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A thought on battery tenders..........

B

BUBBAZANETTI

Guest
so as some of you know, i'm a rounder, so i have to get out on my bike periodically in the winter, but as i have no garage, i keep my bike at my parents house. i rode it today for the first time in 4 weeks and i couldn't get it started, the battery was amazingly dead, i had to put it on the tender for an hour to get it started....................

my question is this,

my bike stays in a tool shed, the shed is about 40 feet from the garage, i have a 50 foot extension cord leading from the garage to the shed where the tender and the bike are. my dad plugs the bike in for me once a week (in the garage), for about 8 hours while he's at work, then unplugs it when he gets home (what a swell guy :thumb ) anyway, he said he plugged it in last monday (but not today). i'm wondering if the tender, combined with the 50 foot cord is acting as a huge drain on the battery when unplugged in the garage. i would think that a battery, charged 7 days ago for 8+ hours would have plenty of charge, but for some reason, it didn't............

any thoughts????
 
The circuitry in any good battery charger should prevent an electrical drain from the battery to the power cord regardless of length. The diodes inside should prevent that from happening. Maybe take a voltmeter and see if you can measure anything acroos the prongs of the power cord??? :lurk
Just my 0.02 cts
 
Don't Unplug Tender

Leave tender plugged in at all times. It will draw current only as needed. Cost of electricity will be much less than a new battery due to deep cycling of discharge and charge cycles.
 
Last edited:
riderR1150GSAdv said:
The circuitry in any good battery charger should prevent an electrical drain from the battery to the power cord regardless of length. The diodes inside should prevent that from happening. Maybe take a voltmeter and see if you can measure anything acroos the prongs of the power cord??? :lurk
Just my 0.02 cts


this is what i figured as well, i'll test it when i get a chance


i've also heard conflicting veiwpoints on leaving the Battery Tender JR plugged in all the time with a Gel battey, good for maintence, but might cause problems with the Gels cause of varying cut off voltage.............
 
Most gel batteries charge well at 14.4 volts as the upper limit. When these batteries came out, chargers, both 110 V and on board vehicles, had to be changed to limit the output to this voltage. The new trickle chargers should be safe to leave plugged in and left on the charge mode for quite a while.They put out right around one amp or so of juice. Usually enough to keep up with the naturally occurring battery drain and a board computer/radio memory if so equipped. Low temps will cause a drain on a battery regardless of the bike it is in. IMHO you can leave the tender plugged in and buy your dad a nice bottle of whine or so for taking care..... :bottle :buds :laugh
 
BubbaZanetti said:
... i rode it today for the first time in 4 weeks and i couldn't get it started, the battery was amazingly dead, i had to put it on the tender for an hour to get it started....................

my question is this,

...my dad plugs the bike in for me once a week (in the garage), for about 8 hours while he's at work, then unplugs it when he gets home (what a swell guy :thumb ) anyway, he said he plugged it in last monday (but not today). i'm wondering if the tender, combined with the 50 foot cord is acting as a huge drain on the battery when unplugged in the garage. i would think that a battery, charged 7 days ago for 8+ hours would have plenty of charge, but for some reason, it didn't............

any thoughts????


Bubba:

My first thought is that it MIGHT be time for battery replacement. It sounds to me like it is not holding charge for very long (i.e. it appears to work immediately after removing the charger, but, a week later - nada). One of the nice things about GEL batteries is the low self-discharge characteristic. Check this out:

http://www.exide-automotive.de/en/produkte/gel/index.html

Meaning that you probably don't need a tender at all. At least according to Exide. And cold temperatures actually slow the self-discharge even further.

Second thought is that you have a malfunction inside your tender that is causing a back-drain. Normally, it should not matter if you leave the tender connected whether it is plugged in, or not. However an internal failure could conceivably turn the tender into a load that will discharge the battery. Related thought 2A, you have an abnormally high parasitic drain somewhere in the bike's electrical system. Either of these can be tested with an ammeter... got one?
 
soffiler said:
Bubba:

My first thought is that it MIGHT be time for battery replacement. It sounds to me like it is not holding charge for very long (i.e. it appears to work immediately after removing the charger, but, a week later - nada). One of the nice things about GEL batteries is the low self-discharge characteristic. Check this out:

http://www.exide-automotive.de/en/produkte/gel/index.html

Meaning that you probably don't need a tender at all. At least according to Exide. And cold temperatures actually slow the self-discharge even further.

