Buying a used bike, electrical issues?

[gannon]

I've read through a few of the guides on here, nice amount of information! I'm nothing near a mechanic, but I'm giving it a try at least. Looking at getting a nice looking '81 XS650, but according to the owner it stopped starting in July this year. He said something about the main fuse, but the 4 fuses under the seat are all fine.
I tried to run through some things, figured it might just be the kill switch. Is there a way to test the switch without cutting through the wires leading to it? I saw the wires route through the headlight, then under the tank to someplace. I didn't feel comfortable enough to remove the tank of a bike I don't own though.
With ignition off the main fuse reads full voltage (3V for now), while other fuses read 0V like they should. With the ignition on however, the main fuse reads around 1.5V while the other fuses still read 0V. Is this a short somewhere or just because the dead battery can't handle the passive load?

Unfortunately I can't just buy the bike unless I can make sure it'll work (don't have the extra time or money to put into another project! lol). With any luck though I'll have a nice classic on my hands

 

[atomic22]

If it's the orginial fuse box, it could be bad connections within the fuse holder. Pop the fuses out and see if the holders are rusty. You didn't say if you check the battery voltage, but you should so you know what the readings should be at the main fuse.
The electrical system is not overly complicated, but it can get costly.
If it's that good of a deal, buy it and slowly work on it.

 

[xjwmx]

If you fix it at his place, its price will suddenly rise.

The first bike I bought was for sale because it wouldn't start, the owner said. I took it home intending to tear it apart. But before I got to that I noticed was it was out of gas. You might not believe it, but it's true...

Chances are it only needs a new battery if the guy is leveling with you. Whatever it is the odds are it won't take much to get it running. However it will still be a project to make it consistent and reliable.

 

[Travis]

It's probably more than just a fuse. If that's all it were, the owner would probably fix it and show you it runs so he could get more for it. Then again, maybe it's just a few simple things like a battery, fuses, and some connections that need to be cleaned and the guy doesn't want to deal with it. Since he doesn't want to deal with it, the price should reflect that it's a non running bike with unknown problems.. Not saying you shouldn't buy it, I'm just saying don't pay a premium because you think it's just a fuse.

 

[jamesgs4]

offer $150 for the parts bike.

 

[Ghetto]

We bought a bike that had 0 electrical working. We got it back and wiggled some crap around and had it running 10 mins later and all electrical working by itself by the end of the day. Was just a crappy fusebox.

 

[BZNrider]

A fuse should never have a voltage drop across it unless it is burned out. If he said 'it is just a fuse' I would bet that he has replaced it several times and there is a short somewhere that is burning it out. You mentioned 3V, is this the voltage across the battery terminals? I don't think these bikes will start with that little power, the stator needs more to energize.

Funny story: When I was test riding my 650, the turn signals and brake light went out. The price came down, and it turned out it was just a fuse!

 

[gannon]

Ah, yes I did check the battery voltage at the terminals, it was 3V.
The bulk of the wiring / fuse box looks original. Only new thing I see is a new taillight that has been installed.
There wasn't a voltage drop across the fuses, just happened that the voltage dropped that much when the ignition switch was on. The fuse holders did look fairly rusty, so that could be at least one issue. If I remember right, I only checked with my multimeter from the top of the fuses, not the connector side

Talked to the owner some more, seems he tried to get it kickstarted without any luck. I'd think that even with some electrical issues it should at least be able to kickstart, but maybe I'm wrong.

Also jamesgs4, I wish! He's asking 5 times that, although that's not too bad *if* it's not a big problem.

 

[gggGary]

an 81 won't kick start without 12 volts or darn near it. The TCI needs about 10 volts to make spark. It's your time of year as far as pricing goes, my shed is bulging because the deals just keep showing up, I would be embarrassed to say what I have picked up lately. Not free stuff, but late fall reasonable deals seem to be out there. The thing on XS650 is there is no singe "deal stopper" electronic part that turns the bike ot scrap. Some of the other bikes around have an ignition part that can't be had at any price it dies and "game over" there is not much that can die electrically on an XS650 that $100 and some detective work won't cure.

 

[gannon]

Thanks for the tips guys. It seems the issue was purely the fuse box (well, and dead battery!)
I checked it out again today and when I pushed on the main fuse the neutral light magically came on. After a quick jump the bike ran great. First on my to-do list is to make a new fuse box. Well, before that I have to get it home I suppose

 

[XSLeo]

Lots of people replace the fuse box with inline fuse holders. The blade type are better than the round glass type fuses. Not hard to do just cut the wires off the fuse box one set at a time. Red and red, brown and brown, red/white and red/white. You get the idea. Solder and heatshrink the joints.
Oh and welcome to our little group.
Getting the battery fully charged and load tested is a good idea too, this will tell you if the battery has any useful life left.

 

[gannon]

So, bike starts right up when jumped, but even on a fully charged battery it doesn't start most times. Guess I can grab a new battery, but only a few weeks left to ride around here, so maybe best to wait until spring. Wouldn't want to buy a new battery only to have it sit all winter...
Also if I try to start it for awhile it'll often backfire out the carb after I stop trying to use the starter it seems. Not sure what the deal is there, but again, I have practically no mechanical knowledge.

Edit:
Oh yeah, and just remembered. Seems the choke is locked up, can't pull it out for the life of me. Figured it's just a bit old/etc, will try to free it up later.

 

[gggGary]

the back fire after you let the start button go sounds like low battery voltage. Less draw with no starter lets the spark get stronger. Put jumpers on it to a NOT RUNNING car truck or lawn tractor. See how it starts and runs then. go buy a stinkin $32.00 battery keep it on a tender style battery charger about $20 at wally mart. A new battery is nearly always my first buy on a non running bike. take the old one with you to save messing with a second trip for the core.

 

[gannon]

Thanks Gary, seems that was the issue! I was worried that it was going to be something that required me to clean the carbs or something, so glad that I don't have to dive into that (at least not yet!)
Replaced a burnt out taillight, and now it's pretty much all ready to go. Hope for some warm weather so I can at least take it for a few rides before winter.
For now I just replaced the fuse box with another one just like it. Will be picking up some blade fuse holders sometime and doing a better upgrade.

 

[bdholsin]

Hey Gannon - Where in Houghton do you live? I spent 5 great years up there.

 

[gannon]

Well, actually in Hancock, but going to MTU at least

Spent today remembering how to shift and getting used to the clutch. Just a little bit of power if I let off too fast