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Discussion Starter #1
I have a short apparently in the lighting circuit. I'll have the engine running and then the tach drops to near 0, and the engine will quit at times. Sometimes on the road, the tach will jump around and occasionally I'll get a "pop" sort of sound in the exhaust along with a loss of power. Now, if I turn the key to turn the lights off, it clears up and no problems. So, am I stuck with tracing every wire to try and find the short, or is this a common problem with maybe a direction I can start in. I thought it was my tail light, since I had it off a few months ago, but I've covered every base I can on the tail light. Electrical glitches are a real pain in the rear. :boxin:
 

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not necessarily a short

SInce this "Gremlin" appears only with the lights on it may be a low voltage situation. Electronic ignitions demand good power if your lights are taxing a poor charging system the motor will cut out and possibly kill the signal to the tach.

Have your battery, and charging system checked.
 

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I had that same problem with a sporty and ended up being the key switch itself..hopefully this helps you... look at the wires on the back mine was corroded and ready to fall off..
 

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Discussion Starter #4
Thanks for the tips. I checked the battery, we're good there. I did a resistance check on the coil, and got 3.0 ohms on the small terminals, and 11,800 on the bigguns, so I think that is good, from what I've been able to dig up. I'll have to check the switch tomorrow after work and see what I come up with there.
 

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Don't forget to check all of your grounds. The source of many an electrical gremlin.
 

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Both times the tach has jumped around on mine, it has been the wires going to the coil. First time they were loose, second time a connector was cracked. If those wires (3 of them, if I remember right) are tight with good connections, trace them to the other end. Check every wire and connector on the back of the key switch. A multimeter or a 12V circuit tester is your friend here. Learn how to use beeper diode, pretty simple really. If you don't have a manual with wiring diagram, now's a good time to get one.
 

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Discussion Starter #7
Thanks for the suggestions. Looks like I have my weekend lined out :beer: I'm sure I'll be back on if I get in over my head.
 

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I just posted this to your intro thread, but just in case you don't see it there. This probably won't help but I had a similar problem. My gas gauge was reading full all the time. I didn't pay it much attention until one time the bike wouldn't start and a lot of other stuff wasn't working right. I guess there was a short in the gauge. There's a lot of stuff on that circuit, including the starter, bad idea. I fooled with it for a couple of days, finally just cut the wire to the gauge. It's been all good ever since. My trip odometer works fine. Good luck.
 

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horseman, do you have a fuel management system on the bike? if so, remove it and plug the ECM back in just to rule that out.
 

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Discussion Starter #10
No ECM on this one. Just the basics. The only electronics on it other than the lights and starter and ignition, is the tach. No speedo, no odometer, no fuel gage.

Now that I'm thinking about it though, there is a neutral indicator light that stopped working some months back. I wonder if that could be it.... maybe the wire came loose and is shorting on something...

horseman, do you have a fuel management system on the bike? if so, remove it and plug the ECM back in just to rule that out.
 

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when you say "loss of power" are you referring to HP or you lose all electrical power?
 

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Discussion Starter #12
what usually happens is the lights will dim a lot, the tach starts jumping around, and there is a noticeable drop in HP along with a popping sort of sound from the exhaust. It's intermittent and usually just lasts for a second or two at a time, though sometimes there are several of these little instances in fairly quick succession.
 

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Discussion Starter #14
Ok, I checked the voltage regulator and I'm getting a small voltage out of it when it's unplugged. So, I'm off to get a new regulator. That hadn't even occurred to me before. I guess I always just figured if the regulator was bad, there wouldn't be this intermittent problem and it would be all the time. Learn something new everyday. Thanks for all the help yall.
 

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Discussion Starter #15
:confused:

Took the bike in to have it checked out, just to make sure I was checking things correctly. The HD dealer said it was the stator that was going out, so that was replaced. Rode it home and was fine. Next morning, same thing as before. Not quite as bad, but still doing it. Then on the way home it was back full on. Also, if the brights are on and you turn on the turn signal, the indicator light for the opposite signal flashes. Only when the brights are on though. wth?
 

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Did they replace the regulator too? they should have, check the voltage at the battery at 2000 rpm, should be 14.5 volts not higher than 14.7 or so
 
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