Brake Grind

[lzh1982]

Hi

I have a Giant Talon 2 I bought in 21 and last year I replace the rear pads with geniune Shimano pads. Ever since the replacement, I been getting this brake grinding when I apply the rear brakes. Harder on the brake levers, harder and louder the grinding noise as the bike comes to a stop.

I checked few things like caliper alignment (no rubbing when free spinning) and disc warp and they all seem okay. I even tried sand off a bit brake pad material and try to bed in again, but still the same. Front ones are fine as it still has the 1set of pad from new. Closer visual shows the rear rotor a visibly more streaked than the front and more shiny too. Could it be that I didn't bed-in the pad propertly? Or I could have got some bad pads that destroy the rotor?

Before I go replace the rotor and pads, I thought I post it here to see if there is any easier remedies.

Thanks.

[Retrobyte]

Next step may be to buy some brake cleaner and clean the rotor - spray it generously onto a clean cloth, and wipe over the rotor surface, then wipe off with a clean and dry cloth. Then go through the brake bedding routine again. If that still doesn't fix the noise, my guess is that the pads have been contaminated somehow, so try another new set of pads - making sure you don't touch the surface or get anything else on them before you bed them in

[robbo mcs]

Is it a grinding noise, rather than a squeal?

I have had similar when replacing organic pads with metallic. I think the metallic pads didn't react well to the organic pad material already on the disc surface. Settled down eventually, although still noisier than the organic.

I normally prefer organic, but ended up with the metallic ones during covid, when there was a shortage of pads