If you have to execute auto repairs on your Gilera GSM 50 then it is usually a good idea to have access to a Workshop Manual for reference if perhaps you need to know ways to take out a particular part for example, the Wheel Bearing and match it again successfully.
Gilera GSM 50 Workshop Manuals will give you specific diagnostic guidelines with regards to your car so if something is playing up it will help you find out what the problem is and the best way to correct it. You will be able to evaluate if this can be achieved by yourself or in the event the job is too big you can still make a booking for your GSM 50 right into a decent mechanic.
Gilera GSM 50 manual