Topic: DOHC Electrical Weirdness

[TomC]

Hi Jonnycbgood
     Stop
     Until your are measuring close to the same voltage at the positive battery terminal and the starter solenoid post there is no point in going any were else.
     You started the bike using the electric starter. This indicates a good charge in the battery and a good connection between the battery and the starter. The starter solenoid is in the middle of this good connection.
     I do not understand why you are measuring vastly different voltages at these two points that are or should be so well connected. TwoTired's idea of AC voltage caused by a bad rectifier sounds good. But I see no reason why you would measure reasonably good voltage at the solenoid and none at the battery. To check this disconnect the red with white tracer wire that goes from the regulator/rectifier to the starter solenoid. There should be a three connector plug. Just unplug it. Now start the bike and see what your volt meter claims the battery voltage is.
          TomC in Ohio

[jonnycbgood]

ignition coil rewire
http://www.cb750c.com/modules.php?name=Forums&file=viewtopic&t=2740

CB750K color wiring diagram
http://www.cb750c.com/modules.php?name=Forums&file=viewtopic&t=3631

I apologize for placing the posting in the wrong board thanks for correcting it.  The last test I grounded the common probe to the engine block and used the red probe and a spot tester.  The meter was set to 20V DC.  To tell you the truth I dont have a lot of faith in my meter seeing as I only paid 5 bucks for it.  I am going to borrow one from a friend that is calibrated and more accurate.  With that being said I tested the resistance across the copper windings of the rotor and got ~ 5.5 ohms.  i then unplug the stator from the R/R it had 5 wires - 3 yellow, 1 black (hot), 1 white (neutral).  i tested the resistance across the black and white and got off scale reading.  Across any of the three yellow wires was about 1.3 or so.  The housing and stator was covered with magnectic dust particles and the plugs is pretty dirty I am going to work on cleaning all the connections and the housing.  And then use a calibrated meter to see if any of the results change.  Any other ideas I am all ears?

TomC

The voltage at the battery positive post and the starter solenoid is the same and vary the same at all times.  I will try that new test and get back with the results.