If you wish to do fixes on your own KTM 200 EXC then it will always be recommended to have access to a Workshop Manual for a reference should you want to know the way to take off a particular component including Gearbox and fit it again safely.
KTM 200 EXC Workshop Manuals offers you identifiable diagnostic information on your automobile so if something is not working it will help you find out what the situation is and ways to fix it. You can then decide if this can be achieved on your own or if ever the job is too big it is possible to make a reservation for your 200 EXC into a decent mechanic.
KTM 200 EXC manual