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Discussion Starter #1 (Edited)
Hey all, I rode my bike to and from work yesterday with no problems. Came home, hooked it up the battery maintainer in the garage like normal, then when i went out to go to work this morning it wouldnt start. Any ideas on what it could be? Here is a short video of what it is doing. https://youtu.be/j4alBGtMmBo
I really dont think it is a dead battery as it is only about two months old and i keep it on the maintainer. Additionally, it was starting really easily yesterday, which is another reason i am so confused.

Thanks.
 

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the lights on the speedo are going out when you crank it

your battery is either dead, or you have a bad battery connection.

Have to ask, why are you hooking up a battery maintainer if you are riding it everyday?

Its possible the charger failed and boiled all the acid out of your battery.
 

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Discussion Starter #3
Hey KCW, thanks for the quick response, yeah, i hook up the maintainer whenever im not riding it. I havent had the time to really even take a look at it yet. I was in my office clothes so i could only do that video. I will have to check out the battery first.
 

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You only need to put the maintainer on the bike if its going to sit for a month or more, esp over the winter.
 

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Discussion Starter #5
Gosh, i get different info from everyone about the battery maintainer. I just pulled the cover off the battery and the battery is all swollen up. What is that from?
 

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that will happen if the battery is overcharged. The water boils out, and if it cant vent it can burst.

it could either be from the maintainer overcharging it, or your bikes charging system is putting out too much voltage (bad regulator).

Most batteries are sealed, and have no way to vent if they are overcharged.

I would wear safety glasses and take the battery out of the bike very carefully.

if the battery has swelled up its shot. Since you recently replaced it, that is a likely indication that something else is wrong with the charging system.

If you have a volt meter you can easily see how much voltage the bike is putting on your (next) battery, and also your maintainer.
 

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Discussion Starter #8
Well I feel like a moron for not checking everything out. I just ASSumed my battery fried from using my maintainer too much. But, after a road trip with my new battery it also swelled up and stopped working. On my way down to my destination I could smell something after I got off the highway but couldnt place the smell (it was the battery cooking to a nice crisp). I stopped to change into my business clothes near my meeting and it started with difficulty. Luckily it did start and I got to my meeting on time. When I got to my meeting I turned it off and tried starting it right away. Not even close to starting. With some help I was able to get it push started and get the 100 miles back home. About 30 miles from home the speedometer kept tripping out, going to 0 then to the correct speed. Got home and the battery is toast. Overall, I was very lucky on my trip.

Bottom line do I HAVE to get the bike started and go through the diagnostics or is it like 99.9% sure its my regulator/rectifier? This is the second new battery and was ridden less than 15 hours before it swelled up and gave up the ghost. I never put the maintainer on it with the new battery.
 

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My only thoughts would be over voltage or a dead short would do it. Since the bike does run, and gauges work (even sometimes), I would say it's not a short.

You should be able to check it on a bench using a ohms meter. generally 1 of the 3 will be bad, and not all 3, so you just see if one is different, inside the rectifier.
 

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It sounds like the rectifier is shot. When mine went I noticed my speedo and all lights weren't working. Pulled over and it was dead, not even a click from the starter, no lights. When I took off the battery cover my battery was hot to the touch. Took it home in my truck and had the battery tested. It was completely dead. Did some research and learned about the rectifier, then bought a new battery and checked the voltage across the new battery when the bike was running. It was over 19V, which indicated a bad rectifier that was overcharging the battery. Put in a new rectifier (easy job) and the voltage dropped to 13.5 - 14, which is normal. I've had no problems since.

There are plenty of cheap rectifiers on eBay - don't waste your money and risk killing another battery. Go with an OEM.
 

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when a battery is overcharged the acid is literally boiling - over 220°F. It must have blown a vent out after it swelled up, and that is what you were smelling: boiling sulfuric acid.

You are lucky it didnt explode under your butt. Twice!
 

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Discussion Starter #12
Yeah KCW, I agree. Its odd though, i didnt smell it on the first battery when riding, just a while after it was parked in the garage. Then on the ride home with the second battery I didnt smell it at all either while riding or when I got home.
 

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Some newer cars or SUVs have the battery in the passenger compartment
and families have died because of this - overcome by the acid fumes, and they kept driving till they died.
 

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Discussion Starter #14
While I was only able to find one example of what you are referring to KCW I have worried about the same thing. It is a common practice in tear drop campers to put the battery in the cabin area. I never understood that and when I built my camper I was sure to put it outside the cabin area and I tried to seal it off from the cabin as good as I could.
 

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every aircooled VW ever made had the battery under the back seat. I owned many when I was young, and have never heard of a VW overcharging its battery and boiling the water out - with over 15 million bugs made that is a pretty good record.

They only had two idiot lights on the speedo. One indicated your charging system has failed, which could mean the fan belt to the generator / engine fan broke and you better stop RIGHT NOW (beacause your air cooled engine is getting no air).

The other indicated you have no oil pressure, in which case you have about 2 seconds to shift into neutral and turn the engine off, or your bearings are history.

Maybe thats why no VW bug ever boiled out its battery, the engine was not able to keep running long enough to do it. Or maybe the charging system really was that reliable.
 

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Wonder if it is worth it to put in an over voltage relay, so if the voltage goes >16v it will disconnect the battery, or maybe the whole regulator from the bike.
 

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It should have been part of the engine monitor - over voltage is very easy to detect and turn the yellow light on.

Im surprised its not already in there.

Goldwings had a big problem with their charging system in the '70s. They put a volt meter on the 'dashboard'.
 
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