If you want to carry out maintenance on your own UM GP1R 150 then it is always recommended to own a Workshop Manual for a guide just in case you want to know the best way to strip off a certain component for example the Drive Shaft and match it again in the correct way.
UM GP1R 150 Workshop Manuals can offer you specified diagnostic guidelines for your vehicle so if something is not working it can help you understand what the situation is and ways to make it better. You can then determine if you can do this on your own or in case the job is just too big you can still book your GP1R 150 right into a local friendly mechanic.
UM GP1R 150 manual