If you choose to undertake maintenance to your Yamaha TDM 850 then it is always a great idea to own a Workshop Manual to keep just for a reference in the event you need to know the best ways to remove a particular part like the Exhaust and fit it again successfully.
Yamaha TDM 850 Workshop Manuals are able to offer certain diagnostic details on your vehicle therefore if something is faulty it will help you identify what the issue is and methods to fix it. After that you can decide if this can be done on your own or in the event the job is simply too big you can actually book your TDM 850 into a local car garage.
Yamaha TDM 850 manual