Battery tender question

[TTD]

So my dirtbike has been sitting for 2 months. I connect the battery tender and it goes green immediately? Surely the battery can't be fully charged after that time in unheated garage?

[DuncanMoto]

If it's a AGM battery it could be.

[Stoneman]

So my dirtbike has been sitting for 2 months. I connect the battery tender and it goes green immediately? Surely the battery can't be fully charged after that time in unheated garage?

If the battery was initially deep charged properly (and don't EVER let a retailer tell you it has), it was stored fully charged and there's not a drain on it, it sure can hold a charge. My wife's ATV has sat since LAST WINTER under the same conditions as your dirty bike, battery cables still attached. I slapped the trickle charger on it this past weeked and it showed fully charged. I disconnected it, turned it over, and in sub-zero temps, it fired right up!

[TTD]

Well, that would be cool if it holds that long. The previous owner set it up with a battery tender connection, so I didn't bother removing the battery (like I do with all my other bikes)

The other bike batteries are in my heated basement... and every couple of weeks I put the charger on them... and it starts off red.

Just seemed odd that the battery out in the cold would hold it's charge better?

[FirstDuc-1098]

I had a snowmobile battery do the same thing, when I tried to fire up the sled, it turned over a couple times and then the battery wouldn't crank it any more, I think a cell is shot so it shows it fully charged but really isn't, new battery started sled fine

[Doc]

Or your trickle charger is broken...

[TTD]

Or your trickle charger is broken...

works normally on my other batteries inside.

guess I'll have to wait until springtime to see if the dirtbike turns over properly.


thanks all... guess we wait and see now.

[mikeb]

mine does that sometimes. leave it on for awhile and see what happens. sometimes they seem to get a false signal. i have a battery tender jr.

[keeena]

Just seemed odd that the battery out in the cold would hold it's charge better?

Cold weather won't cause a battery to lose its charge faster than warm.

[Stoneman]

Cold weather won't cause a battery to lose its charge faster than warm.

It will if it's not fully charged. That is, a fully charged battery won't freeze...

[TTD]

If it's a AGM battery it could be.

Is this the "jelly" batteries?

I don't know what I have, to be honest. I think it's the stock battery (2007 KTM450exc) which is probably just a regular old sealed motorcycle battery?

[ZX-12R]

Is this the "jelly" batteries?

I don't know what I have, to be honest. I think it's the stock battery (2007 KTM450exc) which is probably just a regular old sealed motorcycle battery?

Jelled electrolyte batteries are different than AGM which stands for Absorbed Glass Mat. In an AGM, a type of fiberglass mesh sits between the lead plates in the battery and the electrolyte is suspended within it. The big advantage to them is they can't spill since the glass mat is only 95% saturated. They also have an extremely low self discharge rate that averages between 1-3% per month and are highly resistant to shock and vibration which makes them good choices for all types of recreational vehicles.

I have no idea what comes with your KTM but there is a pretty reasonable chance it's AGM since quite a few modern motorcycle batteries are set up this way.

[Pigman]

Mine is a Deltran and full green means it's 100% charged...

[Stoneman]

Let's not get overly complicated here. If it's fully charged and has never been discharged, it can sit in freezing weather without discharging. Like I said, my wife's ATV hasn't been ridden since Feb. 2010 and fired right up. Proper initial deep charge, never been discharged, didn't need any charging. And it started in the sub-zero temps we had last weekend...

[TTD]

Let's not get overly complicated here. If it's fully charged and has never been discharged, it can sit in freezing weather without discharging...

I hear ya, Jay.

It's just in all my years, this is the first battery doing this.

Even on a really good batter... I would expect maybe the battery tender to go red for a bit (even if it's just 5 minutes) - then go green.

Like I said, even the batteries that are fully charged and sitting in my heated basement do this after a few weeks.

I fear that something is different because this battery is in the bike and attached to all the electrics?

[Stoneman]

I hear ya, Jay.

It's just in all my years, this is the first battery doing this.

Even on a really good batter... I would expect maybe the battery tender to go red for a bit (even if it's just 5 minutes) - then go green.

Like I said, even the batteries that are fully charged and sitting in my heated basement do this after a few weeks.

I fear that something is different because this battery is in the bike and attached to all the electrics?

Exact same scenario with Big Shirl's ATV, EXACT...

[TTD]

Exact same scenario with Big Shirl's ATV, EXACT...

Sounds good... hopefully it fires right up come spring.

[Stoneman]

Sounds good... hopefully it fires right up come spring.

You could fire it up right now and remove all doubt...

[xsiliconkid]

turn on something electrical on the bike like a headlight, this should immedialtely make the charger drop showing full charge... if not the battery is NBG

[TTD]

You could fire it up right now and remove all doubt...

It is all winterized... don't want to put gas back into carbs.

[Stoneman]

It is all winterized... don't want to put gas back into carbs.

Hear that noise going over your head?

[TTD]

Hear that noise going over your head?

Yes.. it is my plane coming to pick me up and get me the hell outta here.