; I have seen folks confused as to which end points to the position marked on the petcock.

With a manual petcock (ON; OFF; RES type) it shouldn't matter if the petcock is on or off the bike. If you attach a piece of tubing to the fuel line port, when the petcock is in the OFF position if you draw a vacuum on that tubing the petcock should no let air enter the tube. Ed

I think it's a valid point Ed, easy to check the simple things first and I actually struggled with this last night myself. Pops had to teach me exactly what you just pointed out, I was 180 degrees out. So I don't think it's unreasonable to check on, just my 2 cents though.

- Irish