Cables rubbing on Brompton frame.
I just noticed yesterday a black mark on the lower frame adjacent to the crank assembly created by the cables rubbing on the frame. I thought it might be a grease mark so I tried to wipe it off. That didn't work, so I tried some carnauba wax, but it only removed a portion of the mark. I'm hoping that over time the cables don't wear through to the wire. Should there not be a barrier or shield installed in this area? Has anyone else noticed this on their Brompton?
Edit: I forgot to mention. The three cables were twisted around each other, so I straightened them out in a proper row of three. I hope this helps. Who assembled my bike errr!