If you have to undertake fixes to your Gilera RC 600 then it is always recommended to own a Workshop Manual to keep just for personal reference if perhaps you want to know tips on how to strip off a specific component including Brake Discs and fit it again successfully.
Gilera RC 600 Workshop Manuals can offer you detailed diagnostic information for the automobile so if something is not working it can help you ascertain what the situation is and how you can correct it. After that you can evaluate if you can do this yourself or that the job is simply too big you could make a reservation for your RC 600 in with a nearby car garage.
Gilera RC 600 manual