Flat dead battery

[BwanaDik]

It's 2 1/2 years old, bought it 8/09. I've always kept it charged, zero electrical issues. However, I apparently left my GPS or something else on because I came out at lunch today to ride it back to work (nice day!) and had ZERO juice. I left the key on for a few minutes and heard a pathetic buzzing from under the tank. Probably the fuel pump making an effort.

So it's on the charger now, pulling like one amp, if that. 12.4 volts seems to be as much as it will do on the charger. Had it on there for about 45 minutes.

So the question? Is it shot? Will it recover if I leave it on the charger for a few hours? Have I damaged it to some extent that the life will now be less that "normal"? Any guesstimate as to how long it should sit on the charger until I know it's either bad or recoverable? I'd like to ride tomorrow morning but still have time today to get a battery if necessary

Or should I bail on the side of reliability and just get a new one?

It's OEM Yamaha

 

[TomInPA]

It will take several hours to bring that battery back to full charge. If you have access to a 2-amp charger I would use that. Since it hasn't been discharged for long, it may not have sulfated too much, but there are chargers can can reverse some sulfation. I would look for a good 12.9 volts from a fully charged battery. Most can reach over 13 volts, but may not stabilize there.

I feel you pain. I have a GPS on battery power, and forgetting to turn in off will take out the battery pretty fast.

 

[BwanaDik]

It will take several hours to bring that battery back to full charge. If you have access to a 2-amp charger I would use that. Since it hasn't been discharged for long, it may not have sulfated too much, but there are chargers can can reverse some sulfation. I would look for a good 12.9 volts from a fully charged battery. Most can reach over 13 volts, but may not stabilize there.

I feel you pain. I have a GPS on battery power, and forgetting to turn in off will take out the battery pretty fast.

Thanks Tom. I've left it on while back to work, I'll check this afternoon. I'm using a quality charger with the 2/10/start selection (can't remember the name right now) and I think it will go all the way to 13.4 VDC

 

[blrfjr]

As long as it hasnt set all winer long at zero it should come back. I think you will be fine.

 

[rickysnickers]

I might suggest one of these, https://www.bikeeffects.com/proddetail.asp?prod=LS12%2F0.6&cat=8595

Rick

 

[SkooterG]

Thanks Tom. I've left it on while back to work, I'll check this afternoon. I'm using a quality charger with the 2/10/start selection (can't remember the name right now) and I think it will go all the way to 13.4 VDC

I don't think that was a good idea. Those chargers are for bigger car batteries, not motorcycle batteries. Hope you don't cook it while you are gone.

I would say your battery has suffered permanent damage. Whether it's enough to need to be replaced remains to be seen.

 

[joebiodiesel]

You're not going to know for sure until you give it a try. I'd recharge it and let it sit for 24 hours without being connected to anything. If it maintains 12.6 or 12.7 volts then put it back in the bike. If it's anything less than that I'd can it.

While this is far from a perfect battery test, it should work for your purposes.

Joe

 

[BwanaDik]

Update: It's dead. Had it on the charger for about 8 hours and it nevr got above 13.2 on the charger, 12.4 off the charger. It would run the fuel pump but not turn the starter.

Sigh....New battery on the install list for this morning

I know we've got a lot of battery threads around here but I've not seen a clear explaination of why this happens (I looked but may have missed it). For example, say you have a bike with carbs (remember those?) so you don't need power for fuel. Your bike won't start and you run the battery down to zero trying to turn it over. Flat. ead. Nada. Zip power left. We've all done this sometime in the dim past. You put it on the charger and a few hours later it's OK.

Then you have a situation like mine where the battery is drained slowly over many hours. Now the battery won't recover.

What's the difference?

 

[mcatrophy]

Update: It's dead. Had it on the charger for about 8 hours and it nevr got above 13.2 on the charger, 12.4 off the charger. It would run the fuel pump but not turn the starter.

