If you wish to execute maintenance on your own Yamaha DT 50 Supermotard then it will always be a good plan to have access to a Workshop Manual for a reference if perhaps you want to know methods to strip off a particular component including Wheel Bearing and match it again in the correct manner.
Yamaha DT 50 Supermotard Workshop Manuals gives you specific diagnostic guidelines for the vehicle so if something is broken it can help you discover what the situation is and methods to repair it. After that you can evaluate if this can be done by yourself or that the job is simply too big you can actually book your DT 50 Supermotard right into a suitable repair garage.
Yamaha DT 50 Supermotard manual