If you choose to accomplish auto repairs to your Gilera GP 800 then it is always a good plan to own a Workshop Manual to keep just for personal reference in the event you need to know how to strip off a certain component including Door and install it again in the correct way.
Gilera GP 800 Workshop Manuals will give you particular diagnostic facts with regards to your car therefore if something is not working it can help you understand what the issue is and methods to repair it. After that you can evaluate if this can be achieved yourself or if ever the job is just too big you could make a booking for your GP 800 into a trusted friendly mechanic.
Gilera GP 800 manual