Originally Posted by
Troul
I had a set that worked fine for a few dozen miles, then squealed when cold or wet. Returned them & roughed up the replacements with 100 grit then 150 grit followed by brake parts cleaning them.
Same pads as before, replacement discs & no noise. Have over 1000 miles on them.
The first set as well as the replacements had a very smooth almost polished surface. That to me, exacerbates glazing or a very low resistance to achieve necessary friction needed. YMMV
Everyone knows that regular rim brake pads need to be towed in to prevent squeal. The same goes with disc brakes. The caliper needs to be very carefully made parallel with the disc, or ever so slightly towed in just like rim brakes. We are talking only 1 to 5 thousands of an inch here. You need shim material under the caliper mount.