bike has no power

[kavan]

A few days ago my roommate and I put his 79 XS 1100 SF on the center stand to check the oil level. Once we were done with that he turned the ignition key to find no electrical power. He charged the battery for 24 hours and tried this again. The bike fired-up but lost power before he can get out of the driveway. Twelve hours later power was back (no charging this time) but again all is lost within a couple of minutes. All the fuses are okay, even the once in the headlight. Any ideas? thanks

[TopCatGr58]

Hey there Kavan,
Oh boy, lots of things to check and consider. Also, we don't know much about the bike, is it a recently acquired one, or is it one that he's had and been running for several years!?

How old is the battery? As has been stated before, it can sometimes hold a surface charge to show 12 volts, but doesn't have the depth of charge, may need to load test it, or replace if about 3 years or older(avg life span).

Also, even though fuses can look good, they can still be bad, did you actually take them out and test with meter? The clips that hold them in place can corrode and break causing intermittent conductivity!? His model doesn't have the separate MAIN fuse under the left side cover or seat, but follow the wires from the Battery, and check ALL connections for corrosion, take them apart, not just surface inspect!

Believe it or not, the ignition switch can also be suspect, exposed to the elements, it can also corrode, may need to take it apart and inspect, clean it's contacts!?

Okay, this will get you started, test and report back if not successful !?
T.C.

[kavan]

The battery isn't that old, and we took his battery out and put it in mine, and my bike started fine off of his battery. We then took my battery and put it in his bike, and no power--no lights, no anything. We checked all the fuses in the fuse box, and the two fuses that are behind the headlight (coming out of the keybox), both good. We're still in the process of checking all the connections, but none of them seem to have corroded or broken so far.

What do you mean by igintion switch? Is it the button in the same assembly with the kill switch? We took that apart, and there was a bit of rust--we cleaned it and nothing still.

Is it possible that is has something to do with the keybox itself? If so, how do we check that?

[randy]

Kavan,

There are not supposed to be fuses behind the headlight. My guess is that the previous owner did a bit of rewiring. This type of problem can drive you nuts because it's difficult to trace the rigged rewiring, it won't match the schematic.

[TopCatGr58]

Yes, Kavan,

The keybox switch is what I was refering to, just unbolt it from the steering head, unplug it and you can get it off, and you should then be able to see how to take it apart from underneath. Like Randy said, ain't s'posed to be no fuses in the headlight bucket, so sumpin' ain't right!!

With fuses in the bucket, makes me think the PO had some shorting problems and stuck some fuses in line to control things vs. FINDING the shorted wire, one that's gotten rubbed raw and is contacting the frame somewhere?

Also, you said that you took the right hand control set apart, cleaned up the contacts on the starter button, that's good. Did you inspect the contacts of the KILL switch!? Sometimes they can get buggy and if messed up, it WILL kill ALL POWER to the ignition system, but usually still leaves power to lights and such!

DO you have a voltmeter, or continuity/ohm meter?? Also, do you have the wiring diagram? IF you need the wiring diagram, let me know by emailing(not pm'ing) me and I can send you a FULL COLOR copy that you can use to trace down circuits!

Keep at it, you'll find it eventually!!
T.C.

[MAXIMAN]

I had a similar issue when I bought Maxine. The headlight was unusually dim. Occasionally while riding the whole bike would loose power...then power would return...just instantaneously.

Someone here told me first thing to do was pull the tank, headlight and seat where I could get to every electrical plug. Then pull each plug and clean thouroughly.

In the process I found the main ground wire from the electrical system to the frame was real loose. I tightened that up and the light got real bright. After that I never lost power again. You might check any grounds you can find.

Electrical problems can drive you nuts.

[chevy45412001]

fuses

like stated above don't just look at the fuses. I used a actual test light on mine,ohm meter will also work. Mine turned out to be a bad main fuse and IT LOOKED GOOD ,but was shot on the end by the metal cap ,WERE YOU COULD NOT SEE.give them a little tap with your finger tip while checking them,(reason for intermitent problem the wire in the fuse may be making contact slightly until jogged lose?)