Did you ever get an answer to this?
Hi. Did you find out why your hub does not shift? I'm asking because I have one that also doesn't shift. I have put five new indexing springs so far, and have changed several internal parts. Each time the indexing spring has its little fingers squashed into oblivion. It shifts while on the stand, but never goes more that a few hundred feet before I feel the low gear become high gear, and then after that it never shifts back to low gear. Any tips for me? Not just conjecture, I want to hear from somebody who actually understands these and has successfully repaired them.