Hello! I have a 1976 Honda CB550 that is giving me some trouble.?

[Buster Brown]

Start with the battery terminals and the ground. take them apart, clean them, coat with dielectric grease and reassemble, making sure they are tight. Move to the battery ground, and to the starter and starter relay connections.

Look at the starter switch as well. The contacts inside the switch may be dirty, or worn down so their connection is uncertain. It may be time to replace the switch, or see if there isn't some rehab work you can do with some contact cleaner or solder.

You can check out your battery pretty easily while you are at it. A fully charged battery should read about 12.6v at rest, should not drop below 10v while cranking, and should read about 14v when charging, maybe 13.1v at idle.

The problem you are facing is that your once-reliable Honda electrics, which might have still been pretty good at age 20, are now well past 30. Oxidation and dirt are finding their way into the connections, and plastic insulation is getting brittle.

 

[Firestormer]

Sounds like the connection between the battery negative and the frame.
You need to take it off, clean the surfaces and reassemble tightly

 

[Ben]

I recently had a local shop clean the carbs out, and the bike was running ok. It would start when I wanted to use it. The day after I brought it home, I could turn the ignition on and the lights would come on like normal, but as soon as I would try to start it everything would go black. I turned the key back off, and then back on and its still dead. I thought it may be a problem with the battery so I replaced it, but the same thing happened, lights came on initially then nothing. Any suggestions where to start looking? It can't be a fuse because it comes on initially. I feel like finding the problem could take a very, very long time.

 

[Live to Ski]

First, the carb issue has nothing to do with the electrical issue. With the exception of that when removing and reinstalling them a wire or wires were "disturbed". Its likely they took the tank off too, so follow the wiring harness along the left side of the frame tube just beneath the tank and in the area of the carbs.

I had an unusual electrical problem with my 75 550 and found a short (insulation had rubbed through) in the wiring harness up near the steering head under the gas tank.

At first, the bike would run fine, headlight on but would die every time I turned the handle bars to the far left lock. Then the bike would be running fine and as soon as I turned on the headlight...dead. So that made it a little easier to trace the problem.

Electrical problems can be a b*tch. You need to systematically trace it out. It helps to have a wiring diagram. They are available on line.

Google 1975 cb550 owners manual.

And register at sohc4 like Cettoman said.

 

[guardrailjim]

The battery cables may not be making a good connection.
Remove the cables from the battery.
Clean them with a wire brush and contact cleaner.
Tighten the battery bolts with a wrench, not a screw driver - a screw driver won't get them tight enough.

 

[Cettoman]

In addition to what Buster Brown said, join the Honda 4 owners forum. After you find out what is wrong, you will need parts. These guys either have them laying around or know where you can get them. They also know quick fixes and short cuts to get you up and running.
I wish I had the internet back in '74 when I owned my '72 CB750!!