>My experience in the real world is that right hand threaded fixed
>cups loosen up occasionally if they're not installed REALLY tight.
>I've seen this happen occasionally on rides with friends (not ever
>on my bikes). The left hand threaded left pedal and the left hand
>threaded fixed cup are a simple solution to an existing problem.
I've had that happen on a bike with a modern BB that had lockrings on both sides. Well, modern is relative - it was an early Syncros BB, almost within the CR timeline.
However, if it happens on your CR timeline bike, the trick to get home is simple: Use a big gear, and pedal one revolution forward and three back. Backpedaling will screw the cup back in, and forward pedaling will unscrew it. Of course, if you have steep hills, etc., it might be necessary to walk, but it worked for me for 15 miles.
It happened twice, and then the offending BB was replaced with a Campy C-Rec (which has the same cups as within-CR-timeline Super Record), and no further problems were experienced. -- Jan Heine Editor Vintage Bicycle Press c/o Il Vecchio Bicycles 140 Lakeside Ave #C Seattle WA 98122 http://www.vintagebicyclepress.com