Single Key Release systems! You only need an allen wrench and if the arm actually come off the bolt does not OH you said nut......
Yeah!! where was your dust cap?? shame on you for going out with your nuts exposed!!
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk