If you need to undertake maintenance tasks for your BMW C1 125 then it is usually a good idea to have access to a Workshop Manual to use as reference if you want to know how to take out a particular component much like the Brake Discs and fit it again appropriately.
BMW C1 125 Workshop Manuals provides certain diagnostic information on your car or truck so if something is playing up it will help you identify what the situation is and the best way to correct it. You will be able to decide if you can do this on your own or that the job is simply too big it is possible to make a booking for your C1 125 in to a local mechanic.
BMW C1 125 manual