If you wish to accomplish maintenance to your Yamaha YBR 125 then it is usually a great idea to have access to a Workshop Manual to use as a guide just in case you need to know tips to take out a particular component including Wheel Bearing and match it again correctly.
Yamaha YBR 125 Workshop Manuals gives you specified diagnostic info for your car therefore if something is playing up it helps you ascertain what the problem is and how you can fix it. Then you are able to assess if this can be done on your own or if the job is simply too big it is possible to book your YBR 125 in with a decent car garage.
Yamaha YBR 125 manual