that is a great looking bike and we need more pics of it. but what we really need are pics of the axle. take a closeup of the axle as if you are looking at to install the Fwheel tool.
I am not sure but there might be a circlip that holds the parts that would be regular locknut on a standard axle. I think I have some Roval maint info, let me look around.
what kind of RD is that?
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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