What is this carb fitting?

[Wilson]

Recently joined this great forum after purchasing a 1985 GSX-R750.  I’m cleaning the carbs and I don’t know what this fitting does.  There is one linking carbs 1&2 and one linking carbs 3&4.

I live in Killarney, Manitoba, Canada. Slabbies are rarer than hen’s teeth in this part of the world.

[Gammaboy]

Looking at the fiche, they're for breathers.

http://www.mickhone.com.au/partFinder/fiche/suzuki/1985/gsx-r750/carburetor#ficheZone

 

[yyt]

Welcome,

Will be great to see the bride..

The fitting is the air vent.

 

[Wilson]

Thanks for your help.