‘81 carb passage question

[MtnMann]

Greetings,
I have an ‘81 that I’m cleaning/rebuilding carbs on.
I don’t have a manual yet but I’ve been able to clear out all passages in the carbs I can find. My question is about this passage from the left hole under the slide guide which I can see has a passage way to the right tower in the group of towers in the center of the carb bowl. This passage appears to be blocked off (and not by crud). Can someone confirm this passage is not used on the ‘81 carbs? I see pics of older carbs with either jets or rubber plugs on this tower.
Thanks!

[MtnMann]

5DA0616A-19CC-46C9-A961-4D23666A2314.jpeg

4E5B3083-D554-47FD-BACE-AAE8BCFA744F.jpeg

[MtnMann]

Thumbnails of pics rotated 90 degrees to the left.
So holes I’m talking about are bottom hole in first pic, too hole in second…

[bobcat]

comment withdrawn. It seems you are describing 2 different circuits.

[MtnMann]

Thank you!

[bobcat]

In your first pic the hole you describe would be for the primary main air jet in te older carbs.
The second pic you describe as having the rubber plug in older carbs is the pilot (slow) jet.
The tower not used is for the primary main jet.

[daves79x]

Did you extract the pressed in idle jets? I can't tell from your picture. Did you buy a complete Viton rubber rebuild kit? There is a lot more than meets the eye here if you are flying blind and have never done a set of CBX carbs before.

Dave