If you want to conduct maintenance on your own Suzuki GZ250 then it is usually recommended to have access to a Workshop Manual to keep just for personal reference just in case you need to know the best way to strip off a particular part for example, the Brake Pads and match it again the right way.
Suzuki GZ250 Workshop Manuals will give you identifiable diagnostic facts for the automobile therefore if something is broken it will help you work out what the situation is and tips on how to correct it. You can then decide if this can be achieved on your own or in case the job is simply too big you are able to make a reservation for your GZ250 in with a suitable car garage.
Suzuki GZ250 manual