RE: Battery/Charger problem HELP - 2

According to the BMW parts website, the replacement battery for the 2021 R1250RS is the same as all prior year watercooled RSs.

That's true for the R1200 ST from 2005 up to my 2017 RS - I ordered two last march from nippynormans and they sent me the same unit for both bikes.

This afternoon's update on my situation.

I removed the battery. Quite surprised that it's NOT the smaller weight/BMW cost saving battery !!! There is NO foam pad and it takes up the entire vertical and horizontal space in the battery compartment !
Hooked up the BMW charger to it and after two hours I was amazed to see it fully charged at 100 %. SO, it was not failing.
IMHO there are two possible explanations for what occurred over the weekend.
1. The onboard computer controls that accessory power socket. It could be erroneously blocking the charging. BUT yesterday the voltage right at the battery was 14.4 while connected to the charger. ???

I noticed last year the center two positive terminal brass tangs in the socket were separating. That was most likely caused by removing the charger before a ride, connecting an accessory plug and removing it after every ride, and reconnecting the charger after every ride. I suspect that loose connection may have something to do with this event but I am leaning to the computer control being a cause. What do you guys think ??

I bought a spare socket from Bob's BMW online last year at a sale. The list price was$54 last fall !!!
Installed the new socket today. Once the charger goes into sleep mode this evening will disconnect it.

Will install the battery tomorrow morning and take a ride. Hopefully when back the same scenario won't repeat itself ! Fingers crossed !!

Tiger,

Can you post a picture of this full-size battery?

I like to go to this website to see which batteries will fit my motorcycles. Here is a link to batteries that fit the 2016 RS: https://www.batterystuff.com/batteries/m.../2016/r1200s-r/

Attached is a photo of the battery on the charger.BMWbatteryToday.jpg - Bild entfernt (keine Rechte)BMWbatteryToday.jpg - Bild entfernt (keine Rechte)

From the top of the sealed cells caps to the bottom it is 5 3/4” tall and 5 3/4” wide
And 3 1/2 deep
just disconnected the charger that has been at 100% charged for over 2 hours
Voltage with no charger 13.48 volts

Zitat von Tigervette im Beitrag #4

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The computer in the cycle does use power when not running and it does run the battery down....

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You seem comfortable taking the battery out and replacing it in its "Moray Eel" hole- a tight affair on my 2016 R1200RS.
That's a good habit, as far as I'm concerned. I didn't attach any pigtails, fuses, don't have a proper special DIN-plug "optimate" or BMW fancy charger, etc.
I just take the battery out and put it on a trusty battery tender as needed.
My 2nd much-better-than-crappy-defective-OEM is an O'Reilly's auto chain super start AGM motorcycle battery. It's been perfect 3 years running, and it didn't require any removal and topping off with charge in the winter.

I'd continue to watch your battery under your charge routine and think about taking the dealer parts guy's offer to have it specially load tested.
You could have a sketchy cell. Easily. It will show 100% charge and the correct voitage, but may not be able to serve the current under load out on the road.
A good load tester should pick up intermittent bad cell behavior.
My OEM cell would behave where the start button was pressed and the dash lights would flicker, but no crank, no starter motor. Then seconds later it would deliver a normal start.
No other charging system warnings or lights of any kind.
Then it stopped starting altogether.

I had no such flukes, weirdness with the replacement O'Reilly's battery.

It's interesting that the markings on the full-sized battery are English and Russian. I don't think I've ever seen that on any OEM parts.

Supply chain issues, I guess.

What labels are on the other (terminal) side of the battery?

on the other side of the battery is a label, all in some foreign language with a specs. chart for the battery, volts, amps, etc.

Zitat von Tigervette im Beitrag #25

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on the other side of the battery is a label, all in some foreign language with a specs. chart for the battery, volts, amps, etc.

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For what it’s worth, if the battery size hasn’t changed since 2018, the ETX 14 from Big Crank fits and under $100.

https://www.batterymart.com/p-Big-Crank-ETX14-Battery.html

While I struggle with the hypothesis of battery heating resulting from a conductor fault in the DIN accessory plug receptacle, I would suggest the OP should forget he has that feature on his bike. Mount one or two SAE/12vCoAX/CTEK/NOCO accessory pigtails to the battery (using the frame-mounted positive post). Cost per SAE pigtail is less than $10. That way, he avoids any issues with the CANBUS system.

Before I update today's diagnosis results, can a BMW charger be connected directly to the battery while it's connected to the cycle using the last poster's connection point ??

I ask because I installed the battery this morning. Started normally. Took a 40 mile ride, stopped to refuel. It restarted OK. Volts during ride was 14.3-14.4. Came home 5 miles later. Immediately put on BMW charger to the side accessory outlet. After about 10 minutes charged to 94%. As of now, 2 hours later, charger still shows 94%, 0.6 A 14.4 V. Temp of back of charger now 119 F, top of battery around Neg. post 105 F. Voltage at battery using Neg. terminal and side red cap positive post reads 14.33 V.
As I asked above, to determine if the on board CPU is blocking the charge, should and CAN I safely connect the BMW charger to the neg. battery terminal and Red capped positive post next to the battery ??

Otherwise, my only other hypothesis is the battery is failing and should be replaced after a dealer special tool battery tester.

Another BMW dealer website stated "the OEM BMW cycle battery on all new BMW cycles is warranted against defects in material and workmanship for a period of 24 months (unlimited mileage) from the date of purchase....OTC purchase of original BMW batteries are also covered by a 24 mo. warranty." They stated if you bring it in and have it tested that results in a reading "replace battery" you will get a new battery free.
Does this policy still stand ???