One of the old tricks was to combine the top half of a Campagnolo Sport which has a sprung upper pivot with the lower half of a Gran Sport which has a sprung lower pivot. You would have to pop out the rivets to do this. Sports are rare enough now that it would be a shame to sacrifice one for a project like this, but maybes there's one with an intact upper pivot and smashed cage out there.
Leonard Bulger Ann Arbor, MI
Louis Schulman wrote:
Also, and as an article in the last Rivendell Reader points out, Simplex derailleurs, including the much maligned "Prestige", have dual sprung pivots, which would seem to be useful in such a project. That article mentions the existence of "tricks", such as attaching the cable to the "wrong" side of the anchor bolt, to achieve compatibility (presumably with indexing). Anyone tried this? What other "tricks" are there?