Shimano XT 10 speed rear derailleurs have come in at least three different bracket axle units. The units and mounting bolts are not cross compatible. Here's a summary of the situation:
Shimano XTR brake pad weights
Shimano XT 165mm crankset
Quick facts:
Shimano SM51 Bottom Bracket
For use with Hollowtech MTB cranks. Total weight including 3 spacers 99g.
Shimano XT M775 disc brakes
The good
Shimano SP41 shift outer
This is my go-to shift cable housing. The SP41/XTR housing weighs 38g a metre, can be bought in bulk ( 10m and larger rolls ), comes pre-lubed with the Shimano special silicon grease and ...