If you choose to do adjustments on your Yamaha XJR 400 R then it is always a good idea to have a Workshop Manual to use as reference in the event that you need to know proven methods to take off a specific component much like the Brake Pads and match it again efficiently.
Yamaha XJR 400 R Workshop Manuals can provide specific diagnostic wisdom for your car therefore if something is faulty it helps you ascertain what the problem is and methods to correct it. You can then determine if this can be done yourself or in the event the job is just too big you are able to make a reservation for your XJR 400 R in to a trusted garage.
Yamaha XJR 400 R manual