What kind of battery for adventuring, is Lithium up to the challenge?

[JoelWisman]

Originally Posted by Mike.C

You're scaring me Joel!

I put Shorai's in both our F658's before shipping them to New Zealand for Christmas. So now the question is what regulator should I install as I really like the weight saving, and where to get it. Don't want to shove this excellent thread off topic so I think I'll post up a sep[arate one for that question.

Really appreciate your effort, really intersting even more important enlightening.

Give me a day to see if I can find one of the many excellent regulator/rectifier manufactures willing to put on an oe direct replacement plug.

I'd also like to talk to a few engineers about series rather then shunt regulators, as that is one possible way to deal with rapid stator heat aging.

This isn't likely critical yet. Lost Rider, the owner of the Shorai I found to be so unbalanced has been the first to experience many F800GS problems. It will take time and a lot of cycling before these issues show up for others.

Lastly I think it wise to wait for some more data points on what charging voltages are being seen on K7X bikes, as NCD's post has given me pause.

[NCD]

This morning - the standing voltage displayed on the Bug is 12.8, and my multimeter says 12.86.

Battery is the OEM Deka (black top, textured grey sides.)

[JoelWisman]

Originally Posted by NCD

This morning - the standing voltage displayed on the Bug is 12.8, and my multimeter says 12.86.

Battery is the OEM Deka (black top, textured grey sides.)

That sure sounds accurate. The question is, are you the only ones or do others have this higher charging voltage?

Anyone with a charging voltage at or above 14.2 don't really need to worry about a Shorai getting unbalanced.

[ebrabaek]

Originally Posted by JoelWisman

That sure sounds accurate. The question is, are you the only ones or do others have this higher charging voltage?

Anyone with a charging voltage at or above 14.2 don't really need to worry about a Shorai getting unbalanced.

I am in socal until this Saturday 3/22..... I will measure mine as soon as I get home.....

Erling

[JoelWisman]

Originally Posted by ebrabaek

I am in socal until this Saturday 3/22..... I will measure mine as soon as I get home.....

Erling

Aren't you home yet??????
Im filled with suspense.

If I got this wrong and most F8's are charging above 14.2, well, that changes one of my concerns a lot!

[ebrabaek]

Originally Posted by JoelWisman

Aren't you home yet??????
Im filled with suspense.

If I got this wrong and most F8's are charging above 14.2, well, that changes one of my concerns a lot!

... You and me both...... Still here.....in Socal, were told yesterday to prepare to stay until Sunday...... Arrrrggggg... The suspense is killing me......


Erling

[Apostolos]

I've got the battery bug installed and my charge is the way Joel describes. Fluctuates between 13.8-14.1 while riding around, and up to 14.4 at idle.

God bless,
David

[ScienceOfDirt]

Bike running. See picture for RPM, temp, and voltage reading. This was after a short ride home for lunch. Bike is a 2010 vintage. Let me know if I can get anything else.

From Forum

[JoelWisman]

ScienceOfDirt, can you check the voltage with the RPM's around 3000.

[ScienceOfDirt]

Just for more data, the voltage was 14.11 at 2000 RPM, and 13.99 at 3000 RPM.

[JoelWisman]

Originally Posted by ScienceOfDirt

Just for more data, the voltage was 14.11 at 2000 RPM, and 13.99 at 3000 RPM.

0.15 volts higher, but still the behavior I am used to seeing. If you ride like I do, rarely idling, this is a voltage range that will cause issues with Shorai batteries unless you change the voltage regulator or use a balance charger every month or two.

Thanks for the data.

[Mike.C]

Here are the voltages as best as I can measure them with the equipment I have.

Bike: 2010 F650GS
Bike was idled for 10 minutes before readings taken
Meter 1 (red): AMPROBE PM51A and according to their spec sheet accurate to +- 2%. (brand new and bloody expensive by my standards)
Meter 2 (Yellow): Digitech QM-1525 (old, cheap and shitty)
Ambient temp: 25 degrees C
Installed Battery: Shorai LFX18A1-BS12
Idle Voltage: M1 - 14.1v, M2 - 14.01v
3000RPM Voltage: M1 - 13.99v, M2 - 13.9v

Lower voltage at 3000 RPM compared to idle seems odd.

Proof of test pics follow.

M1, Volts at idle


M1, Volts at a tad over 3000rpm


Meter comparison at Idle


Meter comparison at 3000rpm



Ambient temp

[Eurastus]

I've got an early 2009 F800GS that was purchased in October of 2008. This was roughly the 800th bike off the assembly line, if I'm reading the VIN correctly.

Multimeter reads 14.07 volts at idle and 13.88 at 3000 RPM.

This seems in line with what Joel reported at the beginning of this thread.

I'm starting to think there was an in-line change to the OEM regulator made sometime in the past several years; it looks like the newer bikes are consistantly putting out slightly higher voltages.

Thoughts?

[JoelWisman]

Outstanding

I thought I might be loosing my mind, but looks like NCD's bike has a BMW test regulator in it or for whatever other reason is an outlier.

Either way, it is ALWAYS a good idea to check idle and mid RPM voltage on your individual motorcycles before making decisions.

Mike C. I think your old, cheap, and shitty Digitech meter might be more accurate then your Amprobe LOL, though the Amprobe sure is cute and accurate enough for most things. 13.84 volts is normally what I see at 3,000 RPM and it has seemed consistent across all the F8's I have measured.

Lower voltage at higher RPM when the alternator isn't fully loaded isn't odd, its wrong. Without getting overly technical, the R/R BMW selected for these bikes is quick to sense and slow to adjust. It should be ignoring the peaks and shooting for an average RMS voltage of, well 14.4 volts in my book, but 14.1 if BMW was thinking the bike was going to be released with a gel battery. What happens with this R/R is it senses the peaks (harmless, actually beneficial) and drives down the RMS average to keep the peaks around 14.1 volts. It's a design flaw or at least a mismatch of regulator to charging system with a lot of electrical noise.


Apostolos thank you.


ebrabaek, I still want to see what you measure, partially for another data point, but more because I am curious what kind of meter you use :)

Mike C. From tests I have now done with two Shorai LFX18 batteries, doing something seems warranted. Balance charging every couple of months will suffice and would be the cheapest solution, or replace R/R's.

I am still waiting for 3 R/R manufactures to get back to me. I talked to sales support at all 3 companies but what I need to speak to is an engineer for each. Took a bit to confuse each companies tech support and convince then I really did need an engineer and that allowing me at one would only take up 15 minutes of their time and could be profitable. Will update on what kind of a regulator will work best as well as exploring series regulators as soon as I learn something more.

Thanks all, finally got back my high current and accurate clamp from repair and calibration since my shunts demise, more on cranking, pulse, CA, and CCA soon, and expecting to receive an AntiGravity battery and toss it into the mix of tests soon.

[JoelWisman]

Originally Posted by Eurastus

Multimeter reads 14.07 volts at idle and 13.88 at 3000 RPM.

This seems in line with what Joel reported at the beginning of this thread.

I'm starting to think there was an in-line change to the OEM regulator made sometime in the past several years; it looks like the newer bikes are consistantly putting out slightly higher voltages.

Thoughts?

I measured a 2012 F800GS just last week, results are buried somewhere in the middle of this thread, but it was pretty much the same as all the older K7X bikes I have measured.

I think we are just seeing inaccuracies of various multimeters except for one outlier which has WAY higher voltages and is stable through all RPM's

Thanks for the data Eurastus.