Topic: Electrical on 75 CB750 SS - uh oh

[mboon85]

cb project continues. some time ago i removed all the wiring from the battery box because the box needed to be scrubbed clean. check. today my friend and i got it hooked up as it was before and went to turn it for the first time in my ownership and we didnt get anything. not even a light anywhere. Here's what i know:

the battery is new(shorai)  and properly hooked up/grounded.
all of the original wiring looks to be complete/unbroken.

what are my options? the bike sat outside for a while, so it seems, though not its whole life. Would i be better off purchasing a replacement loom? we're mechanically competent people but havent really messed with the electronics on bikes from the 70s and wouldnt know what to do aside from some minoring soldering. this is obviously a vague post, but i think the point is: clueless on where to attack electronics issue.

whats my first line of attack?

[MiGhost]

I am not overly familiar with the 750's, but there are a few things that could be the problem.
First, There should be a main fuse. Check to make sure it is not blown, or corroded.
Then make sure the ground wire is not corroded where it attaches to the frame\engine.
Finally make sure all the connections in the headlight bucket are clean, and tight.

[70CB750]

If you get no even light, than that's just electrical connection, no electronics involved.

You gotta do it the hard way, with a voltmeter check where the power still is and where it stops.  Sometimes you can even see a little smoke where the wire shorts to the ground.  I believe MiGhost is right, either fuse or connector.  Check if you get power to the main switch and where and if it goes from there, here are electrical schemas:

http://oldmanhonda.com/MC/WiringDiagrams/MCwiring.php#class

Do not leave the battery connected while you are not working on it, there can be a short that will kill the battery and/or set the bike on fire.

[MiGhost]

Do not leave the battery connected while you are not working on it, there can be a short that will kill the battery and/or set the bike on fire.

+++1
Definitely disconnect the battery until you know the cause of the problem!

[dgedinyte]

I'd start with the main fuse like MiGhost said. If your main fuse isn't blown you might have an open in the power wire that connects the main fuse to the key switch, or the ground of that connection. Also one of the wires at the key switch could be disconnected. Your problem sounds more like an open than a short.

[mboon85]

thanks for the help, gang. I'll be sure to keep this thread posted as we try to get her lit up.