I have Ti456 with the new swapouts. The swapout bolts to the frame, the adaptor to the swapout, and finally the caliper to the adaptor. The result is, that despite nice tight bolts, there is noticable movement at the rear brake. Applying the brake and rocking the bike back and forwards shows the caliper to moving in a kind of twisting side-to-side motion rather than the back and forwards tat would result from loose bolts.

The frame isn’t noticibly flexing, and neither id the adaptor or the caliper. My conclusion is that the swapout itself is the part that is flexing. As it is alloy, can that be a good thing?

Mine doesn’t seem to do that…what rotor? I’m using a 180

Sorry, only a 160mm – Shimano XT brakes.

I’ve spoken to our mechanics and in their collective opinion, backed up by my own experience with XT brakes, the rock / flex is inherent to the brake caliper- certainly not the swap-outs. Shimano pads rock more than Avid, and if you’re using centrelock rotors theres normally a little bit of rock there too. The swap-outs are stiff as you like…

would be easy enough to check – zip tie on seat stay as a ‘pointer’ so that the end is just touching the disk mount and then try and rock bike with brake on – see whether there’s movement relative to the zip tie. I’d guess not – as per on-one it’ll be the pads moving int he caliper or the disk/disk mount/hub having some movement in it.

aye those swap outs are bloomin thick so it won’t be them causing it. More likely every bolted joint in the set up which will be on any bike: adapter to swap out, adapter to caliper, rotor (CL possibly more so than 6 bolt depending on spider design) and then flex in the caliper (more if 2 piece) and pad interface etc etc.

There could be some flex in the swap out to frame but the other bolts mentioned are smaller so probably less than the other places.

If you have any washers as spacers anywhere they will add massively to bolt bending.

I’ve just put some superstar pads into 160mm XT rear brake and there’s a fair bit of play when you rock the bike with brakes on (and it howls in normal use) Didn’t notice it before so presume these pads don’t fit quite aswell as previous, not 100% tho (I have used SS pads before no probs but not sure if I’ve used XT ones)