So . . . I know that Sheldon says that the S3C is no good; unfortunately, that doesn't change the fact that I have one. Nor does it change the fact that I can't afford a new wheelset. So I'd like to figure out how to fix this one.

The issue I'm having is that when the bike is in III, the cranks need to rotate almost a full rotation (sometimes more, sometimes less) before the brakes, well, brake.

The problem doesn't seem to happen in I or II.

Any ideas as to what's wrong and how to unwrong it?

Thanks!

(Also, this is my first post, so if I screwed with the decorum or something, I apologize.)