Throttle valve spec

[JTGS850GL]

I've picked up several sets of used carbs for parts and noticed an interesting difference that I would like clarification on. On the BS34SS carbs I've seen both 135 and 140 butterfly valves. It seems that the GS1000 and 1100E carbs used the 135 valves while the GS1100G's used the 140. Can someone please confirm or refute this? Trying to sort out the extra parts I've picked up and want to know if the application is correct.

[londonboards]

Yes I have 140 butterflies in my carbs on 2 GS1100Gs.

Over the years I have accumulated a number of BS Carbs and they do show different numbers on their butterflies. When I asked this question sometime ago (it might have been on a Facebook page) the answer I got was that the number refers to the chamfer on the edge of the butterflies. The butterflies are not circular. The have to provide a impermeable shut off in a circular barrel. To do this they are slightly egg shaped and 100% closed throttle is achieved at about 5 deg off from vertical. At this point where the edge of the butterfly meets the barrel needs to be 5 deg off being flat. So look at the edges of the butterflies and see the shape.

Apparently the number on the butterfly signifies the angle of this edge, so during manufacturing, they can be matched up with the corresponding throat shape of the carb body.

Sounds plausible, doesn't it?