I own a 2011 R12GS that I purchased new from the dealership. The motorcycle is fantastic!
After about 2000 miles I started to feel the front brake surging. At 6000 miles the surge was very noticeable mostly at slow speed, light braking, while coming to a stop. Took the bike to the shop under warranty and they found the left front brake disc to not have the same thickness around the disc. The run out was just within spec but it was written up knowing the condition was progressively getting worse. BMW replaced the disc under warranty. Only the disc affected was replaced.
Now at 11000 miles (one year later) the same problem has come up again. Called the dealership to make an appointment. The service manager asked why both discs were not replaced the last time I was in since they are usually done in pairs? I said I had the same question? So, back to the shop I went and they found the same problem with the left disc. They feel the problem is the cast aluminum wheel not being square where the disc is bolted on. A left disc and new wheel is on order to fix the problem under warranty.
My question is this, should both discs be replaced? It does not make sense to me to have one disc with zero mileage and one with 11000 miles on it? I asked that both be replaced under warranty and they are asking BMW for approval? Also, should the brake shoes be replaced with only 11000 miles on them? The wear on both sets are wearing evenly.
For those of you more mechanically inclined, your opinion would be appreciated?