Stock Carbs - Is Float Height Setting Tied to Carb or Bike?

The Standard

XS650 Addict
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Los Angeles
I have set of BS34's installed on an XS2. The Clymer manual states two different Float height specs - one for 1970-1979 (24mm height) bikes and the other for 1980 and later (27.3mm height). Assumption is the '70-'79 bikes had the BS38 carbs only.

My question is do I set the floats on the BS34's for 27.3mm which is that carbs spec or the 24mm spec for '70-'79 bikes ~ engines.

Seeking to confirm if the float adjustment follows the carb or motor they are installed on?

Additional detail: Motor they are being tuned for has open exhaust and super low restriction induction setup and jetting change.
Mainly Carb
Angle of such is some change from that.

Bear in mind, fuel sloshing and foaming is paramount. Need that MJ low.
Thanks. I did set the floats to the carb’s spec over weekend and was hoping correct approach.

Surprised how much I had to bend the tang from horizontal to get the 27.3mm height. Looks like a “sliding board” almost. The digital caliper does confirm that distance though.

Assuming the floats were not swapped out. They are black plastic with chromed steel bracket/tang.
Then you used the wrong spec, lol. That's why you had to bend the tang so much. The plastic float spec is 22mm ± 1mm. That 27.3mm spec is for the brass floats used in the 1980 model only. Unfortunately, the manuals didn't catch up with the carb change until several years later. Many still show that 27.3mm spec.

This pic from a Suzuki manual shows where to measure from, the round part of the float "bulb", not the flat part up by the pivot .....

Wow! Thanks @5twins. That does explain it. I did take measurements at the highest point of the curved section of float, with gasket removed.

I'll reset them now with that confidence you provided here.

Did Clymers update their 650 manual? If so it would be good for me to get the latest one. Can only imagine what other specs on projects I followed that have had a consensus on better or different numbers or service technique.