If you have to perform repairs for your Yamaha DT50X then it is usually a good plan to have access to a Workshop Manual to keep just for a guide if you want to know the right way to remove a certain part for instance the Drive Shaft and fit it again accordingly.
Yamaha DT50X Workshop Manuals will give specified diagnostic wisdom for the automobile therefore if something is broken it can help you ascertain what the situation is and tips on how to fix it. Then you are able to assess if you can do this yourself or in the event the job is too big you can book your DT50X in with a trusted friendly mechanic.
Yamaha DT50X manual