Motorcycle Repair: 1980 Honda CB650, regulator rectifier, yellow wires

Question
I read a question on here that you anwered that sounded just like the one I have. BUT, here is my situation. I just bought a 1980 honda CB650 and watched the guy ride it around. he told me there was a part that needed to be replaced which was the Regulator Rectifier (?). So I bought it and put it on. well now every time i turn the key on the fuse on the silinoid blows. But if I unplug the regulator rectifier and put a new fuse it in, it starts and runs fine but only until the battery is dead. well today i was running it with it unpluged for a bit and it just ran really bad and wouldnt idle right. it died if I let off the throttle or choke. I do know I'm the 3rd owner of this bike and it has sat for quite a while and I was was praying you would be able to help me out. please email me at smithjosephd@gmail.com when possible. thank you
joe smith

Answer
Joe, did you get the new reg/rectifier from Honda or was it an aftermarket unit? Or was it a used part?  Go here to see the wiring diagram for your bike:
http://oldmanhonda.com/MC/WiringDiagrams/MCwiring.php#class

If your new part blows fuses, either there is another wiring problem in the circuit (grounded wire) or the "new part" is defective. If you still have the old part, does it do the same thing... blow fuses? If not, then the new unit has an internal short. Try to unplug the connector to the stator (yellow wires) and see if it does the same thing. If not, then the stator could be grounded or the rotor windings shorted out. There is no other reason, assuming that nothing else has been done to the wiring harness/bike in the way of add-ons, to make a 30amp fuse blow out.

They are definitely battery-powered ignitions, so fix this problem soon, or the battery will need replacing as well, because they don't like big charge/discharge cycles for too long.

Bill Silver