When I drag the rear brake to scrub off some speed I get the most horrendous loud ball aching vibrations through my frame. (Ti456)
Tried upping rotor size from 160 to floating 180- cured for a bit. Thinking of refitting a totally round shimano 160 and dob of assembly grease on the back of the pads. Any suggestions?
Don't drag the rear brake.
Mrs ssstu had this problem with an Avid rear brake.
Tried diffent pads, different rotor and faced the frame. None of it made it any better.
Bolted an old Shimano LX brake on and the problem never came back.
is everything aligned? have you checked your rotors for being warped? surely you shouldn't get vibrations: just squeeling!
Rotor runs free - it's full on vibrations of the simple harmonic motion kind. Something is moving and sending the whole frame in harmonic sympathy. No idea what though.
I've had the same problem with my rear Shimano brake for a couple of months. The problem is intermittent but when it happens the vibrations go right through me. So much so that I have to release the brake slighty for the vibrations to stop. However as soon as I release, I can brake again with no problem.
I've cleaned the caliper, fitted new pads, bleed the brakes, aligned the caliper but this has made no difference. I've looked at the rear disc and it doesn't appear to be warped but I'm now going to swap the discs around, to see it the problem transfers to the front (and is therefore disc related).
If this doesn't solve it, I guess I may need to buy new brakes!
I have a simmilar issue on a Ti-inbred running Shimano LX; no solution yet but you are not alone!!
Now solved with old Hope minis and 140 rear rotor. Plenty of stopping power for wee me.
In my limited experiece:
A- A warped rotor (but you've tried another one)
B- One piston is moving/pushing/working more than the other. As the rotor passes the pads - the bit nearest the rotor spider arms flex less than the bit between the arms. This gets translated into a low frequency vibration - I guess the frame / wheel is forced to flex to compensate and you feel this in your seat.
Try breaking later and harder just to see if it makes a difference.
Was having a similar problem with my old Mono Minis, and noticed that the braking surface tapered off between the rotor spokes, effectively creating a step for the inner edge of the pad to negotiate.A swap to a 180mm 6 bolt XT on the front solved the problem, but the 160mm XT rear had a shallower braking surface,and still suffered judder, an old Deore rotor (no longer listed as available)worked fine until the perfectionist in me ordered a custom item from Hope.De-glazing the pads and rotor with some 180 grit wet-or-dry may help too.