…Shimano M525 cup and cone hub locknut. The non-driveside locknut is always coming loose. I’ve replaced the axle and locknut but still I keep getting play in the wheel and it is always because of the locknut loosening.

are you using a cone spanner to hold the cone while you tighten the locknut??… tighten it tighter!!

Yes. Tighter than b****ard tight?! Without getting the big 12 inch adjustable spanner out I’m not sure how much tighter it’ll go 😯

Loctite 278 iirc.

It’d suggest there might be something else wrong with the hub or frame.

that is not a place i’d be wanting to use loctite. Sounds like you are possibly not tightning the cone into position enough allowing everything else to come loose or possibly not tightening the lock nut enough, as hendo says cone spanners are a must to do the job properly.

It’s not the only frame it’s done it on. How can it be something wrong with the hub? After all it’s just a locknut tightening against something. What complicated mechanics am I missing?

cone spanners are a must to do the job properly.

I have – and use – cone spanners. I suppose the next question is “what torque for hub locknuts?”, since I believe I’m tightening them enough but evidence suggests otherwise

Well if the cone is good and the bearings are good and the axle is new then the only remaining part that could be damaged is the bearing race in the hub shell, at the end of the day it amounts to the same thing – bearings having extra space to move lateraly allowing the cone to move away from the locknut and the hub becomes loose.

Mmm, now whilst that does sound expensive/terminal, I’ve been looking at excuses for new wheels for quite some time…

Cheers

🙂

Sorry it was 270 for the locking stuff.

222 for everything.