Are you sure its garbage? Your memory for this stuff is usually better than mine, and your ability to dig out stuff from old threads is unsurpassed, but.......slowster wrote: ↑25 Jun 2022, 8:19am I wonder if raising the derailleur by 2mm-4mm might be enough to make the shifts work cleanly. Indexing works by always moving the the derailleur cage on its pivot by the same angle. Placing the pivot point of the cage a bit further away from the chain may increase the distance which the cage moves the chain when downshifting by just enough to stop the chain falling between the chainrings.
Edit - Ignore this as it is garbage. There are two pivots and the cage moves horizontally through the same distance for any given amount of cable pull..
I think I remember Brucey writing that correct chainline was important not only so the mech. could reach both ends, but also the "throw" of the mech. wasn't strictly linear with cable pull, so that you had to get the rings in the right place for the mech. to deliver the right amount of throw for each change.
I also seem to remember something about the STI pulling differing amounts of cable depending on which shift it was, but that might be for the rear.
Having re-read it all, I'm not certain we are talking about the same stuff.........