Intake flange ports/lines

[timwill730]

So I realized I only have 1 rubber cap on the port on the intake flange (the port used to sync the carbs). Looking into it, it looks like there should be a line that goes from the second port to the carburetor, I'm assuming to create a vacuum?

Can someone verify this and guide me as to where this line actually connects to?

Thanks in advance,

Tim

 

[timwill730]

should have specified, the bike is a '77 xs360.

 

[Under Dog]

On my '80 that port WAS connected to the vacuum petcock. However, the vacuum petcock was shot so I replaced it with a manual petcock and ended up capping the port.

I've seen it where both ports were capped individually and I've seen some who have run a vacuum or fuel line between the two ports (capping them off by connecting them together). I'm not sure which way is better. Anybody know?

 

[xschris]

If your not using a vacuum petcock just cap them off. If you do have a vacuum petcock use the right ride barb as it will be easier to attach it to the barb on the back of the petcock.

 

[Under Dog]

xschris's comments remind me:

Make sure whatever you use to cap off the barbs stays on securely. You will definitely notice a difference in riding when your non-secure caps blow off!!!

 

[arfstrom]

There was a theory sometime ago, that perhaps the tying both vacuum ports, and even the petcock together, that you may get some intake side vacuum leveling, that might help with performance. But since most of us have problems, already, it is not worth exploring those possibilities. I do use a small zip tie to make sure I don't lose a vacuum line, once I get everything running.