Last week, riding home from work, I used a little more rear brake than usual and it felt “crunchy.” The BMW R1200GS has integral brakes, meaning that when you engage the front brake you automatically engage the rear brake as well. I tend to be light on the brakes in general, using them mostly to signal motorists behind me.
When I parked the bike I felt the rear rotor–blazing hot. The front rotors were cool. I checked the inspection hole on the rear brake pad and found that I could see just a little bit of rotor. Fortunately it’s easy enough to replace the rear brake pads on an R1200 GS. I followed this procedure here and it was a snap.
The toughest part of the whole operation was getting the ABS mudguard back in place. The tricky part was aligning the steel positioner for the top bolt:
(Photo: Jim Von Baden. See his site for excellent tutorials.)
The secret…or what worked for me…was to loosen the Torx bolt that holds the positioner to the brake caliper, then thread the long bolt for the mudguard through the positioner and into its hole in the final drive bracket. (Leave the mudguard off for now.) Next, torque down the brake caliper. Finally, remove the long bolt, put the mudguard in place and tighten the long bolt in place. The two small bolts should be easy to align.
I rode the bike to work and back today and what do you suppose. The rear brake rotor is still getting really hot! After some research it seems that a hot rear rotor is “normal” for a BMW GS. Go figure.