Sorry if this is a hijack.... BUT...

I'm thinking about making my 29er a 1x9. Right now it's 3x9. It has a rear XTR derailleur with a long cage right now, if I were to put a single-speed crankest on the front with the long cage in the back, would that just be asking for trouble?

If so, can you buy shorter cages and just swap them out?

Edit: Currently running 11-32 on the back, thinking about going 11-34 for 1x9.