Originally Posted by
DScott
As to torque, 50Nm is *tight*, just about as hard as you can crank on the 12" wrench while holding the cassette with chainwhip. Hard to over-do it, unless you're stupid strong, or use a vice to hold the lockring tool or something. You should feel the teeth on splined side of the lockring kind of "ratchet" as you cinch the lockring down that last turn or so.
If the cassette is tight, then the rattle noise has to be der./chain related.
IMHO, that's way too tight for the retainer. I take the removal tool and use it to hand tighten the retainer, then I take a 1" closed wrench, and tighten about 1/3 turn. That's it. I've run into guys who overtighten the retainer, lot's of luck removing it next time you want to service it.