You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
This is the second time I've noticed this happen. The lock ring on my rear Centerlock rotor (160mm) seems to work loose over time. I don't think it's a safety issue as the rotor's still firmly in place & I tend only to notice it if I'm stationary & rocking the bike with the brakes on (at a junction or so forth).
I've retightened the lock ring to torque and we'll see if it stays tight. If not is it as simple as thread locking it or perhaps trying another lock ring or might there be an issue with the thread on the hub (DT Swiss 370 3 pawl)?
I use some thread locker on mine:
https://www.parktool.com/en-int/product/medium-strength-threadlocker-tlr-1
With some of this:
https://www.parktool.com/en-int/product/adhesive-primer-ap-1
For good measure.
I assume your lockring has an external spline? Retention is supposed to be achieved (or at least helped) by the serrations on the lockring interfacing with the serrations on the disk, if you don't feel positive clunks as you torque them up then something is up either with the serrations or the thread bottoming out. You can also double check the thread isn't bottoming out by making sure you can't slip a feeler gauge/slice of soda can between the lockring and the disk. IIRC the threads on the DT centerlock hubs are not long, but I have not myself experienced the threads of a lockring bottoming out.
In my experience Centrelock lockings dont tend to work lose (especially if torqued correctly) but once they do it once they tend to do it again.
Considering the basic shimano lock rings are only £4 a pop I'd just replace it for the sake of peace of mind.
Thanks.
It's the same lock rings & hubs at the front, but no trouble there.
I have an old cassette lock ring, could I try this or do I need something Centrerlock specific?
You will need a dedicated Centrelock lock ring I'm afraid.