If you want to do auto repairs for your Triumph T 140 E Bonneville then it is always a great idea to own a Workshop Manual to keep just for reference in the event you want to know the best way to remove a certain part including Wheel Bearing and match it again effectively.
Triumph T 140 E Bonneville Workshop Manuals gives you specified diagnostic information for your car therefore if something is wrong it will help you work out what the problem is and the way to make it better. After that you can evaluate if you can do this yourself or if ever the job is too big you could make a booking for your T 140 E Bonneville into a trusted repair garage.
Triumph T 140 E Bonneville manual