If you have to carry out adjustments to your Xmotos XB 21D then it is usually a great idea to own a Workshop Manual for personal reference just in case you want to know how you can strip off a specific component like the Gearbox and fit it again accordingly.
Xmotos XB 21D Workshop Manuals are able to offer certain diagnostic facts for your car or truck so if something is playing up it will help you discover what the issue is and easy methods to fix it. After that you can assess if you can do this yourself or if ever the job is too big you can actually make a reservation for your XB 21D in to a trusted mechanic.
Xmotos XB 21D manual