Is this a vacuum gauge take off port? CM400

[Windmill John]

Curiosity question at this stage, as still working on other parts of the bike. But as there’s two of these, just wondered if I’m guessing correctly.
Thanks.
.

 

[LongDistanceRider]

Yes, that's the vacuum port

 

[Windmill John]

Thanks Jim, couldn’t think of any other reason for it and seemed in the right place.

 

[Boosted]

I found this helpful :

 

[Windmill John]

Thanks. Luckily, decades ago I bought a four set of Davida vacuum gauges. Used them many times and now I have a twin again…