Originally Posted by
surreal
Which XTR rear derailer? An older 9speed version would work nicely, but the 10speeds are s'posedly not compatible with 9 speed shifters/cassettes, due to slightly different pull ratios.
It isn't "slightly", the 10s mtn "Dyna-Sys" cable travel is about *twice* the travel of the 9s RD's for the same amount of RD movement.
I had one here for experimental purposes.