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Battery Tender Jr.

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11K views 34 replies 17 participants last post by  2010hdultra  
#1 ·
Bought a brand new HD battery for the bike. Brought home, installed on the bike and hooked up to the BT Jr. Did not pay attention as to how long it took it to charge completely up, (solid green light).

Went for a ride today, came home and hooked up the BT Jr. Took it 45 minutes to go from solid red light to blinking green. Stayed blinking green for about 10 minutes until solid green,(fully charged).

Does 45 minutes sound too long for the initial red light to stay on for a brand new battery? If so, I wonder if I could possibly have some current somewhere that is drawing it down more than it should be.

Thanks in advance for any and all replies.
 
#2 ·
Shouldn't take that long at all. I'm guessing here that the battery was sitting on the stealership's shelf for a while and was down to begin with. The start took a little more off of the top, and if you didn't ride very far, it could have been a bit under full charge causing this. Keep in mind that the tender isn't supposed to be used as a charger per se but rather for keeping the battery "topped off" while it's waiting for you to take off again.
 
#3 ·
What type of bike. Different ones have different features and more parasitic drain when not running.
How long was your ride. It can take a little bit to recharge a battery just from starting the bike. Then figure, again depending on what accessories you have on the bike running while riding. Radio, etc. ....besides the headlight which is always on under normal circumstances.
 
#7 ·
I have the regular BT, not the "Jr.", and it sometimes will go from a few seconds of red straight to solid green, but can't remember it doing the flashing green. Is that something peculiar to the "Jr." version?
 
#9 ·
Mine is an older one (got it in '04). Looked at the faceplate, and it only shows solid red or green. Also flashing yellow which is the "OH s#!t " indication. The instructions that came with it are long gone.
 
#11 ·
Thanks, Brian and Joe. I suspect that is something in the newer units that mine doesn't do. I'll try calling the manufacturer tomorrow and see what they say about it just for the record.
 
#14 ·
I have both the regular and Jr. models. It's not unusual for the junior to work a little differently and do some different things, like blinking red after being on a battery for a few days. I don't know why but I've noticed it does it sometimes. No need to worry. Seems normal. I take the junior when I travel. BOL

2013 FLHRC
 
#17 ·
I've had a Jr. since '06 and have used it pretty much every night since then. It's been used on 3 batteries and two bikes. Mine goes from red to green, no flashing green. I've never seen it take more than about 10 minutes to go green. I would think that 45 minutes is too long.

I know that on my bike that the main reason for a higher idle (1000rpm) is to keep the stator in the charging range. I know of a couple of people who have lowered the idle to get the 'Harley' sound and then had trouble with the battery not charging properly if they were in a lot of stop and go situations.

Maybe have a load draw test done on the battery while it's still in the bike. If it shows a voltage draw then you know that something is eating voltage after you park it.
 
#20 ·
I have been using the Jr. since going to a Harley. Three bikes and four different batteries. I've had two of them. The first one crapped out from being ran over by my wife's car.

They commonly take 30-40 minutes to cycle to green light in my experience. Not all the time, but often.
 
#22 ·
OK, here's the latest on the saga. Went and bought a multimeter. Battery showed fully charged according to the BT Jr.(solid green). Let the bike set for over an hour after unplugging the tender. Bear in mind this is a brand new HD battery. Checked with the multimeter and battery showed to be 12.96 volts. Turned ignition switch to on position and meter showed 12.07 volts. Started the bike up and meter showed 13.65 volts at idle, (bike not fully warmed up yet and idle rpm around 1100. Could not get more than 13.75 volts anywhere from 2000 rpm to around 3000 rpm.......And get this, while I was doing all this, just for grins I checked my old battery that was sitting on the shelf with the meter and it showed 12.07 volts. Wouldn't that appear to be a good battery??

Now I'm going to check to see if there is a parasitic drain, but want to make sure I go about it right......I will disconnect the neg battery cable and hook up the meter to it and the other end of the meter to the battery terminal. Ok NOW I need a little information. I will need to switch the meter from DC volts to DC amps. Am I correct?

Once again, your help will be appreciated.
 
#23 ·
OK, here's the latest on the saga. Went and bought a multimeter. Battery showed fully charged according to the BT Jr.(solid green). Let the bike set for over an hour after unplugging the tender. Bear in mind this is a brand new HD battery. Checked with the multimeter and battery showed to be 12.96 volts. Turned ignition switch to on position and meter showed 12.07 volts. Started the bike up and meter showed 13.65 volts at idle, (bike not fully warmed up yet and idle rpm around 1100. Could not get more than 13.75 volts anywhere from 2000 rpm to around 3000 rpm.......And get this, while I was doing all this, just for grins I checked my old battery that was sitting on the shelf with the meter and it showed 12.07 volts. Wouldn't that appear to be a good battery??

Now I'm going to check to see if there is a parasitic drain, but want to make sure I go about it right......I will disconnect the neg battery cable and hook up the meter to it and the other end of the meter to the battery terminal. Ok NOW I need a little information. I will need to switch the meter from DC volts to DC amps. Am I correct?

Once again, your help will be appreciated.
Correct, DC amps.

You need to check your charging system, you're not getting enough voltage at 3000 rpm's . Should be 14.5 volts or better .

Your "spare" battery should be good, just charge it up with a battery charger, not a battery tender .
 
#26 ·
The voltage on a battery doesn't mean much. A DMM doesn't load it all when testing it. It could read 12.8 on a meter and drop to 3-4v under load.

And don't hit the the starter with the DMM between the ground and the battery. You'll cook it unless you have a nice Flug or similar that can handle a high amp draw.
 
#27 ·
And don't hit the the starter with the DMM between the ground and the battery. You'll cook it unless you have a nice Flug or similar that can handle a high amp draw.
Just to clarify, Don't hit the starter when checking amps. I think you'll even cook a Fluke DMM if you try to check amps and hit the starter button.

Checking voltage is ok as no current runs through the meter when checking voltage.
 
#28 ·
Mine does the same thing. After a long ride, the high-capacity, glass mat battery in my Dyna takes about 30 minutes to go to solid green. When the bike was new, it took the same amount of time, 30 minutes or so, to go to solid green.

I don't know why. The Dyna has a very robust alternator. The volt meter never shows the battery as discharging anytime during the ride, yet the battery tender always takes a little time to show that it is fully charged.

Pete
 
#32 ·
Batteries will show higher voltage when they are warm vs cold. So a battery fresh off the road, hot from engine and charging will show 13+ volts, then as it cools will drop slightly. So the slow rate of a tender or flaot charger will top it off without warming it up to give a false reading.

This also works if its cold outside, turn your lights on for about 1-2 minutes then start you vehicle, it will probably crank faster as the drain from the headlights it warms the battery up.
 
#33 ·
Bought a new HD battery and a new Battery Tender Jr. The light stayed red for hours. Returned the battery, had it tested at dealer. It was OK. Hooked up my other Battery tender Jr. from another motorcycle battery...went to solid green in less than a minute. I could not believe that the Battery Tender was defective...turned out that it was.