If you need to execute maintenance on your own Hyosung GT 650 R then it will always be a good idea to have a Workshop Manual for a reference in the event you need to know how to strip off a particular component much like the Clutch and install it again accordingly.
Hyosung GT 650 R Workshop Manuals will give you specified diagnostic wisdom for your vehicle so if something is faulty it can help you figure out what the situation is and methods to fix it. You can then assess if you can do this on your own or in the event the job is just too big you could make a booking for your GT 650 R in to a local garage.
Hyosung GT 650 R manual