Sigh....New battery on the install list for this morning

I know we've got a lot of battery threads around here but I've not seen a clear explaination of why this happens (I looked but may have missed it). For example, say you have a bike with carbs (remember those?) so you don't need power for fuel. Your bike won't start and you run the battery down to zero trying to turn it over. Flat. ead. Nada. Zip power left. We've all done this sometime in the dim past. You put it on the charger and a few hours later it's OK.

Then you have a situation like mine where the battery is drained slowly over many hours. Now the battery won't recover.

What's the difference?

The difference is the deep discharge when you leave it on load for an extended time. It goes beyond "flat" to "pear-shaped".

[edit] Perhaps slightly more helpfully, when you've been trying to start the bike and it gets to the point where it won't turn the starter motor, it is fully discharged. Other than that it has suffered no significant damage. However, you can still draw a lower current from it, it will still light a bulb albeit dimly. In this state you are starting to pull chemicals off the plates.

This has several effects

• If you do charge it, the active area of chemicals is reduced, it is of lower capacity, and reduced maximum current draw available so it won't turn a starter motor.
• Another is that the stuff pulled off the plates sits in the electrolyte between the plates allowing current to flow between them, so continuously discharging the battery. In this case the battery won't hold a charge.
• Another effect is where, as it is deep discharged, it can build up a relatively non-conducting layer on the plates. Now it is difficult to charge the battery with a normal battery charger. There are some chargers that will recognise this state and apply a higher than normal voltage in order to try to punch through this non-conducting layer.

[/edit

 

[Donal]

There are two things which are detrimental to AGM type batteries -

Deep discharging (below 50% capacity).

Over charging in an attempt to recover.

Sounds to me like you scored a perfect two out of two

Don

 

[RossKean]

Went out to go for a short ride today. WTF - the windshield is still up??? Key was left on for 24 hours. This is on a 2007 with the OEM battery. Boosted it and ran the engine for 10 minutes or so. Decided to put it on a slow charge . It appears to have taken the charge OK and it starts the engine with some authority. May have dodged a bullet on this one although I will reserve judgement until I find out whether it will start after sitting overnight.

Ross

 

[RossKean]

Went out to go for a short ride today. WTF - the windshield is still up??? Key was left on for 24 hours. This is on a 2007 with the OEM battery. Boosted it and ran the engine for 10 minutes or so. Decided to put it on a slow charge . It appears to have taken the charge OK and it starts the engine with some authority. May have dodged a bullet on this one although I will reserve judgement until I find out whether it will start after sitting overnight.

Ross

So far, so good. Went out and started the bike this morning and it went without any hesitation! This is the second time I have done this in the two years and 50,000 miles I have owned the bike and I seem to have gotten away with it. AGM batts do NOT like to be run to the point of complete discharge. I hope to be able to get at least this season out of it.

Ross

 

[BwanaDik]

Yes, I believe you did dodge a bullet. Update on mine: I installed a new one (first charged it on the bench) and all is now good! It turned over with vigor, much faster than with the old battery. Strange, 2 1/2 YO should be OK. The voltage was always above 13.5 too.

I don't think using a full sized Dayton charger on a M/C battery is detrimental if you're smart enough to set the switches to the right settings (I hope I am)

 

[RossKean]

I don't think using a full sized Dayton charger on a M/C battery is detrimental if you're smart enough to set the switches to the right settings (I hope I am)

A "full sized" charger will be OK if you can set the charge rate to NO MORE than about 2 amps. Higher than that and you will cook the battery.

 

[Powerman]

I think car chargers are a bad idea for MC batteries, too easy to cook the cells. A MC charger is cheap, and a maint mode model with high frequency is great for desulphating.

I have two very little used vehicles and need to keep on top of things. Last week I needed to use my truck to haul my welder, of course it was dead.

I've been meaning to charge it, but blew it off. The spare battery I charged in the garage was of course 1/2 inch too wide. I put the original on overnight on the car charger and it didn't work, I never could the cells up to voltage. I used the MC charger on High Freq overnight and it worked perfect.

It's a fine line when they get close to flat. Note to self: install the Datel on the FJR.