ignition trouble shooting help needed

[williwm]

hello, Needing info on a problem with no spark condition on 78 gl1000. I have a weak to nonexistent spark on 3-4 cylinders. I get app. 12 volts to the points on 1-2 points wire but only 5 volts on the 3-4 wire. This is taken with the points and condensers unplugged from the system. Coil failure in the primary side is a possibility but would most likely result in a no voltage reading. So I need to check the wire and any connecters between the points and coil.
Problem is getting to that wire. I was going to remove the coil pack to be able to check the wire(and could also ohm the coil) but the left bottom bolt is gonna be hard to get to. second thought is to remove the radiator to access the wires from underneath. any tips to help prevent me saying a lot of bad words?

[williwm]

well, maybe a simple fix. In my removing some of the wiring connectors I decided to wiggle all that I could access and voltage increased. Looks like a connecter on the plastic housing under the left tank cover is the culprit. Checking the wiring diagrams on this site identifired the connecter. I'll give all a good cleaning. thanks for that wiring diagram.

[Whiskerfish]

Yea this does not sound right. The odds of a single wire issue in that wire bundle are really slim. Without the engine cranking the voltage drop across the Ballast will be several volts so you seeing 12 volts is suspect unless someone was holding the start switch while you did the test? I am not doubting your word but there should not be 12 volts on either of the wires for the points with the ballast in play. I would check the power at the top and bottom of the Ballast as a first step.

[williwm]

The 12 volt reading was taken with the points unplugged so the resistor was not under a load. Cleaning the connecter fixed the problem with the 3-4 not firing. The ballast resistor is doing it's job as the voltage on either point set measures 4.5 volts with the enging running. Again thanks to NGW for the wiring diagram, wealth of info here.

[Rat]

Gotta love it when it comes together

Gord