If you wish to accomplish repairs on your BMW R 850 R then it will always be recommended to have a Workshop Manual to keep just for a reference just in case you need to know simple methods to remove a particular component for example Drive Shaft and match it again in the correct way.
BMW R 850 R Workshop Manuals gives you specified diagnostic info on your automobile therefore if something is broken it can help you ascertain what the situation is and ways to repair it. After that you can evaluate if you can do this on your own or in case the job is just too big you can still make a reservation for your R 850 R in to a local car garage.
BMW R 850 R manual