Hi guys,iin the recent past i posted a few times here in hdorums that i had been tracking premature battery failures on bikes & on classic cars both of which have times on low use or when in off season storage & found with these premature battery failures (failed in approx 2yrs or less) that a maint / float charger was used in either 24/7 or very often in most cases of premature battery failure.

Thats why i dont leave a maint charger on my bike on my bike 24/7 and remove it soon after battery hits full charge and charger go's to float charge rate/mode to avoid overcharging which i suspect is why so many batteries using float chargers have failed prematurely.

With that said what i found that "quietly " backs up what i had already suspected is Deltran now mfgs float a charger with an automatic 72hr shut off feature .

And guess what,a Yuasa 1.5a maint/float charger i recently bought has the same 72 hr what they also call safety shut off feature too.

I think whats happening is the battery and or battery charger mfg's have known for a while that in some cases when using float/maint chargers 24/7 or often that they overcharge the battery damaging it causing them to fail prematurely which is why they added ("quietly" with no fanfair or advertising hype) to not have pay money if they were to admit their product was in fact casing premature battery failure is Deltan's what they call " 72HR SAFETY SHUTOFF " that i think is really there to avoid overcharging / damaging the battery like they already know has been happening for quite a few yrs now.

I tracked that issue for a few yrs including contacting hundreds of people that had premature battery failures to ask if they used a float/maint charger or not and most of the time the ans was yes 24/7 or very often.

Anyway,see below for what Deltran's sales ad description say showing it has the 72hr safety shutoff feature and then decide for yourself weather to use a flaot/maint charger 27/7 & or leave it on the battery for long period after hitting full charge neither of which i do or rec anyone do.

Scott

About Battery Tender Plus High Efficiency 022-0186G
The Battery Tender 5.0 amp Charger is a quality battery charger that helps maintain the health and stamina of any 12 volt battery. With an input of between 100v and 240v of AC power and an output of 12v of DC power, this charger will keep your batteries full and healthy while they are not in use. This charger uses four primary steps for battery charging: qualification, bulk, absorption and float, each assuring the quality upkeep of your 12 volt battery. The charger has a 72-hour safety timer, and it is spark proof, short circuit protected and reverse polarity protected. Plus, the Battery Tender 5.0 amp Charger is backed by a quality 5-year warranty.

 

I am guilty of this in the winter for sure. Good post.

 

It's a feature that shuts off charging the unit if the battery isn't accepting a charge.
http://www.batterytender.com/021-0134-man.pdf

 

Have had no issues whatsoever using a battery tender plugged in 24/7. oem batt lasted 7 years. Looks like the 72 hr safety switch activates when the battery has been plugged in for 72hrs and it never reaches full charge. I always charge a new battery fully before installing. I wonder how many of the "hundreds" of users did that?
Added:I have had my battery tender since 2008.

 

I also do the same on all my new batteries. Keep them on maintainer/desulfator 24/7/365 when not in use. 5 years is the shortest battery life to date. Not bad since I usually get the cheapest battery price wise I can find.

 

My original 2002 Sportster battery is still going strong; I always use the Deltran Battery Tender JR when in the garage. Yes I know it's a 14-yr-old battery and should be replaced

 

Scott you're misrepresenting what the Battery Tender 72 hour shut off is for and Hausguy posted a link you should read.

If the Battery Tender continues to put out a 5 amp charge, indicating the battery is bad, the unit will shut off after 72 hours. On a good battery the charger automatically switches from 5 amp to maintenance mode. If you don't understand how it works give them a call.

http://www.batterytender.com/

http://www.batterytender.com/Motorcy...fficiency.html

 

Interesting post. Good friend of mine put a Big Crank in his bike around the same time I did. He never puts it on a tender (I even gave him one as a gift), and I use it religiously. I was visiting him in AZ for the River Run and noticed a new Big Crank sitting in his garage. I asked, is you battery going bad? He said, "Yes actually, it turns the motor over, then there's a small pause before turning it over again". "Interesting" was my response, "mine is doing the same thing and been contemplating replacing mine!". My conclusion from that experience is, the same battery started acting up whether on a charger or not. I haven't decided what to do with that information for the time being.

 

I got 16 years on my 57 buick plugged in 24/7. I check the water level 4-5 times a year and add when needed. The charger for my 08 ultra hangs from garage door track . that is where i park it and always plugged in . battery original and bike has 50,000 miles no issues !

 

The NUMBER 1 cause of premature lead acid battery failure is in how you prepped and charged the battery BEFORE it was was ever installed in your vehicle. Any other comment is anecdotal. If you just bought a battery off the shelf, tossed it on the bike and started it up, then you've most likely destroyed its longevity. The most important thing you can do is to properly bring a brand new battery up to full charge before you ever pull current from it.
Most people believe that an off-the-shelf battery is bought ready to go, this is the furthest thing from the truth. You must slowly bring the new battery up to full charge with a charger rated at no more than 10 percent of the battery's rated current, ie; a 10 amp battery should be charged at no more than 1 amp, a 30 amp battery at 3 amps, etc. This should be done over a period of 10 hours or more before you ever install it. An off the shelf battery has a holding charge that will be strong enough to start your bike, but in doing so will irreversibly damage the battery's plates and chemical structure. This is guaranteed to shorten the battery's lifespan, and is in fact what most people do. Unless you know how the battery was conditioned before putting it into service, all the suppositions on trickle or float charging mean absolutely nothing.
A properly prepared battery will easily give you 5-7 years life out of it.