Mystery tube

I took the tank of my bike to clean it out. While I had the tank off I noticed a tube that was capped with a screw. It is attached to the middle of carbs actually third from the left. Could this be a vacuum line intended for the petcock? The PO replaced the petcock with a universal one.Ill try to get a picture if needed. My bike is a 1978 kz1000.

Thanks
Chris

You got it dude. That's proally what transpired.


Bill

here is a picture

Thanks Bill, will this affect anything? Example would it cause the fuel to take longer to get flowing properly?

what kind of petcock is installed on there now?

Made by PINGEL or atleast that is stamped on it, Picture below

It's been a minute since I've had stock carbs but isn't that the other fuel line for carbs 3/4?

I guess anything is possible, Who knows what has been changed over the years, however I have two fuel lines running from the petcock already, one to carbs 1-2 and another to 3-4.

Thanks,
Chris

Yep, that line from the #3 carb would have supplied vacuum to the original petcock. Just leave it plugged. You need a cap on that vacuum nipple, or you'll never get the bike to run right.