Battery Charging? New to that!

[yticolev]

First thing I would do in this situation is try a bump start too. I'm surprised it was only mentioned by tooblekain now. It may be tough with the battery at 7V, but I have bump started cars that were so low that they could not run the radio with the motor off.

How to bump start? Ignition on, put in 3rd gear, hold clutch in, push the bike as fast as you can (preferably on a downslope), jump on and pop the clutch.

If that failed, I would have no issue to jumping from any car, running or not. A voltage surge from starting the car will go from 12V to 14V max, not enough to fry anything. There cannot be a substantial current surge over what is needed to turn the motor over absent connecting the jumper cables together.

 

[L.B.S.]

Interesting! Doesn't make much sense....

seems like it should be:
00 = 0%
06 = 50%
12 = 100% (on a 12V battery)

Perhaps I don't understand percentage when applied to a battery?
How is 12.2 50% of 12.6? (I suppose it doesn't matter....)

Things can be deceiving when looked at with a "it should be" mindset applied with no other base info on the subject. That's why quotes taken out of context, can be spun almost completely opposite of what the original intent was.

Don't think of a 12V car/bike battery as a single entity thing, producing 12v.

It's really, six individual wee little batteries or "cells", @ 2.1 volts each, together adding up to an ideal of 12.6 volts.

If say, one cell out of six was semi-knackered for example, then it would be effecting the total produced voltage by more than a simple 0-100% ratio of voltage from your 0,6,12 numbers. All it takes to drop down below 12.6V is a few millivolts between a few of the cells being impaired. (Sulfation, physical damage between internal connetions, the energy being drained to fast/too much without replenishment, etc.)

 

[yticolev]

Voltage, current, and capacity (amount charged) are different.

 

[StratTuner]

How to bump start? Ignition on, put in 3rd gear, hold clutch in, push the bike as fast as you can (preferably on a downslope), jump on and pop the clutch.

I't's 95 outside on it's way to 100. I'm 50 years old, and the NC weighs just about 500lbs.
The numbers are all against this, but I'm glad to hear folks are strong enough to attempt feats of strength like that one!

 

[StratTuner]

Voltage, current, and capacity (amount charged) are different.

yes, they are different. one starts with V and the others start with Cu, and Ca respectively.

 

[L.B.S.]

yes, they are different. one starts with V and the others start with Cu, and Ca respectively.

bahahaha

 

[dduelin]

Its possible the tender did not even recognize the battery due to extremely low standing voltage so it did its thing for a while then cut off the charge current. I think the Jr. tender has too little output to charge a deeply discharged battery. The logic runs a charge cycle for about eight hours and if the voltage has not risen to a certain point it shuts off the charge current to prevent a dangerous condition. Tenders are designed to maintain healthy batteries not recharge them. For that you need a 1.25 to 2 amp charger.

 

[L.B.S.]

Its possible the tender did not even recognize the battery due to extremely low standing voltage so it did its thing for a while then cut off the charge current. I think the Jr. tender has too little output to charge a deeply discharged battery. The logic runs a charge cycle for about eight hours and if the voltage has not risen to a certain point it shuts off the charge current to prevent a dangerous condition. Tenders are designed to maintain healthy batteries not recharge them. For that you need a 1.25 to 2 amp charger.

Quite so, I hadn't thought Stat's battery was *that* dead.

To be honest, if the price of a new battery wasn't too dear compared to a Charger, I would probably go out and buy a new battery and be done with it, versus now going out and buying a bigger/better charger to get this battery back up, only to have the battery still a little sickly and possibly shortened future life, but that's just me.

I haven't bought a new battery or a new charger in decades, so I'm not up on the relative costs of things nowadays...

 

[yticolev]

I'm 58, and I've bump started my PT Cruiser half a dozen times (it eats batteries) by myself. A 500 lb motorcycle is a piece of cake! Even a small slope will make it much easier. Or a second person helping to push.

Do you have AAA? They'll come and jump your bike.

 

[VTHokieAg]

I work for a major battery company and I can reassure you that 7.35 volts is a seriously discharged battery. As someone stated 12.0 V is still discharged even though everybody refers to automobile/motorcycle systems as 12 volt. You are looking for a reading of ~12.50 - ~12.75 volts on your voltmeter.

