Question regarding battery connections

[The Voice of Reason]

I'm still working through my electrical system issues on a 1977 GS750. The charging system is checking out fine, and the battery is very good, but sometimes when I turn the key the lights come on, but when I hit the starter button everything goes dead.

I can then start the bike by wiggling the battery just a little bit; the lights come back on and it turns over and fires up easily.

I'm guessing some sort of loose connection. The battery terminals are clean and tight. I've cleaned up all of the connectors in the area, especially the three wires from the stator, but also every other connector I can identify and reach.

I have to admit I have not located and cleaned the engine case termination for the grounding strap from the battery. Is it on the bottom of the bike?

What else should I be checking? The solenoid?

As always, thanks in advance for all the help. I've learned a ton on this forum!

Voice

 

[lucabond]

You should be able to follow the ground connection from the neg terminal of the battery to the engine to fine the ground point. Did you check the connection from the plus side of the battery to the solenoid and the solenoid to the starter and clean both cable ends ? If that doesn't help move on to the starter and check the connection there and also where the starter contacts ground. Good luck.

 

[raistian77]

some times corrosion climbs into the cable itself where the ring terminal is attached. I would try new cables.

 

[GSJONNY]

I also had exactly the same occurance - i have run a temporary earth wire from the air box to the frame - its solved it till i can strip the box and find the dodgey connection/earth

 

[The Voice of Reason]

Excellent idea!

Excellent idea!

I also had exactly the same occurance - i have run a temporary earth wire from the air box to the frame - its solved it till i can strip the box and find the dodgey connection/earth

Not only does this seem like a simple stopgap solution, but it also offers information. If the problem goes away with a better ground, then I can be reasonably certain that the ground strap is the problem, right?

Or so I hope.

 

[koolaid_kid]

That is what I would do. Connect a good temporary wire to your negative terminal of your battery. Connect the other end to the suspect faulty ground area: Frame, engine are good places to start. This will lead to the determination of where the fault lies, then you can trace down from there. Whatever you do, don't go into parts replacement mode, where you are replacing parts until the issue goes away. A waste of time and of money.