Question on charging motorcycle battery...safe?

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Originally Posted By: Chris B.
I'm going to take the battery out and charge it out of the bike. How long should I charge it before unpluging the charger?


You can find a chart online that shows sitting voltage and its indication of state-of-charge at a given temp. You need a digital voltmeter as 1/10s of a volt count.

If you find yourself half discharged and you have a 16 amp hour battery, and a 1/2 amp charger, give it 16 hours. It'll slow down near full charge and for me that's good enough... no need to boil electrolyte etc. Of course the "smart" chargers can be left on longer but I like to save electricity... any transformer plugged into the AC uses a little power even if it isn't outputting any.
 
Originally Posted By: PT1
Originally Posted By: 47HO


BTW, HD does not make battery chargers; it is a relabeled Deltran "Battery Tender".


Uh no kidding........
smirk2.gif
They only assemble motorcycles. I just like the idea of the self shut off. I had a friend toast his battery, ecm & several relays by hooking up a POS battery tender to his bike and then forgetting to shut it off. So, I will pay the extra few bucks to get a decent one. But that's just me. Plus with the HD tender you don't have to take the battery out of the bike as it comes with a pigtail that stays on the bike. So you just plug it in. That is the point of buying the HD brand. If you know anything about Harley's they specifically tell you to remove the maxi fuse before you touch the battery. If you have the HD charger you don't have to go through that procedure. Way easier.


I think you missed the point of the quote from my post. The HD Tender IS the relabeled Deltran Battery Tender, the most popular "smart charger" on the market.
 
Originally Posted By: PT1
Originally Posted By: 47HO

Chris,

Your dealership spokesman is an idiot. He just wants to sell you something.



Oh yeah??? If you toast your ECM with that thing get ready to shell out a few hundred $$ for a new one plus a re-map if you have an EFI bike. You will need to remove your maxi-fuse every time you connect that thing or risk shorting out your electronics. Your dealer is telling you the truth.


YEAH.
 
The Harbor Freight pictured is a tender, you can leave it plugged in indefinitely with no worry of over charging or boiling the fluid. It's not just a simple trickle charger.
 
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Originally Posted By: 47HO
Originally Posted By: PT1
Originally Posted By: 47HO

Chris,

Your dealership spokesman is an idiot. He just wants to sell you something.



Oh yeah??? If you toast your ECM with that thing get ready to shell out a few hundred $$ for a new one plus a re-map if you have an EFI bike. You will need to remove your maxi-fuse every time you connect that thing or risk shorting out your electronics. Your dealer is telling you the truth.


YEAH.



LOL....OH YEAH!!!!!!
mad.gif
grin2.gif
grin2.gif
J/K
 
Originally Posted By: 47HO
Originally Posted By: PT1
Originally Posted By: 47HO


BTW, HD does not make battery chargers; it is a relabeled Deltran "Battery Tender".


Uh no kidding........
smirk2.gif
They only assemble motorcycles. I just like the idea of the self shut off. I had a friend toast his battery, ecm & several relays by hooking up a POS battery tender to his bike and then forgetting to shut it off. So, I will pay the extra few bucks to get a decent one. But that's just me. Plus with the HD tender you don't have to take the battery out of the bike as it comes with a pigtail that stays on the bike. So you just plug it in. That is the point of buying the HD brand. If you know anything about Harley's they specifically tell you to remove the maxi fuse before you touch the battery. If you have the HD charger you don't have to go through that procedure. Way easier.


I think you missed the point of the quote from my post. The HD Tender IS the relabeled Deltran Battery Tender, the most popular "smart charger" on the market.


Sorry, I bought mine from Zanotti's HD on line. I think it was $35. Just way too easy to easy with the battery pigtail that stays on the bike.
 
Originally Posted By: Redline955
I've been using the Battery Tender Plus for years. I used to take my battery out of the bike, but now leave it plugged in. The best charger, IMO. I have an AGM battery. We had a wicked lightning storm last summer, and it killed my battery tender. But even though it was hooked up to the bike my electrical system wasn't damaged. Got a replacement from Chapperal for 32 bucks.


You are lucky...better by some lotto tickets...
 
I'm still trying to figure how any battery charger could hurt the pcm. I'm sure no battery charger will raise battery voltage to more that 13.5v which is less than the charge system on the bike so how's this damage the pcm? Not doubting exactly, just wondering.
 
Originally Posted By: RonH
I'm still trying to figure how any battery charger could hurt the pcm. I'm sure no battery charger will raise battery voltage to more that 13.5v which is less than the charge system on the bike so how's this damage the pcm? Not doubting exactly, just wondering.


I had a friend who used one of those cheap ones and left it on the bike for several weeks. Burned out half of his fuses, battery, relays, and ecm on his Harley. Shouldn't have but did. Apparently it was putting out way more voltage than it should have OR he got a big power surge at his home and it was connected at the time. He was out of warranty and it cost him almost $700 to repair it. My guess it was a power surge but I still won't use a cheap charger anymore because of that. I also only plug into a surge protected outlet as well.
 
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I have one of those Harbor freight chargers and have used it on my Concours and my Cub Cadet.

I checked the output with my ammeter and in both cases the charge current was about 500 ma initially and tapered to under 10ma after 2 days. At that charge rate you could probably leave it on the battery indefinitely.

