I get the feeling they are to link breathers on FourK bikes with PD carbs?
The 77 F has the earlier style carbs, but that was my wild ass guess at what he was alluding to. I think it's 3.5mm I.D. tubing.
But, then, those garden gnomes are sooo wiley.
I'm just glad they aren't after my underpants.
Got enough chafing...
Cheers,