Just in the process of changing my drive sprocket to a supermax , and upgrading to the later rear hub at the same time.
I want to change the brake bleed nipples to Goodridge 'speed' bleed type.
Does anyone know the thread size - already guessed at M8 - ordered 3 but got it wrong!

I think it must be M6 or M7 - but I am sure somebody knows.
Your help is appreciated
Andrew