yeah, I knew that geo determined the actuation which led to indexing, but I didn't catch from your earlier post that it had anything to do with maximum cog size (or that hanger length was involved - but that makes sense).
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Bikes: 1996 Eddy Merckx Titanium EX, 1989/90 Colnago Super(issimo?) Piu(?), 1990 Concorde Aquila(hit by car while riding), others in build queue "when I get the time"