If you wish to execute maintenance tasks to your BMW R 1100 GS then it is always a great idea to have a Workshop Manual to use as a reference if you want to know methods to remove a particular part for instance the Brake Pads and match it again adequately.
BMW R 1100 GS Workshop Manuals can offer you precise diagnostic information for the vehicle so if something is faulty it can help you figure out what the problem is and how you can make it better. Then you are able to determine if this can be done on your own or in case the job is simply too big you can actually make a booking for your R 1100 GS right into a suitable car garage.
BMW R 1100 GS manual