Originally Posted by
San Rensho
In addition to taking it back to whoever you paid to do the job right, and checking the toe, take the tire off the wheel, aggressively sand the section of the rim that the brake shoes contact with 320 grit, clean with brakecleaner. Then sand the pads with 60 grit or a file.
Is the OP supposed to do all this before or after he returns the bike to have the brakes done right?
It does however beg the question, is making sure the brakes don't squeal part of a brake job? Supposing the LBS did everything right, are they still to be blamed because the brakes squeal?
Anyway, assuming the OP would rather try and fix the problem himself, I first say check for toe in. If that looks right, I just today had to deal with brake squeal from some V Brakes; suddenly started about 100mi on some new Kool Stop pads. Cleaning the rim brake surface didn't work, but the it did look uneven and glazed. Took some 220 grit sandpaper to it (sorry no 320, but it seems it got the job done in 1/3 less time) until the surface looked clean and even. I did a test ride and the squealing is gone. BTW, I have numerous bikes with cantilevers, V brakes, calipers (single and double pivot) and disc brakes (hydro and mechanical). Occasionally one will start to squeal for one reason or another. If I ever had a bike where I couldn't quiet the squeal, I would get rid of it and that is something I rarely ever do..