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Battery tender

BRUCETONER

Bruce Toner
Should a battery tender charge my BMW battery fully when pluged in though one of the two auxilary jack on the LH side of my 2002 rt? It is either not charging fully or the battery is compromissed. The battery charge seems to deplete quicker than I think it should. With the bike running I am getting 14 volts when checked at the battery. I need to buy the necessary epuipment to do a load check on the battery. Any other ideas?


Cheers!

Bruce
 
There is a great product out there called the Argus Battery Bug, it will tell you more about your battery than you ever wanted to know. The Cliff's Notes version is that it will constantly monitor the health of your battery and let you know well in advance if it is failing. Here is a good YouTube vid on it:
http://www.youtube.com/watch?v=Ayya5kOMmyY

Well worth the $35. They make them for cars and boats as well as motorcycles so make sure to get the Moto one.
 
Should a battery tender charge my BMW battery fully when pluged in though one of the two auxilary jack on the LH side of my 2002 rt? It is either not charging fully or the battery is compromissed. The battery charge seems to deplete quicker than I think it should. With the bike running I am getting 14 volts when checked at the battery. I need to buy the necessary epuipment to do a load check on the battery. Any other ideas?


Cheers!

Bruce

Are you sure that the aux jack goes directly to the battery? With the canbus system it may not be. With the ignition off check the voltage at the jack and see if it's hot. My RT has one that is hot and one that is wired through the canbus and it is not. So the tender won't reach the battery in that one.
 
Hey Ted... thanks for the info. I just watched the video on the battery bug. What an awsome tool for the price. Will definately be installing one of those. I purchase a battery load tester today to check my battery. With a load it is dropping to about 8.5 volts. I guess that's the issue. I installed that OEM BMW battery only 2 years ago. The bike is stored in a heated garage all winter and I put the battery tender on it a couple of times during the winter season to ensure it remains fully charged. A lot of money for poor battery life.

I ordered a Lithium Ion battery today from Shorai. A little on the pricey side but if it is as good as they say it is it will be worth it. Nothing more frustrating than being in the middle of a 5 day loop in the company of several Japanese bikes and a Harley or two and we're bump starting the BMW? Definately no material there for a BMW commercial.
 
The bike is stored in a heated garage all winter and I put the battery tender on it a couple of times during the winter season to ensure it remains fully charged.


IF it is indeed a Deltran Battery Tender or Battery Tender Jr., the ideal situation would be to leave it hooked up all through the non-riding season. Battery Tenders go into a Float Mode once the battery is fully charged. It doesn't charge enough to dry out the battery, but it "stirs" it enough to prevent sulfation (the leading cause of sitting batteries to loose capacity). It WILL greatly extend the life of your batteries.

The battery in my trailer was purchased in 1994 and is still going strong. It still passes a load test with flying colors. The battery in my wife's 635 is 11 years old. She only drives it once or twice a month so it lives on a Battery Tender Jr. I have a couple other batteries, that don't get used, on BT Jrs and they are always ready to go. Letting a battery sit in a partially discharged state is not good for it. Any battery that sits for long periods should be KEPT on a tender when not in use.

The Jrs. are cheap. If you search the net, you can find them for less than $25 ea. A LOT cheaper than batteries!


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Argus Battery Bug is no longer. The company closed down October 2012. That is why it has been so hard to find!


Bruce
 
Should a battery tender charge my BMW battery fully when pluged in though one of the two auxilary jack on the LH side of my 2002 rt? It is either not charging fully or the battery is compromissed.


Cheers!

Bruce

What color is the light on the Battery Tender? If it's red or flashing green, it's not done charging.


I doubt that the lithium ion battery is compatible with your battery tender. I believe that they take special chargers.

Update: I checked Shorai site, and IF your battery tender is made by Deltran, it will work and you don't need to use it usually:

Q. Should I use a battery tender?
A.The short answer is "only if you really need to". Most powersports enthusiasts have gotten used to hooking up a tender to their lead-acid batteries, all the time. Shorai LFX have much slower self-discharge than the best lead acid do (1/6 to 1/7, on average), they do not sulfate as capacity drops, and they are the ultimate "deep cycle" battery, which means that they can still crank your vehicle even if the remaining capacity is quite low. Therefore most riders will not need to use a tender at all. Even a charger or tender uses energy you have to pay for, and there is always the possibility that a charger or tender can fail in some way, so if not really needed the best practice is to not use one.
A fully charged LFX can sit for a year or more and still retain adequate starting capacity, without damaging the battery. As such, any vehicle which has no current flowing when the key is OFF should never need a tender. At most it should be charged every 6 to 12 months, depending on the average storage temperature (cool storage is much better for any battery). Many older vehicles and most dirtbike/atv fall into this category.
Newer vehicles may have a significant draw even when the key is OFF, to maintain clocks and computers, etc. In this case we expect that a few hours of riding per month will be all that is needed to avoid tending. If you know that you will go a number of weeks or months without riding, you can either attach a tender, or disconnect the negative cable from the battery. In any case, during storage you may use the voltage chart above and an accurate voltmeter, and consider recharging when the battery is around the 50% capacity remaining mark, or above.


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In doing some more reading I have discovered that Shorai recommends their charger to charge their batteries for the simple reason that all cells are not charged equally with any standard type of charger. Equal cell charging is the optimum situation for extended battery life. What about the mortorcycle itself? It is emmulating a conventional charger (connected to the +ve and -ve battery terminals only). The other feature the Shorai charger has is a storage mode. When run in storage mode the charger discharges the battery down to the optimum storage voltage. This is used when the battery is going to be inactive for a prolonged period of time (like a Canadian winter EH!). Supposed to prolong the life of the battery. I suppose if your going to spend that much money on a battery ($229.00 Cdn) you mite as will try and make it last as long as possible. Shorai is quite proud of their charger! Cost is approximatly $100.

I guess i'll find out if they are worth it or not.... I just put one in my bike. Can't believe the weight of it. Feels like an empty battery shell!



Cheers!

Bruce
 
Let us know how it works out over the long term. Maybe update this thread every so often to give us your impressions (the good and the bad).


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If information is power, maybe we could try starting our bikes with a USB cable plugged into this forum.:idea



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