If you choose to conduct adjustments on your own Sym R1 Z 125 then it will always be a good idea to have a Workshop Manual for personal reference in case that you want to know the way to take out a certain part including Drive Shaft and fit it again appropriately.
Sym R1 Z 125 Workshop Manuals are able to offer special diagnostic details for the vehicle so if something is not working it helps you determine what the issue is and how to correct it. After that you can assess if this can be done by yourself or in case the job is just too big you can still make a booking for your R1 Z 125 into a trusted repair garage.
Sym R1 Z 125 manual