If you want to perform auto repairs for your Ducati S4 then it is always a good plan to have a Workshop Manual for reference in the event you want to know how to remove a specific component including Brake Discs and install it again in the correct manner.
Ducati S4 Workshop Manuals will give you special diagnostic wisdom with regards to your automobile so if something is broken it will help you understand what the situation is and tips on how to make it better. You can then evaluate if you can do this by yourself or if ever the job is just too big you can actually book your S4 into a local repair garage.
Ducati S4 manual