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Am I killing my batteries?

N

nickrides

Nick Kennedy
Gents
For those in the know of the finer points....
On my 1990 K 75 RT I know there is a light parasitic power draw when the key is off. I've been leaving a Battery Tender Jr, 750 ma., hooked up to it.
When it's hooked up the voltage reads 13.2 V. Is this Ok long term? When I fully charge the battery and disconnect the ground lead the battery settles down at 12.8 for about a month and then goes to 12.7.
I've noticed that when I disconnect my batteries for the winter lay up and charge them once a month they seem to last much longer.
On another bike, My 1978 R80/7I left this charger on for the winter and the battery, a flooded lead acid, ran dry and ruined it.
Then this spring on another bike I left this charger on, for the winter, a sealed lead acid battery and it failed at the 24 month point.
Am I killing my batteries by leaving them hooked up at 13.2V all winter?
When my K 75 RT is running, FWIW, the voltage is 14.1V which is normal I believe.
Thanks in advance!
Nick
 
All your readings sound good to me. The chargers are designed for maintenance/storage charging.
OM
 
Nick,
I wonder if there may be an issue with your charger? I have four BMWs all on floating chargers, albeit just inexpensive HF floating chargers, and always get four to six years. If they're not being ridden, they're plugged in. I simply use the BMW or Westco glassmat batteries. Nothing fancy or expensive, with no issues.

The lead acid battery you described sounds like it was over charged, like the maintenance charger didn't sense when the battery was at full charge and reduce or stop the charging. I'm not sure how to test your charger but since you've had issues with several batteries, you might try a different charger. Good luck with finding a solution soon. They don't give those batteries away! Take care and ride easy.
gp
 
Even though they are supposed to be okay on a charger full time (don't run them dry), I won't do that.
I charge my bikes about once a month, sometimes longer. I just run them on a smart charger (trickle) overnight, then remove the chargers. My AGM batteries on my Airheads usually last 5-6 years, then they are replaced just to be safe. My Oilhead has an AGM too. I'm a little over 3 years on this one. ABS voltage testing makes changing these out an earlier event. Probably replace this one in the Spring at 3 1/2 years.
 
Michael,
Respectfully, I'll continue to do this as it's worked fine and consistently for me for forty plus years.
gp
 
I have killed 4 batteries with the Deltran battery tender jr. I now use noco genius chargers once a month with great success. The first jr that failed killed a car battery over the winter. It stuck in full charge mode and boiled the battery dry.
 
beemerchuck said:
I have killed 4 batteries with the Deltran battery tender jr. I now use noco genius chargers once a month with great success. The first jr that failed killed a car battery over the winter. It stuck in full charge mode and boiled the battery dry.
Click to expand...

Full charge, the light is usually red. On the car battery- (really all of the batteries going to be “maintained”), they have to be in a state of being stable enough to be maintained.
BTW, I have no problem with the once a month....up to charge, method of maintaining charging.
OM
 
I have a Deltran battery tender and a cheap Harbor Freight tender and leave my motorcycle batteries hooked up all winter, never an issue. I usually change out batteries after 3-4 years because I just don't want to take the chance. I had a battery fail on my 1,500 miles from home. It would start the motorcycle fine, as long as it started the first hit, second try was a struggle. I found a Batteries Plus and swapped it out.
 
m_stock10506 said:
Even though they are supposed to be okay on a charger full time (don't run them dry), I won't do that.
I charge my bikes about once a month, sometimes longer. I just run them on a smart charger (trickle) overnight, then remove the chargers. My AGM batteries on my Airheads usually last 5-6 years, then they are replaced just to be safe. My Oilhead has an AGM too. I'm a little over 3 years on this one. ABS voltage testing makes changing these out an earlier event. Probably replace this one in the Spring at 3 1/2 years.
Click to expand...

i do the same thing. four bikes and a car. all with AGM batteries. one charger. rotate which one is being charged every few days. DIN plugs on all of them make it simple. batteries last many years.
 
m_stock10506 said:
Even though they are supposed to be okay on a charger full time (don't run them dry), I won't do that.
I charge my bikes about once a month, sometimes longer. I just run them on a smart charger (trickle) overnight, then remove the chargers. My AGM batteries on my Airheads usually last 5-6 years, then they are replaced just to be safe. My Oilhead has an AGM too. I'm a little over 3 years on this one. ABS voltage testing makes changing these out an earlier event. Probably replace this one in the Spring at 3 1/2 years.
Click to expand...

I use a similar procedure. Two chargers rotated between RT, minivan, compact tractor, and a CB175, none of which sees very much use these days. Charge for 4 to 24 hours every 3 to 4 weeks, depending on when I think about it. The Odyssey in the RT is nine years old, the tractor battery is six (the previous one lasted 10 years). They all start easily, though I do now carry my jump battery on the RT, "just to be safe".
 
Guenther
I haven't measured it but it has a electronic clock, so I know there has to be some very small draw for that.
That tender I use has 3 lights
Solid red is charging
Blinking red is almost fully charged
Green is charged and sits at 13.2 or .3 V
 
beemerchuck said:
I have killed 4 batteries with the Deltran battery tender jr. I now use noco genius chargers once a month with great success. The first jr that failed killed a car battery over the winter. It stuck in full charge mode and boiled the battery dry.
Click to expand...

Sorry for your bad luck... failed charger

I've been using Deltran Battery tenders for well over 10 years. I've got 6 of them connected now. Ranging is size from lawn mower to Diesel farm tractor (battery weighs over 50 lbs).
I do use different Deltran ratings/ for different size batteries. As long as I see the green "maintain mode" light I'm happy

ps before I used Deltran I had to change the heavy/expensive farm tractor in 4-5 years, I'm now on 7 years and it started up at 20F last week fine.

I'm sold on them
 
I too have had excellent results with Deltran chargers. I have 4 bikes on them now, and a dual bank charger handling an ATV and a welder/generator, etc. I have never had any issues, and just periodically check for the 'green light', as does vtbob. Batteries all typically last 5 years + or more.

Good luck,

ECJ
 
nickrides said:
Guenther
I haven't measured it but it has a electronic clock, so I know there has to be some very small draw for that.
That tender I use has 3 lights
Solid red is charging
Blinking red is almost fully charged
Green is charged and sits at 13.2 or .3 V
Click to expand...

Nick,

Are you sure it's not a blinking GREEN for almost fully charged, all mine are. Blinking red usually means something is wrong (like no battery connected, or a battery fault, but will not pickup all battery faults).

Just to be clear, a Battery Tender Jr. has ONE light with four modes, blinking red, solid red, blinking green, and solid green.




:dance:dance:dance
 
I have Battery tender Jr on five cars and 2 motorcycles, not any issues with over charging. I was first was using the HF float chargers, but when I checked the output of the units most were under 12 volts, many were under 10v volts so I threw them away and bought the Deltran units.

gg
 
I've been using Battery Tender Jr's. for 20+ years. During that time I've had one fail and due to the light configuration referred to earlier, I knew it. I plug my bikes in after every ride during the summer and leave them connected all winter. My experienced AGM battery life is over 6 years.

Not to derail the thread - my lithium battery is now 7 years old and continues to work well with minimal (30 minutes on the BT Jr. per month) maintenance.
 
Charger

I have 2 of the battery tender jr on one the light stays red and just keeps on charging never goes to green other one works correctly
 
179212 said:
I have 2 of the battery tender jr on one the light stays red and just keeps on charging never goes to green other one works correctly
Click to expand...

I would swap between batteries and see if your results change. A battery at the end of it’s service life can cause the battery to never be seen as “charged”, keeping the red light on.
OM
 
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