 

[dduelin]

I could do this, I have done this, but Strat may not be comfortable doing it. Hook up the car battery to the bike battery (car off). In a way electricity is like water and current will flow from a charged battery to a discharged battery (both 12v of course) trying to equalize the voltage, or level, to use the water illustration. The car batt will be about 12.6 or so and current will flow into the +/- 7 volt one. If he checks the voltage of the bike batt at this point the voltage will be 12.4 to 12.6 because the meter "sees" just one battery that is healthy.

Anyway, start the car and let it idle and just leave it hooked up like this for 20 or 30 minutes. Use the alternator on the car to charge the bike. Leave the motorcycle off and don't try the starter. It won't hurt anything to let the idling car charge the combined batteries. Then separate them. The flat battery will have enough voltage by now to wake up the tender and perhaps start the bike. The tender Jr. then will probably have the chutzpah to finish the charge overnight.

If you want to go riding right now hook up the car battery as above and start the motorcycle and ride off.

Just as an aside, system voltage under 10 volts or so won't energize the fuel pump and the fuel injection system won't work so forget trying to bump start the bike. If you turn the key ON and don't hear the whirr of the fuel pump and click of the main relay the bike has no chance of starting.

 

[belinda k]

The Battery Tender Jr. is basically a "maintainer". It will work fine for maintaining a charged battery. But a discharged battery will need a jump start or a battery "charger". May need to remove it and have it checked if it can't be jump started or revived with a battery "charger".

 

[StratTuner]

Almost two hours later, and the battery reading is the same: 7.35....

it's not charging....time to get another one.

 

[StratTuner]

The Battery Tender Jr. is basically a "maintainer". It will work fine for maintaining a charged battery. But a discharged battery will need a jump start or a battery "charger". May need to remove it and have it checked if it can't be jump started or revived with a battery "charger".

the instructions say it can charge a battery not just top it off...just takes a long time

 

[StratTuner]

I'm 58, and I've bump started my PT Cruiser half a dozen times (it eats batteries) by myself. A 500 lb motorcycle is a piece of cake! Even a small slope will make it much easier. Or a second person helping to push.

Do you have AAA? They'll come and jump your bike.

Uhh... I barely trust the mechanic at the Honda Dealer. It doesn't seem wise to let some guy who drives for AA touch my NC.

You're a stronger man than I am.

 

[belinda k]

I would find an All Purpose battery charger with multiple settings......
Try a 10 amp charge for 6 hours and then measure voltage. May need to repeat.

 

[yticolev]

Uhh... I barely trust the mechanic at the Honda Dealer. It doesn't seem wise to let some guy who drives for AA touch my NC.

The difference is that he jumps vehicles all day long. Since you are afraid to do it, it makes sense to use a pro. You may be happy to learn that they use a battery pack to do it, it isn't hooked up to their vehicle.

 

[dduelin]

Almost two hours later, and the battery reading is the same: 7.35....

it's not charging....time to get another one.

Did you understand anything in this thread? You don't need a new battery. Try buying a $40 1.25 or 2 amp charger and trick it into seeing your battery. You can always use the charger again in the future. Or spend three times that for unneeded battery? Makes no sense.

 

[StratTuner]

Since you are afraid to do it, it makes sense to use a pro.

I am not "Afraid" to do it. You should use that word more carefully. Two people I respect told me specifically NOT to. I have taken their advice.
I have jumped lots of cars... usually people at work who don't carry cables ask me to because they know I do.

 

[StratTuner]

Did you understand anything in this thread? You don't need a new battery. Try buying a $40 1.25 or 2 amp charger and trick it into seeing your battery. You can always use the charger again in the future. Or spend three times that for unneeded battery? Makes no sense.

After two hours, I note that the charger I have (not the one you would like me to have) is not charging the battery in any way I can measure.
If I left it on for a week, I can deduce that it wouldn't charge this battery sice it made NO progress over a two hour period. I could be wrong about that.
My best guess is that the battery won't accept a charge. If that's true, then it's not wrong to think that it's time for a new one. Didn't someone say that draining a battery completely can damage it? Is that not so? Did that happen in this case? I have measurable evidence that it did.

I have a charger, thank you. I even linked to it. I'm sorry you don't like the charger I have.
To answer your question, No, I did not understand many of the things in the posts.
I'm sorry I'm not as smart as you are. Do you need to rub it in?