Osgear was indexed in the 1930s, with no parallelogram at all...
here is a nice article by listmember Hilary Stone:
http://www.classiclightweights.co.uk/
also recommended reading: 'the dancing chain' by f. berto though i have not seen the new edition...
andrei padlowski
brooklyn, ny
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>>Haven't we seen examples of a couple of the very early derailer systems
having an indexed lever? I can't recall which one(s), but I have a picture
in my mind of a sort of sprung, toothed slider alongside the shift lever, a
system that would be relatively easy to craft at home.
On a related note, I recently got a '79 600 Arabesque derailer to nicely index a standard 6-speed using a 7-speed Accushift lever, much as a pre-'96 Dura-Ace derailer would function. I found this surprising in that every good index derailer is a slant parallelogram, while the early 600 is not. Conveniently, it even came with a barrel adjuster.
David Snyder