New problem - battery

[Guest]

After being excited that the brake light on my bike was finally figured out I was replacing signal lights as well and was playing around with it. At some point I decided to go inside to relax a little.

I get back out and I left the keys in the ignition turned on.

No problem I think, battery was dead before, I take it off and bring it in - hook it up to the battery charger aaaaand...nothing.

I have 3 indication lights - AC power/Charging/Floating on my charger. Only AC power light is on. So I get the multimeter out and it's telling me there are 6v left on my 12v battery. So I think I should try again in the bike but nothing. No light at all - no power.

I am completely clueless at this point

[bonanzadave]

How old is that battery ? Water between the lines ? Connections clean ? Cables on the right terminals (it happens) ? I didnt remove mine this winter and it must have froze (-25f) so I just went and got a new one. On the charger now. $35 bucks is well worth it after having been stranded with a dead battery. Ever push start a 500lb bike .

[GateKeeper]

Charge overnight and see if it holds, or if you can get a battery for 35 bucks just do that, even a new battery requires proper charging,,,,my batteries usually cost me between 80 and 120 bucks.....

[bonanzadave]

I get mine at the fleet / farm store

http://www.fleetfarm.com/detail/road-runner-conventional-dry-power-sports-battery/0000000069708?categoryId=02262

[Patihubi]

I got this http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1 battery just in March.

Well the thing is that it doesn't charge, at least the light on my battery charger does not come up... THe connections are all ok, the battery is only 2 months old, that's the thing.

Could someone explain the 6v on the multimeter? Is that good/bad?


Btw. I also checked the fuse (only have one) and it's still ok.

[tkent02]

Sounds like a charger problem, not a battery problem.

[Patihubi]

Well, shouldn't the battery do SOMETHING with 6v on it?

But, I held the multimeter on the clamps of the battery charger and it gave me nothing - 0.01

[GateKeeper]

6 volts is low, and probably will do nothing, you need a full 12 volts or close to it...

sounds like the charger is not charging, then again I don't know what charger you have, and is it the correct one for the battery you are using ?

.

[Patihubi]

Yes, I charged the battery with it before.

It is similar to this one: http://www.amazon.com/WirthCo-20085-.../dp/B002JUNHKO Battery Doctor.

I have the clamp and the round adapters and both give me 0.01 on the multimeter...thats bad isn't it?

[Grimly]

The drawback of these modern microprocessor-controlled chargers is that they're too damn smart for our own good.
A half-voltage battery fools the charger into thinking it's a 6V bike battery and it won't treat it like a proper 12V one, and will only put 7.2V into it (or thereabouts).
You need to get the terminal voltage of the battery up a bit, to around 10.5V then connect the smart charger and it will treat it as normal from there on.
Two ways of doing this
1. Borrow an old-fashioned iron tranformer and rectifier charger and simply charge the battery up as used to be done for decades, or at least until there's sufficient voltage put into it.
2. Parallel charge the battery from another bike or car, but keep an eye on it, monitor the voltage at rest from time to time if doing it from a car - there shouldn't be any trouble, but you don't wan't to risk it overcharging.
3. Get another known good battery and connect it in parallel with the dud battery, then charge both of them on the smart charger.

[tkent02]

The drawback of these modern microprocessor-controlled chargers is that they're too damn smart for our own good.

An old school dumb charger is worth it's weight in gold or at least silver.

[Patihubi]

I wouldn't know where to borrow an iron transformer from And I have only access to our van with it's huge battery that does not have any indication if it's 12V. But it's humungus and not as small as our battery from the previous car (volvo) Could is just jump start the motorcycle with that if it's the same voltage?

Thanks for explaining that though, that makes a lot of sense! Could I somehow get a "not so smart" battery charger?


also, if the charger really "thinks" it is a 6V battery, shouldn't the indicator lamps say 'floating" when plugged in?



And I also still don't know why the clamps give me 0.01 on the multimeter

[Redman]

.
.But, I held the multimeter on the clamps of the battery charger and it gave me nothing - 0.01

Sometimes those battery chargers have some "reverse polarity" protection in them, they do not really turn on until it sees you have it connected to battery in proper polarity, so it needs to see some voltage in proper polarity before it really turns on. THis is so if If connected backwards (reverse poliarity) it doesn't turn on.

So if you were measuring voltage on charger without ti connected to battery, maybe it really wasn't turning on.

[tkent02]

Thanks for explaining that though, that makes a lot of sense! Could I somehow get a "not so smart" battery charger?

It will be the cheap one on the bottom shelf.

Second hand store might have one.

[Grimly]

I wouldn't know where to borrow an iron transformer from And I have only access to our van with it's huge battery that does not have any indication if it's 12V. But it's humungus and not as small as our battery from the previous car (volvo) Could is just jump start the motorcycle with that if it's the same voltage?

If it's 12V, sure. But make sure it's properly charged up itself, only do a direct parallel jump connection, don't have the car running.

Thanks for explaining that though, that makes a lot of sense! Could I somehow get a "not so smart" battery charger?

Yes, there are still plenty around, even if they've dropped off the shelf a bit. A trawl on ebay or fleamarkets will find one for a couple of bucks.
Here's the kind of thing to look for..
http://tinyurl.com/old-car-battery-charger

also, if the charger really "thinks" it is a 6V battery, shouldn't the indicator lamps say 'floating" when plugged in?

I can't answer that without knowing what charger you have and how it's supposed to behave. There's always the chance it might be defective, or the battery has dropped too low so the charger even supposes that it's a 6V beyond saving.

And I also still don't know why the clamps give me 0.01 on the multimeter

Umm... dunno Again, I don't know what meter you have and what its characteristics are. Mine, for example, gives some fairly dumb and uninformative readings when it's out of range.