Second thought is that you have a malfunction inside your tender that is causing a back-drain. Normally, it should not matter if you leave the tender connected whether it is plugged in, or not. However an internal failure could conceivably turn the tender into a load that will discharge the battery. Related thought 2A, you have an abnormally high parasitic drain somewhere in the bike's electrical system. Either of these can be tested with an ammeter... got one?

There were some early Exide GEL batteries made in '03 which would not hold a charge. Might be time as you say for a new battery. Glad you pointed out that heat causes drain, not cold. Chemical reaction rates double every 10 deg C.
Use the BT Jr. and also check out the bike off drain if possible.
 
Battery Tender

BubbaZanetti,

Leave the tender on all the time. I have my battery tender plugged in since November. Unplugged it for 1/2 hour to run the bike to circulate the oil within the engine and get rid of any condensation. After that I put it back, and it's been there since Mid January, and I'll unplug it again in first week of April and stay unplugged for most of the summer.

When certain amount of battery goes down, it will start the charge. When full, it fill stop charging the battery till at the point where it finds that it has gone below certain amount, and start charging it again.

I'd say leave the battery tender plugged on till you are ready to take it for a spin.
 
soffiler said:
Second thought is that you have a malfunction inside your tender that is causing a back-drain. Normally, it should not matter if you leave the tender connected whether it is plugged in, or not. However an internal failure could conceivably turn the tender into a load that will discharge the battery. Related thought 2A, you have an abnormally high parasitic drain somewhere in the bike's electrical system. Either of these can be tested with an ammeter... got one?



this is what i'm starting to think. i kept my bike at my place last night, started up fine this moring but i got the soild red abs indicators that wouldn't shut off (sure sign of a slightly discharged battery) after 22 miles i pulled over for gas and sure enough after starting, the ABS returned to normal operation. i can't remember if the stamp on my Gel said 03 or 04, i might just put the panasonic battery thats been on the shelf for a year in to see what happens.................
 
PAULBACH said:
Cost of electricity will be much less than a new battery due to deep cycling of discharge and charge cycles.

'specially since dad'll pay for the electricity, but probably not for the new battery :)

FWIW, my bike sits outside all the time, and sometimes I don't use it for up to 2 weeks. I've only had to jumpstart it once, but that was last winter. I think I flooded the engine back then :(. Normally it starts just fine down to temps in the twenties (didn't try @ lower than that). So it sounds like you might be having a battery issue...
 
Another variant

If you are worried about leaving the battery tender plugged in all the time hook it up via a light timer and have it go on a couple of hours out of every 24.
 
Leave Tender Attached

Went to recent BMW workshop for care and feeding of new motorcycles. Learned there is not left that shade tree mechanics can do. However we learned that with all the electronics on new motorcycles it takes the charging system at least half an hour to replace the amps it took to start the bike.

The advice of the tech was to always reattach the BT to keep battery at peak. The battery tenders are designed to be left in place - they are tenders not chargers. They also charge but take longer to do that job. Just bring the pigtail that came with the BT to the outside world and leave BT attached - except when you ride of course.

Good luck.
 
BubbaZanetti:

here is my food for thought... :eat

1. You should move somewhere so that you can ride 12 months out of the year. Money is not everything.... How can you live not looking at your bike daily??
2. Since you don't want to move, I take it, we have to deal with your situation: I would keep the battery tender on 24/7. The long extension cord will only lose power minimally. (Okay, I am not an electrician, but that is what I was told).
3. Replace the battery every 3 years regardless of performance and make sure that you service it at least twice per year.
4. Get a maintenance free dry cell battery instead of the acid type battery.

