80 CB750K Not Charging with new parts!

[BullMagnum]

Newbie here! Any help appreciated.
New Battery, New Stator, New Reg/Rec, new Rotor.
Checked all parts with meter, they are in spec.
Cleaned all frame grounds, still battery does not charge!
Starts at 13.13 V, turn on kill switch still 13.13 V, turn on ignition goes to 11.8 V???
Start bike stays @ 11.8 V. Turn igniton switch off goes to 12.5 V.
Each start gets lower and lower Volts until bike will not run.
Could it be the wiring harness?
No corrosion on any connections.

[blackhawkrider]

There is most likely a short in one of your systems. Best way I know of to find the system responsible is to remove one fuse, check it the way you where doing it replace the fuse and move on to the next fuse until you find the problem system. When you find which system then all you have to do is check all your hot wires for continuity where there shouldn't be. Like between hot wires and your frame/ ground. Hope this helps, I understand how frustrating finding electrical problems can be but it sounds like you are almost there.

[BullMagnum]

Checked without each fuse still nothing?
Any ideas?
Could it be a bad wiring harness?

[wantoride]

For what it's worth, I'm a newbie with the EXACT SAME problem. I purchased a 1980 CB750K six wekes ago from a small local motorsports shop. He first replaced the Regulator Rectifrier without doing any testing. I found two simular cases, one with ( ElectroSport) a resourse for Trouble Shooting Motorcycle Charging Systems. I gave these to the shop to help him find the problem with my bike.
See links
http://www.charter.net/google/redirect.php?to=aHR0cDovL2VuLmFsbGV4cGVydHMuY29tL3EvTW90b3JjeWNsZS1SZXBhaXItODM3L0hvbmRhLUNCNzUwLUstMTk4Mi5odG0%3D&context=results.1&count=2&_LT=GRLK_GBARGLBLX_OGRSR
Then he replaced the Stator. and finally the Rotor. I took it for a short test ride Saturday and it ran terrible. It was backfiring when I got on the throttle, and was reving at 2500-3000 RPM at idle. I drove it home and put the battery charger on it once more. This time it indicated that it was charged. I attemped to ride it again,  cranked the starter for about 7 seconds with the run switch in the off position.  Then turned it on and tried again. The starter turned over slow but the engine started. I turned it off, and tried again. It would not turn over.
I charged the battery overnight.  Today I put it on it's rear stand and started the engine. With the  lights on high beam, and the idle adjusted to 1,100 RPM, it ran exactly 30 minutes then stopped. The battery was discharged.
 Did you find the problem with your bike yet?  If not I hope this helps.

[BullMagnum]

Found out the problem!
Negative battery cable was corroded inside!
Copper wires had all turned black with white and green corrosion powder caked in.
Replaced wire and charging system works again.
Wish I had checked this first before I replaced every other part in the charging system

[Seacat]

I had much the same problem with my bike not too long ago. The battery would charge from a tender but not from the bike. Everything was checking out just fine. I was pulling my hair out.

Then one day as I was checking everything over again I found a stud on the back of the Master Fuse Block was naked. No nut. The Wire Ring had popped off. I put the ring back in place and found another nut. Once it was tightened down it was working just fine.

Cat