VeloNews.com - Technical Q&A with Lennard Zinn: Why did Schleck’s chain come off?
It’s pretty much just speculation, but it’s fascinating speculation. And makes me glad once again that I am not a race mechanic.
Why did Andy Schleck’s chain come off today [yesterday]? It looked like he was just pedaling and not shifting.
I’ll venture my theory as to why it came off, but that’s all it is: a theory. But, I think I can definitively explain what’s unique about his derailleur that caused his rear wheel to jump up and made it impossible for him to pedal the chain back on and forced him to stop.
First, it may seem amazing that his mechanics had installed an inner stop, which, if adjusted properly, one would have thought would have prevented the chain from dropping in the first place. But I think the chain came off from the bottom and not the top, and the inner stop could not prevent that.