Un- plugged Trickle Charger killed my battery !

Steve01 · Oct 29, 2015

Put a new battery on the bike just over a year ago (Lucas) no problems what so ever with it. In order to get the same sort of life out of it like the original one (7 years) I put it regularly every couple of weeks on trickle charge for a few hours to boost it back to 100%. Anyway to cut a long story short last week I did the same routine, waited for the charger turn to green then switched it off and un-plugged it from the mains. This time I left the charger connected to the battery via its fly leads. which I never normally do. I went back to the bike this morning hoping to take it for a ride and the bike was completely dead. Checked the voltage with my meter and it read 4.6 Volts. I have been trying to resurrect the battery all day with no luck (max 10v in the battery) so new battery had to be purchased. As this ever happened to anyone else ?

MrZappo · Oct 29, 2015

Not unless your charger is bad ... It should not do that if just left connected ...

For what you are doing, you really need a float charger as opposed to a trickle charger though ..

bluesdog · Oct 29, 2015

Lucas, The Prince of Darkness

900gc · Oct 30, 2015

Must.....restrain....from....Lucas....joke....Anyway, years back I replaced a battery (don't remember the brand) in another bike but it was crap from the getgo, wouldn't hold a charge for long and after a few months of keeping it alive constantly with a charger to use, it stopped holding enough voltage to work at all. My first (and only) experience with a new battery that was junk from the start.

Any warranty left on it to get some $$ back?

Steve01 · Oct 30, 2015

Update, apparently the trickle charger I have been using may produce excessive parasitic drain if left connected to the battery (Halfords make 1,25 amp charger). Anyway I have taken my bad battery back to the shop from which it was purchased, which they have tested and found it to be faulty, Full refund even though the battery was 14 months old and apparently only has a 12 month warranty, so a result from the supplier . Problem is the battery I have replaced it with is another Lucas recommended by the bike shop. Hopefully this will last a little longer than the last one

Donal · Oct 30, 2015

Good outcome.... Recommend you invest in something like an Optimate 3 you don't need anything more expensive with can-bus compatibility etc.

mcatrophy · Oct 30, 2015

Steve01 said:
Update, apparently the trickle charger I have been using may produce excessive parasitic drain if left connected to the battery ...

My son had to stop riding for an extended period (broken bones and stuff, predicted three months off riding, turned into 18 months). Anyway, he put his charger on his bike's battery, plugged it into a timer so it would charge something like an hour once a week. Totally sh*gg*d what was a new battery.

We measured its drain on his replacement battery, it was something like 200mA. 12 AH, 0.2 A, nominally 60 hours to fully discharged, once a week, every week for months. No wonder it destroyed the battery.

SouthernCruizer · Oct 30, 2015

Ride more, charge less. That is all.

900gc · Oct 30, 2015

SouthernCruizer said:
Ride more, charge less. That is all.

So says someone from Louisiana as we head into winter.

900gc · Oct 30, 2015

Steve01 said:
Update, apparently the trickle charger I have been using may produce excessive parasitic drain if left connected to the battery (Halfords make 1,25 amp charger). Anyway I have taken my bad battery back to the shop from which it was purchased, which they have tested and found it to be faulty, Full refund even though the battery was 14 months old and apparently only has a 12 month warranty, so a result from the supplier . Problem is the battery I have replaced it with is another Lucas recommended by the bike shop. Hopefully this will last a little longer than the last one

Great that you got a full refund even after warranty, do they know something about Lucas batteries you don't?

Fly Bye · Oct 30, 2015

I have been using Deltran battery tenders for over 18 years. They have maintained batteries in my trucks, cars, motorcycles and even my lawn tractor.

I have never had any issues what so ever with this product even in extremely cold temperatures.

audiowize · Oct 30, 2015

If you're going to leave a charger connected to a battery, but not plugged into the wall, you need to add a series diode between the charger and the battery to keep the charger from draining the battery.

This is a reasonable assumption by the manufacturer that you will use your charger to charge a battery, not to sit on the battery and not be plugged in.

Steve01 · Oct 30, 2015

audiowize said:
If you're going to leave a charger connected to a battery, but not plugged into the wall, you need to add a series diode between the charger and the battery to keep the charger from draining the battery.
This is a reasonable assumption by the manufacturer that you will use your charger to charge a battery, not to sit on the battery and not be plugged in.

This was the first time that I left the charger connected to the battery and not pugged in, never crossed my mind at the time that it would discharge and kill the battery in just over a week

I suppose I need to ride more and park the bike less or buy a descent battery conditioner

Steve01 · Oct 30, 2015

900gc said:
Steve01 said:

Update, apparently the trickle charger I have been using may produce excessive parasitic drain if left connected to the battery (Halfords make 1,25 amp charger). Anyway I have taken my bad battery back to the shop from which it was purchased, which they have tested and found it to be faulty, Full refund even though the battery was 14 months old and apparently only has a 12 month warranty, so a result from the supplier . Problem is the battery I have replaced it with is another Lucas recommended by the bike shop. Hopefully this will last a little longer than the last one

Click to expand...

Great that you got a full refund even after warranty, do they know something about Lucas batteries you don't?

I only purchased the Lucas battery on the recommendation of my local bike shop ..... are Lucas batteries really that bad

RichDoyle · Oct 30, 2015

I think this depends on the charger. Deltran states that their maintenance chargers will NOT pull current from the battery when AC is unavailable. This may not be true of all chargers. And no, I haven't put the DT charger I have to this test.

audiowize · Oct 31, 2015

RichDoyle said:
I think this depends on the charger. Deltran states that their maintenance chargers will NOT pull current from the battery when AC is unavailable. This may not be true of all chargers. And no, I haven't put the DT charger I have to this test.

They were nice enough to put the diode in there for you

I only mention this because I just put out a battery based power supply at work recently, and had to add the diode in poking up off the charger PC board to keep this very problem from happening.

Old Guy · Oct 31, 2015

I've got a car battery in my shop that's on a Battery Tender that's off most of the time. While I'm out there I'll turn the power strip on that it's plugged into, and the green light comes on within minutes. It appears it's not drawing it down.

jmgrif · Oct 31, 2015

Steve, not to offend, after all we have Newfoundland over here! When I was a wee guy growing up over here on the other side,imported vehicles from the UK came with the dreaded Lucas electrics. Word was when it rained the cars wouldn't start? Just trying to be funny at someone else's expense.

beemerdons · Oct 31, 2015

bluesdog said:
Lucas, The Prince of Darkness

+10 for Deltran Battery Chargers, -100 for any product with the word Lucas on it! First three motos were Brit Iron: Norton Atlas 750, Triumph 500 Speed Twin and a BSA 441 Victor Special. The weak link on all three machines were Lucas Electrics, you can ride a bike leaking oil but you can't ride a motorcycle with dead electrics! JSNS, Blimey and Bollocks!

NOTE: BMW Autos und Motoradden contracts all of their Chargers to be made by Deltran here in Estados Unidos! Der Krauts trust in Deltran, Jawohl Arnie!

Un- plugged Trickle Charger killed my battery !

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