Motorcycle Repair: 1973 Honda CB500, key switch, rectifier

Question
Hi Rich,
I have a 73 (I think) CB500 and have had some issues with the electrical system. When I bought it, the previous owner mentioned that he put a new battery in and within a few days the battery would be dead, regardless of weather he was riding it or letting it sit. Any advice would be greatly appreciated. thanks!

Answer
Jason, you are looking for a current draw that is not associated with the key switch.  The only circuit that I can think of that would do this is the rectifier.  It sounds like the diodes in the rectifier have gone bad allowing current to leak back to ground.  You can check this by unplugging the rectifier and then see if the battery stays up.  You can also check the rectifier with a continuity checker.  It should have current one direction to ground and not the other.  

Regards
Rich