Battery draining right before my eyes

[Regular Guy]

Hi guys, have any of you ever seen a battery drain as soon as you take the tender off of it? The reason I ask is that I am having some sort of issue going on where I HAVE to leave the bike on a battery tender. Today I pulled the tender off and measured volts at 14.3 after it sat for a few seconds. Started the bike and revved it up to 2500rpms and it stayed roughly the same. I then revved it up to 5000rpm and it stayed the same. By all indications, the charging system is working (according to the Fault Finding Flow Chart that is stickied on this page.

I turned the bike off, unplugged the gps/cell phone holder/charger I installed to make sure it's not trying to draw power. I tested the battery connections again and saw the volts dropping right before my eyes, quickly! I have yet to take the R/R off completely but will attempt to do it this weekend. I've seen videos on how to test it.

My question is, can a bad R/R cause the battery to drain when the bike is not running and key off or is there some other avenue I need to explore? Also, as I posted in another thread, I recently noticed my LED tailight flickering. Could this have something to do with all of this? Maybe I need to solder my connections (which I meant to do anyway).

The bike only has 7900 miles on it and is a '99. Any help, as always, is much appreciated!

 

[Regular Guy]

I just went out and checked it after about an hour, it's at 12.4!

 

[Fire-medic]

Sounds like the battery is failing internally, and won't hold the charge. What does the voltmeter say when you measure the battery and crank the engine? What does the voltage drop-to?

 

[D-Max2012]

Can you clarify what you meant when you said you disconnected the GPS/ Cell phone charger?
Note that all batteries will settle down to their rated voltage after being disconnected from a charger. It's how long it holds that rated voltage (without a parasitic drain) will let you know if the battery has any issues.
The reason I asked about your GPS / Cell phone charger is this: GPS / Cell phone, or any other USB device runs off of 5 volts DC. The Bike uses 12 volts DC.. So, when installing a USB device / GPS unit, I always connect it to a KEYED power source, like the Head Lamp or something that ONLY turns on, when the key is ON.. That little box that connects to your battery is a step down transformer. It brings the voltage down from 13.8V to 5V. Problem is,, The instructions tell you to connect it directly to your battery.. Because it is a self contained unit, it doesn't care if you have a Cell phone or GPS unit connected or not.. It's still converting 12v to 5V, = Draining your battery. Hope this helps..

 

[davesax36]

That 14 might just being the charging voltage and skin effect from the tender. 12.4 sounds fine to me. Also, you might check to be sure your attachment point for the charger stuff isn't the problem. Brian (Redbone) had this happen with his, and had to just disconnect the whole apparatus before our trip last year. Some of those adapters draw a couple volts all the time for whatever reason.

 

[Regular Guy]

I am doing an experiment as we speak. I am going to leave the tender off of the bike when I go out in a couple of hours and see where it's when I get home tonight. If it's below 12.xx I'll charge it up again and disconnect the gps charger. Which, btw, has an on/off toggle switch that glows blue when on. As for a connection point, I connected it to the battery tender positive and ground (IIRC). It has a wiring harness that I can disconnect easily but I wouldn't think it would draw being that it has its own proprietary on/off switch but maybe it still does? We'll find out soon enough....stay tuned!

 

[D-Max2012]

Which, btw, has an on/off toggle switch that glows blue when on.

That all depend on how that switch was wired from the factory.

IF your switch is located at position #1, this equates to a parasitic drain problem.
IF your switch is located at position #2, This will cut off power to converter box without loss of functionality or battery drain. (Best Setup).

 

[Regular Guy]

Hmm...well the converter is on the device itself as is the switch.

 

[D-Max2012]

If you can give the name of the device, maybe we can look up its wiring.

 

[Fire-medic]

What is the lowest reading on the voltmeter when you have it hooked into the positive side of the battery in series and crank the starter?

 

[MaxMidnight]

With everything switched off I would first start by checking to see if you have any parasitic drain from the battery.

If there is then you would need to isolate the source.

