Harvey Sachs states:
The Sport required a small spring-stop hole in the rear drop-out, centered above the derailleur mounting bolt.
and Chuck Schmidt replies: The Cambio Sport came assembled to a bolt-on derailleur hanger (claw) and for this reason didn't require a drop-out with a spring-stop hole. The claw could be omitted from the Cambio Sport when mounted to a Campagnolo drop-out with the requisite derailleur hanger and spring-stop hole.
Picture of Cambio Sport derailleur:
http://homepage3.nifty.com/
Chuck Schmidt South Pasadena, Southern California http://www.velo-retro.com (timelines, reprints & t-shirts)
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