2017 BMW R 1200 Gs Adventure

It is not clear which rear brake component is failing. It seems to be either the master cylinder or the ABS control module, but nothing seems to be conclusive. The failure alters the power of, and force required to apply, the rear brakes, changing the riding characteristics of the motorcycle that could lead to serious injury or miscalculations in application of the rear brake to minimize stopping distance. Apparently the component has been inspected by the manufacturer, however there has been no concrete solution that would guarantee a permanent fix. There are no warning lamps or visual indicators to prepare riders that the rear brakes may be compromised or dysfunctional. There have been multiple incidents of this failure from new. After 7 years and over 800 posts (in this thread alone), owners and BMW dealers have not been able correct the defects with 100% certainty. [XXX] This impacts owners of this motorcycle with a Production Date Range of Sept 1, 2012 through to Aug 31, 2020. BMW knows of the problem and released a Technical Service Bulletin SIB 34 01 21 to Dealers [XXX] . INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I bought a 2017 BMW R 1200 GS used from a dealer with 554 miles on it. Basically new. I put 1100 miles on the bike before I had a work related accident. The Bike has 1687 miles on it now. Bike has been sitting for 3+ years in a garage. The rear brake goes all the way to the bump stop with no resistance. With the bike on the center stand and the rear brake lever all the way down to the bump stop, the rear wheel spins freely. I rode this bike 2 days before my accident in July of 2020 and the rear brake worked fine. I have not rode the bike in 3+ years and the rear brake went flat. This is unacceptable. I think BMW knows there is a problem. I want you to know there is a problem so maybe the problem get fixed. I've read post on BMW forums, explaining the rear master cylinder sucks in air. Air in brake lines is no good. That means the rear brake master cylinder could suck in air and render the rear brake useless. I think Brakes are an especially important part of vehicle safety.

I HAD LESS THAN 6000 MILES ON MY BMW R1200GS ADVENTURE AND NOTICED THAT I HAD NO REAR BAKE AT ALL WHEN I WAS RIDING OFF ROAD WITH MY "ENDURO PRO" MODE ENGAGED. THIS ALLOWS ME TO USE THE REAR BRAKE IN AN OFF ROAD MODE AND SHUTS DOWN ABS AND TRACTION CONTROL.. I NOTICED THAT A LOT OF OTHER PEOPLE ARE HAVING THE SAME ISSUE WITH THIS MOTORCYCLE. SEE ADVRIDER.COM AND SEARCH REAR BRAKE FAILURE ON BMW R1200GS. I TOOK IT TO THE DEALER AND THEY BLED THE BRAKES. THEY NOW WORK FINE. IT HAD BEEN SUGGESTED BY OTHERS THAT THE BREMBO REAR MASTER CYLINDER IS TO BLAME. IT ALLEGEDLY ALLOWS AIR INTO THE SYSTEM.SOME DEALERS HAVE REPLACED THIS AND IT HAS SOLVED THE PROBLEM. THE BRAKE SHOES WERE IN GOOD SHAPE AND WERE NOT REPLACED. I AM ASKING THAT YOU LOOK INTO THIS AS FAILURE OF THE REAR BRAKE COULD CAUSE SERIOUS INJURY ESPECIALLY OFF ROAD AND GOING DOWNHILL. THIS IS WHERE THE REAR BRAKE IS VERY IMPORTANT. VERY RESPECTFULLY,