If you need to undertake maintenance for your Hyosung RX125SM then it is always recommended to possess a Workshop Manual to keep just for reference should you want to know techniques to strip off a certain part for example Gearbox and install it again in the correct way.
Hyosung RX125SM Workshop Manuals gives you detailed diagnostic guidelines for your car or truck therefore if something is not working it will help you figure out what the problem is and tips to resolve it. You can then evaluate if you can do this by yourself or that the job is simply too big you are able to make a reservation for your RX125SM in with a decent mechanic.
Hyosung RX125SM manual