If you want to perform fixes on your BSA B 25 Star then it is usually a good plan to have a Workshop Manual to use as personal reference in the event you want to know tips on how to strip off a certain component such as the Exhaust and install it again successfully.
BSA B 25 Star Workshop Manuals offer you certain diagnostic facts for the vehicle therefore if something is faulty it helps you discover what the situation is and some ways to fix it. You can then decide if this can be achieved yourself or if ever the job is simply too big you are able to book your B 25 Star in with a decent repair garage.
BSA B 25 Star manual