Provided there's not a problem with the charger, there's no reason to remove the battery from the bike while charging.
 
if you are concerned you can find the battery tenders on sale, i got the tender jr for around $20 or 30, really cant remember since it was so long ago. i leave it plugged in all winter, battery still in the bike and just use the pigtail that comes with it. Summer if not gonna ride it much i may leave it plugged in but most times dont.

I have never had a problem with any battery tender product
 
Here is a quick tutorial on battery charging.

Ambient charge of a 12v battery is around 12.75 volts (plus or minus a few tenths). When the batter goes bad (loss of a cell), you will see a drop in ambient voltage to below 11 volts. That is about 2.125 volts per cell (if you could measure them individually).
The charging circuit from the alternator will run the system up to about 14 volts. A really good charging system will run up to this voltage and then drop off to a float of about 13.2 volts- those are the high performance systems typically not found on autos or cycles. 14volts will work to recharge your batter and to run the lights and any heating units you have on board.

Smart chargers will try to run a charging pattern of a condition charge, absorption charge and a float charge. A true condition charge will go over 16volts - too much for electronics. Over the years this has been reduced to about 14.5 volts. This isn't quite enough to restore the battery, but it is safer for the attached equipment.

Absorption and float charges are reduced charges from the 14.5, but the float should end up at pretty close to 13.2 volts. You can keep a 12v battery at 13.2v for months at a time without losing too much liquid, without sulfiting the plates (or gas mat) and will be fully charged and ready to go.

I have used some commercial grade charges in the past with great success - have installed heavy duty alternators/regulators that have these same characteristics also with great success. But for a motorcycle, I have found the Battery Tender to work well for its intended use. I have even used it to charge a group 24 battery. My wife had to drive our vehicle 20 miles on the battery alone and it took about 24 hours to do it but it did - and even made it to the float stage. It comes with weather proof plugs so you can install them and leave it whereby battery charging becomes a plug-n-play affair. That is what I did on my Honda ST. I paid full price for it and for me it was worth it. If I wanted to do bulk charging, I would buy a cheap automotive battery charger, bring the voltage up to 14.5 (installed in vehicle) and 15.5 uninstalled, then disconnect it, let the voltage fall to 13v and connect the Battery Tender to it and let if float charge the larger battery. Kind of a "poor man's" commercial charger.

Hope this helps,

mike
 
I have been using a BatteryMinder from our local battery supply. They retail for $50, but he sold me 2 of them for 32 each. All I can say is that regular 1A and 1.5A battery chargers or trickle chargers can damage your battery. Either they maintain at too high continuous voltage, like 14 volts on up to 16 volts. Or, the cheaper chargers that shut off completely, and then turn back on will sulphate a battery in no time, rendering it trash. I've been through this with riding lawnmower, motorcycle and boat batteries. I will not use one of these chargers again, except for a few hours.

The better chargers will have 2 or 3 stage charging and are actually beneficial to your battery's life. In the case of the BatteryMinder, it wil charge at the 1 or 1.5A rate until the battery reaches 14.1 volts, then it will drop back to the maintaining voltage of 13.1 volts and at the same time apply pulsed current to the battery that is supposed to clean some of the lead sulphate crystals off the plates and keep the battery in service for a longer time. This is the "conditioning" pulse that some chargers have. I can leave this charger hooked up for years and the battery is ready to be used whenever.

Battery Tenders have a good reputation, too. I have also seen something similar at batterymart.com called Battery Defender chargers. They seem to be competitively priced as well, and includes a 3 stage conditioning, pulsed charge as well.
 
I use a 1 amp trickle charger by having quick connect pig tails that I made using two conductor trailer parts from Auto Zone. I ride year round but obviously in the winter I may go weeks without riding. I would never leave one of these hooked up all the time. I just put it on a few hours on each bike the night before when the weather looks like it will permit riding. Or if riding is not possible put two hours or so on for good measure every few weeks. Yes I charge the battery in the bike, thus the pig tails. No use removing the seat every time I want to give the battery a little boost. If you already bought it, use it.
 
The Battery Tender is what I use, and it has worked flawlessly for 8 years. I pull the batteries from both scooters, and the travel trailer. I alternate the charger weekly between the three batteries, 1 week on, two weeks off swapping when I move trash from garage to street on Thursday nights. The wall wart charger mentioned will work also, but I doubt it is a smart charger, shutting off when needed. I suggest a simple timer. Program the timer to run 12 hours once a week, hook it up, and forget the thing until spring. Probably not a bad idea to only charge with the battery disconnected if using an inexpensive charger: no telling what kind of filtering is in it for clean power without AC ripple. While the DC may be fine, I have observed AC ripple on the line from those chargers. Off topic, but that is how they used to get phones to ring.. phone lines were 48VDC, and they imposed 110AC on the line to get the clapper to vibrate against the bell.
 
I have bought and tried 2 of those little trickle chargers from Harbor Freight and they were junk, neither worked or changed the battery.

I have 3 Deltran Battery Tender Jr. I use the quick connects and use them on my motorcycles and ATV's. They work great. I get 5-6 years out of an AGM battery.
I juste the Battery Tenders all winter and also anytime somthing sits idle for more than a month or two.

These little chargers will also completely charge a dead battery and then maintain it. I like them cor cganring because they dont "zap" a battery with too many amps.
 
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