Battery discharging whilst parked over 3 weeks. Is this normal?

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feejer222

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I have had 2 battery's go dead. The first over a 2 hour period and the second over a 2 day period. The dealer has replaced the battery each time as neither would recharge.

I don't know if I had left the parking light on on either occasion, obviously now I will make a very concious effort not to. The dealer has tested everything and can find no other drain than the immobiliser. He says that this will flatten the battery over 3 weeks if the bike is left. Is this correct?

Also because the battery is a gel type it won't re-charge when completely discharged, and a new one is required,is this right?

I have a slow charger for the winter and will now put this on whenever the bike is left for more than a couple of days.

 
My 06 sat idle in my garage for about four months and started up fine. I checked the battery on the voltmeter before, during and after starting and didn't see anything abnormal. Makes me doubt the dealer's claim that the immobilizer will flatten the battery - as far as I know the only active drain is the flashing led and that stops after a day or two of inactivity so that it doesn't drain the battery.

As for the gel-type battery not taking a charge once it's fully discharged - having had to replace two of them on my FZ6 my personal experience with this type of battery is that it's true.

 
I have had 2 battery's go dead. The first over a 2 hour period and the second over a 2 day period.
There is a problem with your bike, or you have crook batteries.

I have often left mine for a month without riding or starting it, no problems.

Once I let it sit for 11 weeks, but it still started and ran fine.

 
Feejer222: If your shop checked so that there is no drain on your battery through a switch, light, ignition.and your battery is good and still goes dead It is your charging system the alternator has a bad diode that is draining your battery replace that, problem solved . Many service people overlook that as a problem..

weekend rider :D

 
Thanks for that guys. Great that we can always rely on this place eh?

You confirmed what I was thinking myself.

Weekend rider: Thanks I will mention that if it happens again.

 
Feejer222: If your shop checked so that there is no drain on your battery through a switch, light, ignition.and your battery is good and still goes dead It is your charging system the alternator has a bad diode that is draining your battery replace that, problem solved . Many service people overlook that as a problem..
weekend rider :D
Uhh . . anything discharging the battery (such as the charging system) would be a load and would be measurable.

If the first battery drained in 2 hours it was either finished or something absolutely was left on.

Does the charging circuit work properly? Does it float the battery to the right voltage? If you aren't getting enough volts, battery capacity will be compromised.

My bike sat from January 7 to April 20 and started right up - and there's an alarm system on it that does pull some small amount of current beyond the basic stuff like the imobiliser and memory in the ECU.

I am more impressed by the fact that this dealer replaced the batteries on a 2 year old machine apparently under warranty!!

 
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Feejer222: If your shop checked so that there is no drain on your battery through a switch, light, ignition.and your battery is good and still goes dead It is your charging system the alternator has a bad diode that is draining your battery replace that, problem solved . Many service people overlook that as a problem..
weekend rider :D

I am more impressed by the fact that this dealer replaced the batteries on a 2 year old machine apparently under warranty!!
Um....easier to change the battery then have to think and repair something?

 
Feejer222: If your shop checked so that there is no drain on your battery through a switch, light, ignition.and your battery is good and still goes dead It is your charging system the alternator has a bad diode that is draining your battery replace that, problem solved . Many service people overlook that as a problem..
weekend rider :D
Uhh . . anything discharging the battery (such as the charging system) would be a load and would be measurable.

If the first battery drained in 2 hours it was either finished or something absolutely was left on.

Does the charging circuit work properly? Does it float the battery to the right voltage? If you aren't getting enough volts, battery capacity will be compromised.

My bike sat from January 7 to April 20 and started right up - and there's an alarm system on it that does pull some small amount of current beyond the basic stuff like the imobiliser and memory in the ECU.

I am more impressed by the fact that this dealer replaced the batteries on a 2 year old machine apparently under warranty!!
Thanks for the input Frank. The bike was bought new on March 1st this year. It has been on the shop floor for 18 months.

 
Standard Yamaha issue I suspect. I didn't ask to be honest, left it to the dealer. I know that they are gel, but not what make.

The bike has run great all weekend, I will leave it now until next week and try it.

 
Bram frank: Yes their is a drain on the battery ever so slight and not measurable . It is an accumlative effect of the drain when then ignition is turned off. The drain is still taking place even when the electrical system is charging. there is enough volts and amperage to negate the drain but the drain is still there. Since the postive terminal from your battery is attached to your alternator the discharge takes place after the ignition key is turned off. The drain starts out ever so slight you may not get a reading on a multi-meter. As time goes on the discharge gets worse and becomes more noticable and the battery is drained much more quickly. Remenber when the bike has been run and the battery is at full charge it has more potential than the drain but as time goes on and the bike sits there the voltage loss and and amperage loss becomes greater than the stored battery voltage, thus resulting in a weak battery or a dead battery. To tell if the battery is good or bad here is a fool proof way to check it . Charge the battery up full 13.5 volts hok up you volt meter , now crank your bike over and read your volt meter . If your volt meter reads drops say to 12.8 volts your battery is good. If your volt meter reads say 10.7 to 11.9 battery is week may need a little more time on the charger, but it is definitely is going bad and like real soon. Now of you read 7 to 9 volts your battery is ready for replacement.

This way of checking your battery is much superior than a load tester

I know some will doubt this method of checking a battery so did I, until I started using it for trouble shooting it works and it is a proven method. Learned it from an elect. engineer offerring an electrical class for automotive repair

Just remember you are working with electricity and many many different thing can happen some we have not even come accross of yet.

B frank we are working with dc voltage and if the system was working properly we would not have a problem. Since the battery is going dead there must be a drain whether small or a large amount of leakage the question is where is it going? Dc voltage tries to get back to its original source unless interupted which would be a ground fault condition. This fault condition is not enough to trip a fuse, here you have to use OHM's law to calculate the amp draw to see if you would have enough potential difference to blow a fuse.

Bram, I am not trying to be a smart ass just some good dialog about professional differences and and learning more information about how and why things work and do not work and offering up a different way to solve a nagging problem wit fool proof results.ie :batterycheck

I am not trying to hijack this thread by any means weekend rider

 
Don't take this the wrong way but . . . (in no particular order)

1. We have meters today that can measure microamps and instruments available that are orders of magnitude more sensitive - there really is no drain that can deplete a 12AH battery that is in good condition in 3 weeks that can't be measured. This translates into something like 23 milliamps to complete flat - about half that to 'discharged eough that the bike will crank slowly' - and 10 ma can be read by the cheapest of Radio Shack meters.

2. Batteries have internal resistance and suffer from what is known as 'self discharge'. However it takes more than 3 weeks for an automotive battery to self discharge.

3. No one suggested a short, per se. But 'crap' across the contacts of a switch can sometimes conduct enough to drain things without lighting them up enough to notice. - 23 ma at 12 volts is under a third of watt of draw.

This is one reason why navigators that have internal batteries must be wired to a switched source of power.

4. One battery reportedly drained in 2 hours - that means somethng more than 4 amps of drain (assuming a good battery) and THAT is somethng more than 48 watts.

5. The charging system has diodes in it and the leakage is normally low enough that the draw is less than the self-discharge rate of the battery itself - I suppose it is possible that a diode in the regulator pack is defective (I did ask about the charging system). But even so, the drain would be measurable, given the 'time to flat' reported by the owner.

6. The bike was a leftover 2005 model - the original battery may well have been toast (or close to it) when he took possession of the machine. But the replacement ought to have been good.

 
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