Originally Posted by
Stickney
You might want to go back after installation of the cassette and you put on a few miles and re-tighten the lock-ring.
Kinda like re-torquing lug nuts after you change a tire.
Nah.
FWIW - I have a torque wrench setup for lockrings. Have done probably thousands and all at 40nm. They never loosen up. The galling is because of the poor small spline design of Shimano (that's why they tried to make the 10spd only spline a few years back - as a replacement) and the material.
See here for more details:
http://sheldonbrown.com/k7.html