If you want to conduct repairs on your Husqvarna 125 WRK then it is always a good idea to own a Workshop Manual for a reference in the event you want to know how to remove a particular component such as the Gearbox and fit it again adequately.
Husqvarna 125 WRK Workshop Manuals will give identifiable diagnostic details for your car so if something is wrong it helps you identify what the issue is and how you can repair it. You can then analyse if this can be done yourself or if the job is just too big it is possible to make a reservation for your 125 WRK in to a decent garage.
Husqvarna 125 WRK manual