If you want to execute auto repairs for your Aprilia ETX 350 then it is usually a great idea to have access to a Workshop Manual to use as reference in case you need to know ways to take out a specific component much like the Gearbox and install it again perfectly.
Aprilia ETX 350 Workshop Manuals offers you exact diagnostic info for your vehicle therefore if something is not working it helps you figure out what the situation is and tips on how to correct it. You can then assess if this can be achieved by yourself or if the job is just too big it is possible to book your ETX 350 into a suitable car garage.
Aprilia ETX 350 manual