Battery Appears to Not Be Charging

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I wouldn't be so fast to involve a dealer in any of this ... So far it does not sound that bad ... Yes, 2/100th is insignificant ...

The term you used "high power lights" has me intrigued ... How high power ? Do you run them while riding ? Do you know what they draw ?

It would be really nice to see what voltages you see in the system "while riding" .. Hard to do with a hand held volt meter ... I have a digital one on the face of my tank bag that I plug in when on long trips so I can be clued in to the health of the system and get a early warning if voltages are off ...

Battery tender makes a thing for doing that for a few bucks ...

Do you have any way you might easily see the voltage while riding ? That would definitely tell you if you need a regulator ...

 
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SO it looks like a replacement to get this thing to work (assuming the R/R is the problem,) is $129. Where on the bike does the thing live? How much plastic has to be removed? No garage, driveway project?

 
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They're the PIAA lights. I don't know what they draw. Good question about what they draw. I don't know, they are PIAA E-13. I have the wiring harness instructions which indicates "For lamp systems with bulbs of 130 W x2 or less. When the original battery died, I definitely had riden with them on. Yesterday with the new battery, I'm not sure.

In terms of seeing the voltage while riding, I guess I could just run the bike for a while in my driveway. Unless of course, the theory is that road vibration is causing a connection to temporarily come loose. I will look into the battery tender connector. I guess you're talking about this: https://www.batterytender.com/Accessories/Digital-Voltage-Indicator-with-LCD-Display.html

Eric

 
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I'm 99.9% sure it's not the r/r. Your bike is charging. It's either a break in the wiring somewhere or something is drawing it down when it's off.

 
I can't find that specific light online. They sound like automotive lights to me and definitely not low wattage led.

If those draw a ton of power, you could easily drain your battery unless you were at a sustained high rpm.

I would figure out their exact draw, and if they were installed correctly.

In the mean time, go for a ride and stay close to home. Keep the lights off and measure your battery before and after the ride.

It should be apparent if the battery is getting run down during the ride if the voltage is less than when you started.

 
The Gen II fjr (starting in 2006) had more excess electrical capacity than the Gen 1 bikes. Gen 3's have even more. Gen 1 bikes have the least.

I could easily see those lights exceeding the capacity of your charging system. Especially if you were running at a lower rpm.

Just remembered that you said you had a Gen 1.

Still no closure for you but, it is a reasonable theory.

Food for thought. Report back to us.

We will get it figured out one way or another.

 
OK, back from a thirty minute night ride. Before starting, battery showed 12.70 volts, down from 12.74 but still probably not consequential. Rode with PIAA lights OFF. Came back, pulled key from ignition and tested.... 13.0 volts. The only plausible theory seems to me to be that those PIAA lights were in fact on yesterday (even though I would have sworn I had them off) and that they DO exceed what the generator puts out thereby draining the battery. Delran BatteryTender digital voltage indicator arrives from Amazon on Wednesday which I guess will enable me to test this theory unless anyone here has any other ideas. Oh and yes, this is a 2005 bike.

When Amazon gets the Anti-gravity Micro start XP 3 in, I think I'll celebrate not having to figure out how to install a new regulator/rectifier or stator and buy one.

Eric

 
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I'm thinking that the lights are the issue too, especially since everything else is stock. I wired mine to a relay that let's my aux lights go on and off with the headlights. No fuss no muss. If that's what's happening then with the lights on you're drawing more than the bike puts out. The Gen 1 has enough extra amps for just the lights.

 
The PIAA lights have to be switched on manually and I was pretty sure I had them off yesterday when the new battery died. There are no other accessories. Maybe tomorrow if I hvae ants in my pants about the voltage indicator, I'll go out for the same ride with the PIAAs on and test the voltage when I come back. BTW, that radiator fan seems to draw a lot of power as well. I pull the key right away when I stop to keep it from killing the battery.

There's definitely a jump start battery in my future.

 
The PIAA lights have to be switched on manually and I was pretty sure I had them off yesterday when the new battery died. There are no other accessories. Maybe tomorrow if I hvae ants in my pants about the voltage indicator, I'll go out for the same ride with the PIAAs on and test the voltage when I come back. BTW, that radiator fan seems to draw a lot of power as well. I pull the key right away when I stop to keep it from killing the battery.
There's definitely a jump start battery in my future.
The fan draws a lot of power but it doesn't (shouldn't) run very much if the bike is moving. Practically the only time my fan(s) run is when I'm idling in traffic on a warm day.

The jump start device will get you going if you have an "Oh Shit" moment when you ran the lights too long or otherwise drained your battery. However, the jump start is only there for an emergency. If you rely upon it frequently, your battery isn't going to last very long. Repeated deep discharges of AGM (or gel) batteries will kill them in fairly short order.

You need to find out the total current draw of those Piaa lights and if the draw exceeds or even comes close to the Gen I excess charging capacity, you need to get rid of them in favor of some of the newer high intensity LEDs. Remember that the stated generator output is a maximum under ideal conditions (i.e. 4000+ RPM). Available watts are much lower at ~2000 RPM. Someone once posted an analysis of the FJR base load (so you could calculate available power for accessories) but I can't find it.

