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Ok so the problem isn't the battery. I took it to autozone and they charged it and told me that it was in good condition. When I got home I installed the battery on the motorcycle and I turned it on. Everything was fine until the next morning that I tried turning it on and the battery had drained again. Im probably going to take it to a motorcycle mechanic but I want to know if there is anything I can do before or try on the motorcycle before I take it somewhere.
 

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if the battery went dead overnight, then either the battery is bad (and the check they did on it was wrong) or there is something still drawing a current with the bike off....there are a lot of ways to figure out where the draw is coming from, but I don't know them heh....but I'm sure others will chime in with different tests you can run with a amp/volt meter to find it
 

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Unhook it from the bike overnight. Test it in the morning. If its dead its the battery at fault. If it is charged you will know its something on the bike.
 

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Third time's a charm.....

"Another possibility is that you have a parasitic draw on your bike which is bleeding down the battery. That doesn't normally happen very often on Harleys, unless someone installed an aftermarket accessory that's wired directly off the battery or fuse block, and doesn't get power through the ignition switch. "
 

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Swamp Rat Rider
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Try using a Battery Tender .. If don't get a Green light within 1/2 hour something is drawing on it big time or your Battery just isn't up to par regardless what they said .. I am a firm believer in a Tender even though Ride most everyday .. Nice to Start it every time at Home when has sitting a while even overnight with the Battery at Peak Voltage ..
 

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ZAMM Fanatic
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How to diagnose a parasitic drain.

Start by downloading a schematic for your bike. Print it out large using:

http://www.blockposters.com/

You're gonna need a working DMM. One that someone hasn't blown the internal fuse by trying to take a VOLTS measurement with the meter set on AMPS.

It'll speed testing up considerably if you'll make a four foot alligator clip out of some 12AWG wire, or 110V "lamp cord", with one of those small jumper cable clips that will clamp onto a battery post on one end, and a itty-bitty alligator clip on the other end - to grab onto your meter's test lead.

You're basically going to be disconnecting one of the battery terminals, putting your meter on (its maximum) 10A setting, and putting the meter's probes BETWEEN the battery post and the battery terminal you just took off.

do NOT hit the starter or turn on the ignition, radio, accessories, etc totaling >10A total or you will be looking for yet another replacement fuse for your meter.

then you dial the meter down to where you see the draw...10 A, 1A, 100mA...

Then you start pulling fuses from your motorcycle's fuseblock until you identify WHICH CIRCUIT is causing the parasitic draw...in the range of 50-300 mA, usually.

Sometimes the draw is on an UNFUSED circuit....

You can tell how bad a parasitic draw is by how fast it flattens the battery. A 50mA draw will flatten it in 2-3 weeks, 100mA one week, 200mA, two days APPROXIMATELY...

Next you'll inspect the wiring in that circuit looking for physical damage, chafing, modifications by a PO, etc.

Fuse in a cheap Harbor Freight multi-meter

 

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Female Rider
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If you don't have a meter just try Zippy's suggestion. Then you will know right away if it's the battery.
 

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I never trust Autozone's or places like that. Most of the kids working there are straight out of high school and probably don't even know how to read the readings, never mind tell you what they are saying. (not all, you do run into some smart ones). I had stopped at one autozone place because my check engine light came on and I wanted to get an idea what was wrong with it, so they hooked it up to their scan tool. They tried telling me it was my cat convertor, ect ect. Had them write down the code number so I can bring it to my mechanics attention, as he was away for a bit of time. Turns out it was only stupidity on the drivers part, as she forgot to put her gas cap back on.....Tongue in cheek.....And the code they wrote down confirmed it. They can't even look up the codes right in their books, nevermind diagnose anything...
 

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WadeNelson gave a good overview of how to check for a draw. I'll just add to disconnect your battery negative cable, and put your tester's positive lead on the battery negative terminal, and the tester's negative lead on the end of the bike's negative cable. Your Nightster can have up to a 1milli-amp drain. Anything over that is excessive.

Did you find out what that extra switch was for?
 

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there are several places that sell cheap amp gauges. You don't need to disconnect anything to use them. They clamp over a wire and display the amperage draw.

Place it on either the positive or negative cable coming off the battery with the ignition off. If you get any amperage draw you then need to find what is draining the battery, and that can be like a treasure hunt if you aren't experienced with electrical systems. I have seen relays stuck closed, wiring shorted, and aftermarket accessories install wrong.
 

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there are several places that sell cheap amp gauges. You don't need to disconnect anything to use them. They clamp over a wire and display the amperage draw.
Yeah, no. The cheapest clamp-on amp meter capable of measuring down to 10mA runs about $147.

[ame]http://www.amazon.com/GTC-CM100-Current-Clamp-Meter/dp/B001TCWL1E/ref=pd_cp_hi_1[/ame]
 

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Considering shop labor is a hundred plus an hour, 147 dollars is cheap. I suppose my perception of cheap and other is different, I should have clarified that.

My amp clamp has saved me a lot of time in the past.
 

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Pale Rider
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Great resource for all electrical matters on a bike: [ame]http://www.amazon.com/Motorcycle-Electrical-Systems-Troubleshooting-Motorbooks/dp/0760327165/ref=sr_1_1?s=books&ie=UTF8&qid=1412176658&sr=1-1&keywords=motorcycle+electrical[/ame]. I spent 3.5 years as an electronic technician, doing reverse-eingineering of circuits, and component-level repair. Even though I have professional training, and experience, I learned a very great deal from this book, and I was genuinely impressed with his explanations of electricity for the layman.

Electrical seems like Voo-Doo, but it isn't, once you understand it. This book can help you with that. Electrical troubleshooting can be quite tedious, and tedious translates into >$$$ out of your pocket. Your choice, but it is a tremendous help if you have this book as a resource. Cheers!
:coffee:
 

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Those big box auto part stores never seem to know. Get a good mechanic, but before that check your wires. It could be a pinched wire somewhere.
 
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