The cable guide (sorry, I don't know the technical term) where the rear derailleur cable attaches to the downtube on my Co-Motion tandem has mysteriously broken in half and no longer holds the cable in place. Since it is no longer held in place, the derailleur is currently inoperable. The frame is aluminum. Is there a (relatively) easy fix for this? Perhaps a camp on accessory that would serve the same purpose rather than having to repair the frame? Any guidance you can provide to help get the bike back into usable condition would be appreciated.[/ATTACH]