I imagined they worked by allowing the frame to be stretched apart just enough to allow the belt to be inserted. I can't recall seeing couplers on an aluminium or carbon frame.
Oh yes, I was thinking of the coupler unscrewing and making a gap. I may have made those couplers up though :-)
Oh yes, I was thinking of the coupler unscrewing and making a gap. I may have made those couplers up though :-)