If you choose to accomplish adjustments for your Sym GTS 250i then it is always a good idea to possess a Workshop Manual to use as a guide in case you need to know the right way to remove a specific component like the Wheel Bearing and match it again in the correct manner.
Sym GTS 250i Workshop Manuals gives you certain diagnostic guides on your vehicle therefore if something is wrong it will help you identify what the problem is and some ways to fix it. You will be able to determine if you can do this on your own or in case the job is simply too big you are able to make a booking for your GTS 250i in with a nearby friendly mechanic.
Sym GTS 250i manual