 
The PIAA lights have to be switched on manually and I was pretty sure I had them off yesterday when the new battery died. There are no other accessories. Maybe tomorrow if I hvae ants in my pants about the voltage indicator, I'll go out for the same ride with the PIAAs on and test the voltage when I come back. BTW, that radiator fan seems to draw a lot of power as well. I pull the key right away when I stop to keep it from killing the battery.
There's definitely a jump start battery in my future.
The fan draws a lot of power but it doesn't (shouldn't) run very much if the bike is moving. Practically the only time my fan(s) run is when I'm idling in traffic on a warm day.

The jump start device will get you going if you have an "Oh Shit" moment when you ran the lights too long or otherwise drained your battery. However, the jump start is only there for an emergency. If you rely upon it frequently, your battery isn't going to last very long. Repeated deep discharges of AGM (or gel) batteries will kill them in fairly short order.
I carry an XP-3 PPS under the seat, I highly recommend it. Good for all kinds of charging duties as well as jump starts. Why carry one? I'm still using my original OEM battery and expect it to quit without warning like my last 3 dead auto/pickup batteries did.

 
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There is no doubt that an auxiliary battery that is capable of starting the bike in an emergency is a good idea but only for emergencies and charging phones, laptops etc. It is not a substitute for inadequate power management on the bike.

 
As stated above, rated charging output is at 4000RPM which is basically highway speeds ... Or low gear around town ... Yes, the battery tender meter will tell the tale ...

I can tell you with certainty that everything that you have done so far is making sense and from where I am sitting it sounds like the bike is operating up to design spec. Either there is an intermittent short or other intermittent drain that we have not seen yet or the lights are the culprit.

As far as the first new battery, did you charge it to 100% before using it ? It could have something to do with the results you saw. Also, it is not necessarily odd for batteries to be bad right out of the box. It is reasonably common ...

Also, are those lights hooked up so that they can be turned on when the bike is not running ? That is the kiss of death from my perspective. That is asking for trouble. High draw items need to be powered via a relay that only allows current flow when the engine is running ...

Also, when you get the battery meter and start riding, the magic number is 12.8 volts. If your charging system is reading lower than 12.8 at the battery terminals, the system is not putting out enough current to supply your accessories AND charge the battery. At this point, the battery will begin to drain to make up the difference. If over 12.8, the system is putting out more power than the accessories are drawing and the battery is absorbing the excess (charging).

Mine usually puts out about 13.3 to 13.5 when I am riding around using my heated gear which draws around 60 watts or so ... I would expect yours to be in this range as well ...

After you get into this, maybe ride around at 2000 or 2500 RPM and power on those lights ... See what that does to the voltage ...

Here is a link to a graph showing the "state of charge" of a battery based on voltage measured at the terminals. https://www.marxrv.com/12volt/voltchart1.gif

Let us know ...

 
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This is enormously helpful. The voltage indicator arrives tomorrow and as you say, it should tell the tale. I DID NOT charge the battery when I received it but it read 12.84 AFTER my ride last night, up from 12.7 before I started out (PIAA lights were switched OFF for the ride). Thanks much, by the way, for the magic number specification.

Curious though, how would I know I have a bad battery? How would you test for that?

Full report tomorrow after the meter is hooked up.

Eric

 
Typically a bad battery might be "bad" for a variety of reasons. It might have one bad cell. There are 6 cells (2 volts each). If it was "charged" but only showed 10 volts or something that (could) indicate a bad cell. That is not too common.

The most common failure is for the battery to show full voltage but still fail to start the bike. This is where you might hear the "tick tick tick" in a car ...

Easily determined though ... Just connect the meter to the battery and see what the voltage is. Then try to start the bike (with the meter still connected) and see what voltage the meter reads WHILE CRANKING the bike ...

It should not drop much below 10 volts or so ... I don't remember the specific number but you can google it ...

Either way, if the voltage drops below that number while cranking, the battery is starting to go bad ...

Pretty simple to check for ...

 
Any auto parts store, Walmart can LOAD TEST the battery for you (for free).

It should be fully charged and off the charger for at least 1/2 hour.

Slow, 1.25-1.5 amp charger (automatic) is the best.

 
The votes are in.... First, much thanks to this forum for all your help. Now to the matter at hand. I hooked up the voltage indicator and started up the bike. It showed 14 volts once the engine came down to idle. Then, I switched on the PIAA lights and the voltage dropped to 12.8, then 12.7, then 12.6, then I got scared and switched them off. At 2500 RPM with the lights on, the indicator read 13. Then it occured to me that prior to parking the bike on Sunday, when the problem arose, the group I was with was stuck in 20 minutes of grid locked traffic. Undoubtedly, I had the PIAAs on (inadvertently) and drew power from the battery to keep them running. Right after the traffic, the bike was switched off, so the battery was never replenished.

Lessons learned: Mind the new voltage indicator. Mind the PIAAs and use them only on the open road (not a big issue for me, I don't really need them at all). Ask the forum!

THanks to everyone who helped me troubleshoot this.

Eric

 
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When you have money and time, switch out the PIAAs for LEDs. You'll never have to remember any special details about the aux lights.

 
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