If you have to do auto repairs to your Moto Guzzi 650 GT then it is usually a great idea to possess a Workshop Manual to keep just for a reference if you need to know how to strip off a particular component including Gearbox and match it again accordingly.
Moto Guzzi 650 GT Workshop Manuals will give you exact diagnostic details on your automobile so if something is playing up it can help you find out what the issue is and tips to correct it. You can then analyse if this can be achieved yourself or in case the job is too big you can actually book your 650 GT into a nearby mechanic.
Moto Guzzi 650 GT manual