Found a pic of Mark Stonich's mod to the cage:My mod, with the Suntour piece grafted in, brings the inner cage up higher than his, possibly making mine even better at preventing the
"DuoPar Blues". But it's possible to make it too high. You don't want the inner cage rubbing on the largest sprocket when the chain is on the 2nd-to-largest. Mine didn't rub, but I don't remember what the sizes were, or more importantly the jump in sizes from 2nd to 1st. I think the jump in sizes is what limits how high the cage can come. That mech isn't on any bike currently, so I can't really test that. (I sold the bike it was on, but the buyer wanted Campy, so I still have the one I modded.)

One nice thing about the Stonich method is you could start with it taller than the one in the pic, and then saw or grind some off, if it turns out to be too high.

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