XS400 Ignition Issue

[jake21]

Hey guys. My name's Jake (hence Jake21)
I just picked up my first 1980 XS400, and im having some issues. When I initially got it, the ignition functioned fine, the clutch worked ok, and it was able to go into gear no problem, but the battery was super low. I replaced the battery, and everything worked ok (besides for the handelbar starter, which never worked, ive always had to kickstart it). My friend who knows bikes came over to help me with some of the noise that was going on in the starter. Right before he left, he showed me how to use the key to lock the bike. After he left, I tried to unlock the wheel, and suceeded, but when i fullly turned the key, there was no power to the bike. No lights, horn, nothing. I tested the battery, its fine. Im thinking i need to replace something in the igntion, but im unsure what Im looking for. Anyone have this issue before?
Thanks a bunch.
Good to be part of the group.
Have some mercy by the way, I am a newbie!

 

[Old Mose]

Hello Jake, My XS ignition is on at the first click and accessory on the second click, It won't do anything on the second click. Is it possible yours works that way to?

 

[jake21]

Hey Mose. I don't think so, because I've been turning the key the same way now that I was turning it before. Thanks for the suggestion though.

 

[BBS360]

Contacts could be worn or blocked somehow.
My ignition cylinder was full of dead spiders when I took it apart....
Doesn't take much to remove the cylinder, disassemble it, and clean the guts.

 

[jake21]

Hi BB. I took it apart but it was clean inside. I may just need a new one, but I dont want to buy one until i test this one for power.
Thanks

 

[jake21]

Just to update...I tested voltage coming out of the ignition with a voltmeter, nothing doing! There is a bit of resistance from the ignition to the battery area, so Im assuming the connections are ok. Should I replace the ignition switch? I just don't want to shell out 30-40 bucks if that is not really the issue.
Thanks

 

[BBS360]

So far it doesn't sound like it should require replacing.
Seems like something must be stuck or blocked or maybe missing.

If the contacts are clean and not overly worn it should be OK. I seem to recall there should be two spring loaded copper contacts that push against the plate below that has the wires connected.
Should be a spring for each contact that push them down.
As long as nothing is missing and the contacts are making good electrical contact with one another it should work.

I feel like there's something in there that I'm not quite remembering. There's a mechanism that engages/disengages just as the key is turned just past the first apparent stop in one direction.
I'll have to dig out my ignition cylinder to have a look. It's in a box right now, fully refurbished and waiting to be reinstalled...

 

[jake21]

So it turns out that the battery I had just installed new from Advance Auto lost its charge overnight, so the reason there was no power was because...there was no charge on the battery. As to why the battery lost its charge, I;m not sure if the battery itself was defective or something else....but I will let yall know. Thanks everyone for your help.

 

[kshansen]

I'd put a full charge on that battery, per the instructions that should have come with it, then let it sit over night not hooked to anything. If it again looses it's charge take it back to Auto-Zone. If it holds its charge you need to see what on the bike is causing a drain on the battery.

 

[jake21]

Out of the frying pan into the fire! Turns out my charging system is shot...
So now I'll be attempting to determine which parts or wires need replacing.
Thanks guys

 

[BBS360]

What are your symptoms, other than a dead battery?

It's generally a pretty robust charging system, despite the numerous threads on charging problems.
Do the resistance checks on the stator and field coil. The wires to them go right by the drive sprocket and are vulnerable to damage and contamination.

 

[jake21]

Thanks BB. Im gonna check them now.

 

[jake21]

So i did all the resistance checks, on the stator, coil, and rectifier, and everything came out OK..so Im thinking maybe the positive connection from the rectifier to the battery is shorted. If thats OK, I think I'll need to remove the rotor. For that, I need a big bolt (16mm, 1.5 thread). Looking around for that now.

 

[BBS360]

There's nothing electrically connected to the rotor. Anything wrong with the rotor would have to be pretty catastrophic for it to be the problem.

Not quite sure what you mean about the rectifier to battery connection.

If everything you mentioned is OK I'd be considering the regulator.

 

[danalpatt]

so i guess my question is did u voltage test well it was running... sorry i did not read all posts
next question when battery is fully charged did u try putting a voltage meter in between the pos connection at battery and the pos connection at bike then turn the voltage tester to amps and check the amount of power being drawn well bike is in off position ... it should be really really low possibly even 0 amps pulled not exactly sure

 

[jake21]

BB - I mean the red wire connecting the battery to the voltage regulator, maybe the wire is frayed closer to the battery? Im going to check it now
danalpatt - I did do voltage test while running, and it just kept dropping, i also looked at the amp reading while in off position and it is 0.
Thanks for all the advice guys.

 

[jake21]

Sorry BB - i actually meant the red wire connecting the Rectifier to the battery. So yeah, I ran all the tests, and it seems my voltage regulator is shot. Is there any way to do a resistance test on it? Or do i assume it just needs to be replaced based on process of elimination?
Thanks guys.

 

[danalpatt]

Sorry BB - i actually meant the red wire connecting the Rectifier to the battery. So yeah, I ran all the tests, and it seems my voltage regulator is shot. Is there any way to do a resistance test on it? Or do i assume it just needs to be replaced based on process of elimination?
Thanks guys.

take a picture of ur rectifier and tell me what wires u want me to test i have a 84 so not sure if it is the same so take a picture and if it looks the same as mine ill test any wires u want tested

 

[BBS360]

Is there any way to do a resistance test on it? Or do i assume it just needs to be replaced based on process of elimination?
Thanks guys.

It's electronic. There isn't any resistance test to do. You could compare yours to a known good one, under various rpms and battery charge levels, observing what it does, but basically it works or it doesn't work.
These are out of the Haynes manual:

 

[danalpatt]

well that sucks