The pin stops the nut turning In your photo the nut has tightened with the flat of nut opposite the pin that can often happen but if the nut wanted to turn the point of the nut would touch the pin preventing further turning The Brampton’s on my rapide never had that pin I have thought of fitting one but the axle tightens up ok so never haveMy F55 balance beam, shown above, appears to be a "bent" Girdraulic version , rather than a Brampton style.
I am remembering the correct balance beam would not clear the Brampton tubes.
So, what does the Brampton axle nut pin E128 do?
It would appear to be expecting a larger AF nut. OR?
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