If you have to accomplish fixes to your Aprilia TXR 312 M then it is usually a good plan to have access to a Workshop Manual to keep just for personal reference in the event you need to know the best way to strip off a certain part like the Door and install it again accordingly.
Aprilia TXR 312 M Workshop Manuals provides identifiable diagnostic facts for the vehicle so if something is playing up it will help you identify what the problem is and how you can correct it. You will be able to assess if you can do this by yourself or if ever the job is just too big you can actually make a booking for your TXR 312 M right into a trusted friendly mechanic.
Aprilia TXR 312 M manual