If you wish to execute fixes for your KTM 125 RS then it is usually a great idea to have access to a Workshop Manual for personal reference in case that you need to know the right way to remove a specific part for example, the Brake Discs and fit it again in the right way.
KTM 125 RS Workshop Manuals gives you precise diagnostic guidelines for the automobile so if something is wrong it can help you find out what the issue is and the way to fix it. You will be able to evaluate if this can be achieved on your own or in the event the job is just too big it is possible to make a booking for your 125 RS into a nearby friendly mechanic.
KTM 125 RS manual