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Battery tender hook up leads

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Yeah, my little battery tender Jr. only works for a couple of minutes and then cannot connect. Guess I have to buy a more expensive charger that will wake the bike up. Any ideas other than the currently out of stock BMW charger?
 
If you’re using the plug next to the reverse lever , it powers down a few minutes after you switch off the ignition. You would need to Buy the BMW tender it’s designed to be used there . Find were the positive battery cable hooks up just below the 40 amp fuse directly on the right side opposite of the reverse lever . You can hook up your positive side of your tender . And then hook up the negative lead directly to the battery . Any Battery tender will work in this way.I hooked up my Harley Davidson tender I had left over when I switched to the R18. Works perfectly .
 
I tested my OEM BMW trickle charger on both the R18 B (AGM type battery) and the FE (Li battery); both batteries were recognized by the charging via the plug just below the Reverse lever. Both bikes have been sitting for a few days..

The bike must have some smarts to it..??

I can see the charger report the battery voltage and then I can see the charge current value in Amps.
 
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Reedman71 said:
This seems to work…

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@Reedman71 I'm not sure if your bike is perpendicular to the ground, but your oil level looks too high based on the photo..? Maybe check and remove some oil if found to be in fact high..?

Also, the connection that you show in the photo - will absolutely work; you're basically connected directly to the battery terminals in that configuration..
 
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R2K said:
I think you folks may be making a mistake. The Auxiliary port is shut off by the CanBus a few minutes after the bike is turned off and you cannot use a standard charger such as a battery tender to maintain you battery. It will not be able to provide current through to the battery. You must connect a standard charger direct to the battery. If you have an Optimate or BMW OEM charger that is able to communicate with the Canbus and open the circuit then you can change and maintain the battery with Auxiliary port.
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I have an Optimate 4 (tm350) connected to a 2022 R18 B.
When the bike is off, the Optimate does nothing, when I turn the ignition on it starts working and charging. Once I turn the ignition off, it stops charging after a few minutes.

Could this be because of the installation of Jekyll & Hyde exhaust?

Have used the same optimate on my previous bike, R1200RT for years.
 
benalla said:
I have an Optimate 4 (tm350) connected to a 2022 R18 B.
When the bike is off, the Optimate does nothing, when I turn the ignition on it starts working and charging. Once I turn the ignition off, it stops charging after a few minutes.

Could this be because of the installation of Jekyll & Hyde exhaust?

Have used the same optimate on my previous bike, R1200RT for years.
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I can’t imagine it has anything to do with exhaust install or modifications. Are you sure you have the Optimate set up for the BMW CanBus charging? I believe in the instructions there are selection buttons for charging different systems and battery’s? Not an expert on Optimate but I believe I read that somewhere.
 
I have a 2022 R18 B with the Jekyll & Hyde exhaust and currently use the BMW charger, which can charge an AGM battery, as well as Li battery; however, I have to set the battery type within the setup menu.

I plug my charger into the DC socket, located just below the Reverse lever; perhaps, you're using the socket on the dashboard?

Have you tried connecting your charger directly to the positive terminal and the ground terminal located underneath the RH side cylinder; or perhaps, bypass the CAN BUS altogether and add a pre-wired charger pigtail?
 
I did use the socket below the Reverse lever, at the left side of the bike.
Also tried the one on the dashboard.

Today I will try to connect direct to the battery.
Which terminals are you talking about? Where exactly are these?
 
There is a (+) Positive Terminal used for jump starting a bike on the Right Hand Side (RHS), located just below the seat and slightly forward of the fuse block access side panel (you Do NOT have to remove the side panel); my bike has a RED plastic cap that covers the Terminal.

The (-) Negative ground terminal lug is located under the RHS cylinder; there should be something in the owners manual that covers jump-starting the bike.
 
I ran a pigtail to the right side and hid it behind the cover. Positive got attached to the jump pin, and negative to the screw for the tool cover panel closest to it. But mine is a FE, so way less electronics involved. I'd be more careful if I had the B or TC...
 

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R2K said:
I think you folks may be making a mistake. The Auxiliary port is shut off by the CanBus a few minutes after the bike is turned off and you cannot use a standard charger such as a battery tender to maintain you battery. It will not be able to provide current through to the battery. You must connect a standard charger direct to the battery. If you have an Optimate or BMW OEM charger that is able to communicate with the Canbus and open the circuit then you can change and maintain the battery with Auxiliary port.
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Yup.
 
Mine, (21FE) has a battery tender lead at the right side cover, zip tied to the frame rail.

I hope the PO made use of it, as the bike sat in a garage from early 2021, until last week, accumulating only 176 miles, my battery is old, but still holds a charge.

Greg
 
I took a look at mine, It's a Drag Specialties branded plug, and it looks to be a little more water tight than the Battery Tender branded ones, as it has a rubber seal as compared to plastic. And as stated earlier it's tucked behind the frame tube just in front of the right side battery cover.
 
Tim's R18FE said:
I ran a pigtail to the right side and hid it behind the cover. Positive got attached to the jump pin, and negative to the screw for the tool cover panel closest to it. But mine is a FE, so way less electronics involved. I'd be more careful if I had the B or TC...
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Thx for this. Was looking for a ground on the right side…, For a battery tender, that ground doesn’t need to be stout.
 
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