So I had some scraping on my rear brake under heavy braking on my 2006 BMW F650GS and the brake fluid reservoir looked low (not always a sign of worn brakes, but in this case it was). Ordered the new brakes through amazon, there are a few brand/styles out there, but I felt this one fit my need the best (EBC Brakes FA213 Disc Brake).
The tools I used were pretty minimal:
-Hammer
-1/4" Socket Wrench with T-30 Torx
-Center Punch/Screw Driver/Your metal piece of choice
-Nail (or similar)
First off I removed the rear plastic chain and tire guard with the T-30 torx and set it aside. I dont think you have to remove the plastics, but it makes it a lot easier.
Secondly I used the needle nose to pull out the cotter pin from the brake.
Once the cotter pin is out you have to pound out the metel pin from the left hand side of the bike. I found the a nail worked pretty well and went out pretty easily. Although it is stuck in there avoid using products like PB Blaster/WD40 near the brake components.
Once the pin is out, push in on the caliper to compress the piston (you will see it move in easily). Then the pads just come out backwards and new pads slide back in. To get the pin back in you really have to pound it from the other side of the tire. A recommendation I saw was to press the brake lever to tighten up the new pads making it easier to pound in the pin. I used a flat head screwdriver that was already damages (probably from using it inappropriately as a pry bar at some point). It is in far enough once you can see the hole the cotter pin goes it on the inside by the pads. Keep in mind the cotter pin rests in a 45 degree forward cant so make sure you line it up going in the same way it came out.
Below you can see the new pads installed:
New pads compared to the old pads:
