[QUOTE=Panthers007;8301870]The Duopar was the first DUAL-parallelogram derailleur commercially marketed. At least that was the hype back then. And we all had to have a few. Why a few? See my previous post.[/QUOTE


I don't think there were any other dual parallelograms. If there was one, I'd think it was an even more obscure Huret.

I find it shifts a lot better than a slanted Rallye, because it shifts right away and doesn't overshift. If I pedal backwards and the cage is not well-aligned with the cog the chain is on, I can get chain jamming, and need to stop and clear it or sometimes a well placed shove with my foot will help. But no breakage.