If none then fully charge the battery the disconnect and leave for 24 hours. Take a reading or perhaps more relevant, try to start the bike.
Depending on the type of battery you have then a reading of below around 12.5 or 12.6 volts is not good. If it won't crank then the battery is probably Donald Ducked

 

[Regular Guy]

If you can give the name of the device, maybe we can look up its wiring.

Sure thing, it's this one :

https://www.amazon.com/gp/product/B017UC20QC/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

 

[Regular Guy]

Okay gents, here's the current (no pun intended, or is there?) status. I just went out and checked voltage after letting it sit all night w/o the tender. The battery is at 12.68ish. I started her up, no problem. Turned over easily. I had the volt meter on the battery terminals and did the 2500rpm test. It climbed to 13.8ish and stayed. I then ran her up to 5000rpm (which is loud in a garage BTW, those Delkevics make some racket). Voltmeter stayed at 13.8ish. So other than stinking up the garage with exhaust smell, it seems to be acting normal. I think the whole problem may have been the shitty battery tender I have been using. That coupled with the fact I've not been riding much at all due to one excuse or another I think explains my issues. This new battery tender is a Noco Genius and it's awesome!

Things may change but for now maybe I'm good? I'll give another update once I get some miles on her. Now that my Wife has her bike back it's gonna get some wind time.

 

[davesax36]

Good. It's nice when the electrical gremlins move out on their own.

Sent from my STV100-2 using Tapatalk

 

[Fire-medic]

NOCO makes battery chargers that work on lithium ion batteries too, you just have to choose the correct one. One charger for lead/acid, AGM, or Li-ion, a good way to go.

 

[Regular Guy]

NOCO makes battery chargers that work on lithium ion batteries too, you just have to choose the correct one. One charger for lead/acid, AGM, or Li-ion, a good way to go.

Yeah, this one has a Li-Ion setting. That is indeed a cool feature. My brother turned me on to Noco. He has a basic model Genius and loves it.

 

[D-Max2012]

❷WIRING NOTE: Red line connects to the positive output lines of the electric door lock, black line connects to any negative line on the motorcycle. No need long wires and suitable for all motorcycle models. But before wiring, find the correct positive output lines of electric door lock is very important.

What Door??
Hope you got it nailed down..

 

[Regular Guy]

What Door??
Hope you got it nailed down..

I assumed the rear hatch? lol! Yeah, those damn Chinese always messing with us

 

[sdt354]

I'm running a Lithium. I've never had it on a tender.It has sat for 2 months at a time and fired the bike up. If I drain it from a bone head act like leaving the key on, I use a regular charger at 10 amps for an hour. When your charging system is operating, there's no special provision for a Lithium battery. So I've not been convinced to spring for a special charger yet. When Gel Cell battery's came out, there was a 3 step regulator required by vendors. But the shop charger was nothing different. Certainly no harm done.

 

[D-Max2012]

I'm running the Shori Lithium also.. No need for a special charger.. The DO warn that if you plan to use a regular charger for this Lithium Iron Phosphate battery, DO NOT use a charger that uses a DeSulfication mode charging method. http://www.upsbatterycenter.com/blog/battery-desulfation/
Again, This is NOT recommended for Lithium batteries if you have / or plan to get one.

Note1: It's is Not recommended to let a Lithium battery completely drain. Once below a certain voltage per cell is reached, the over life of the pack is compromised.
Note2: Lithium batteries has a much Lower Self Discharge Rate, (LSD rate), than Lead Acid - So you can find a Lithium battery that sat for months, and still crank the bike over without a problem.
Note3: Motorcycle Lithium batteries uses the existing charge system of the bike. No special device needs to be added.
Note4: When cold, a Lithium battery will not put out its maximum power output, BUT, Once allowed to internally warm up, (Turning on the lights for couple of minutes), you can find the Lithium will crank over stronger, than 1st attempt.
Side Note 4b: Listen to the bike when 1st start is attempted when it's cold outside. Don't keep cranking it.. Turn on the lights and give it a couple of minutes.