Go for a ride, it makes you feel better. :wave
 
Grumpole said:
If you are worried about leaving the battery tender plugged in all the time hook it up via a light timer and have it go on a couple of hours out of every 24.

Although they are "tenders", if you read the instructions that came with them they will say that you have to check the fluid level in the battery over the winter (tender time). That says to me that they can slightly overcharge. Since I don't want that to happen at all, especially on a GEL or AGM sealed battery, I turn on the charger every week or so and turn it off when it goes green. A GEL or AGM will stay charged for months, except for the clock, etc. so I think a week is a good interval. You can buy a 7 day timer, but I just remember to do it when I walk thru the garage.
 
Battery Tenders. Are they a throw-away item?

I bought a Deltran Battery Tender in 1999 when it was the only model. Later, I bought a Plus model, put the Plus onto my Roadster and moved the original to my restored '63 Buick Riviera. The Riv is sorely neglected due to motorcycle fun, but today I went to where it sits and the Battery Tender's red light was on - steady. Connections were good. I unpugged it, found that the battery was charged, and started the car (after the dry carb was filled by the mechanical fuel pump). No problem there.

After I chewed up the water pump shaft and bearing and made arrangements for that, I turned my attention to the Battery Tender. I plugged it in, and no light at all. I touched the clips to see if there was any 12v juice - nothing. Is the Battery Tender destined for the landfill? Do they wear out? I can pick up a BT Plus from M/C Accy Warehouse through Amazon for $34, so that's what I will do unless there is an easy fix.

TIA for any advice.

Fred
'02 R1150R
'63 Riv w/ Wildcat 445 engine that demands Sunoco 94 and LOTS of it! :rolleyes
 
FredRydr said:
I bought a Deltran Battery Tender in 1999 when it was the only model. Later, I bought a Plus model, put the Plus onto my Roadster and moved the original to my restored '63 Buick Riviera. The Riv is sorely neglected due to motorcycle fun, but today I went to where it sits and the Battery Tender's red light was on - steady. Connections were good. I unpugged it, found that the battery was charged, and started the car (after the dry carb was filled by the mechanical fuel pump). No problem there.

After I chewed up the water pump shaft and bearing and made arrangements for that, I turned my attention to the Battery Tender. I plugged it in, and no light at all. I touched the clips to see if there was any 12v juice - nothing. Is the Battery Tender destined for the landfill? Do they wear out? I can pick up a BT Plus from M/C Accy Warehouse through Amazon for $34, so that's what I will do unless there is an easy fix.

TIA for any advice.

Fred
'02 R1150R
'63 Riv w/ Wildcat 445 engine that demands Sunoco 94 and LOTS of it! :rolleyes

The "Battery Tender" has to be attached to a battery that is not totally discharged...like it has to see maybe 9 or 10 volts or something before it turns on. You won't see any sparks, etc by touching the leads together.
It's probably fine.
 
IMHO, trying to read a voltage across the input plug wouldn't work, as the internal transformer only works on AC, not DC.
 
I have a battery tender plus, and have at times left it unplugged from the wall (needed the extension cord) whilst connected at the battery...no discharge after a week...the usual testing/charging sequence that Delrans do was the only thing noticeable.
 
PUDGYPAINTGUY said:
I have a battery tender plus, and have at times left it unplugged from the wall (needed the extension cord) whilst connected at the battery...no discharge after a week...the usual testing/charging sequence that Delrans do was the only thing noticeable.

The BT has a diode in the output to prevent any current from flowing back into it.
 
In doing the math ...

In doing the math a new motorcyle battery is around $80 for the basic non space age lead acid variety. EBay does yield some bargains.

YUASA 12V 5-STAGE AUTOMATIC BATTERY TENDER can be had for about $40 on eBay.

The BT will extend the life of the battery. After removing the helmet and gloves plugging in the BT is the first thing I do when the ride is back home. Keep the electrical system happy and healthy or always carry a set of those nifty small battery cables.

Invest in a Battery Tender. The battery will always be at full charge and the entire electrical system will be at peace.
:thumb
 
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