If you wish to execute fixes for your Yamaha YBR 250 then it is usually a great idea to possess a Workshop Manual to use as personal reference if you want to know how you can take off a specific component for example, the Drive Shaft and match it again in the correct manner.
Yamaha YBR 250 Workshop Manuals gives you distinct diagnostic info on your car so if something is broken it can help you ascertain what the situation is and how you can make it better. You can then determine if this can be done by yourself or that the job is just too big it is possible to make a booking for your YBR 250 into a local friendly mechanic.
Yamaha YBR 250 manual