Trying to track down the source of my howling rear brake I changed everything last night, pads, brake, disc, wheel. Turns out it’s the wheel. With the brake full on you can rock the wheel back and forth. NOw I serviced these wheels not too long ago, shimano wh775s cup and cone jobs. I put in new bearings too, now I aint the best mechanic but I’ve been fannying around with C+C for years and I reckon they are tightened properly. Give the axel and wobble they feel fine, put the wheel in the frame and try to wobble side to side no play. The only play is the wheel rotating back and forth with the brake on. Centrelock discs, disc felt ok but I changed it to a spare just to be sure, same problem. Bunged on a hope rear wheel, no problem at all. Spokes on shimano wheel seem fine, wheel is true.
Any ideas?

Pads moving in caliper?

pads will always move in the calliper – sliding clearance is needed.

Splined disc fittings also give the potential for movement.

Pads moving in caliper?

my initial thought but nope, as proved by a different wheel not having the same play with the same brake and pads.

Splined disc fittings also give the potential for movement.

spline seems fine, disc feels solid enough, done up well b****rd tight.

Only other advice is that having found mine rocked back and forth after a few months hard riding, I put a bit of threadlock on the splines of centerlock rotors and then do it up bastid tight and it hasn’t happened since.

Is it a full suspension frame? My yeti groans a little bit sometimes (on long sweepy/braking turns, or might be my imagination) where the same wheel and brake on my old NRS didn’t ever howl. I surmise that it is some sort of flex between sides of the rear dropout that temporarily misaligns the rotor in the caliper under sufficient sideways force. But that is a guess, it’s never bothered me enough to ask other yeti owners about it.

full sus yeah, did turn bike over and just hold swingarm and wobble wheel in an effort to remove any flex in the frame/bearings, same result, rotation seems to be between rotor and rim, so hub, centrelock, spokes. might try lbs

I’ve noticed movement in the spider of the centerlock rotor on a mates bike. Where the metal joins the plastic.

Perhaps that?

seems solid enough and I tried another not very used CL disc, same.