Battery Mantainer

Hi Everyone,
I need to get some input, on my 2016 R1200RS I want to get a battery maintainer. One dealership tells me only the BMW one that plugs into the port can be used because of all the electronics. Another dealerships tells me a battery tender will work fine that's what they use on there sales floor, any input would be appreciated.

One of the most popular and most recommended of these devices is the Battery Tender, Jr.

http://a.co/24Icw9L

You would need to connect the included SAE pigtail to the battery (easy), and could eventually use that same pigtail to power your heated jacket by adding a SAE to Coax adapter.

The BMW one works well but its main benefit is that you would use the bike's power port, which is not possible with BT Jr.

If you add an SAE 2 pin pigtail to your battery you can use a battery maintainer designed for AGM batteries. Make sure to use one that does NOT have a high voltage desulfation mode, which spikes the voltage too high.

You want your maintainer to charge at about 14.4-14.8 volts and hold at 13.6 to 13.8.

I measured my stock RTW last week and it only draws about 1 mA with the key off so only loses about 5% of the battery’s charge every two weeks. So if you ride once every two weeks you may not need a charger.

sailorlite said:

One of the most popular and most recommended of these devices is the Battery Tender, Jr.

http://a.co/24Icw9L

You would need to connect the included SAE pigtail to the battery (easy), and could eventually use that same pigtail to power your heated jacket by adding a SAE to Coax adapter.

The BMW one works well but its main benefit is that you would use the bike's power port, which is not possible with BT Jr.

Click to expand...

The Battery Tender Jr. has too low a trickle charge voltage for an AGM battery. There are other better units.

FWIW the BT Jr's manufacturer has this to say about use with AGM batteries:

"Perfect for all lead-acid, flooded or sealed maintenance free batteries (AGM and gel cell)."

A principal difference between this unit and others is that this one is slow, as in overnight or slower. Many riders prefer a more powerful, faster charging model.

Now, another option is the Optimate 4 Can Bus edition. I have 2of these and they work great. Amazon for about $79. I also have the Bmw charger as well as a battery tender JR connected with Sae direct to battery and a regular battery tender. As stated previously , the battery tender can not plug into the Bmw port. You need to use the sae pigtail option. Either the Optimate or Bmw charger will plug in and talk to the canbus


Sent from my iPad using Tapatalk

brianhinton said:

Now, another option is the Optimate 4 Can Bus edition. ...

Click to expand...

I've had one of these for years, on three successive BMW Canbus RTs. Look no further.

Brand X at $29.95 or brand Y at $79.95. One distinction.

Might charge to 90% vs might charge to 98% on a given battery. Another distinction, based on charger voltage.

Will charge a depleted (left the GPS on) battery in 4 hours vs might charge it in 10 hours. Another distinction.

Pick your poison.

Alas - in the last 5 years battery charger threads have erupted like oil threads or tire threads. Most folks like what they bought

I have at least 5 different brand/types of chargers for motorcycles. Tender. Tender Junior, Optimate, Schumacher, etc. I keep at least 6 bikes on chargers for parking/storage most of the time. I go out - start the bikes, ride away, and smile. Some are cheap. Some are not. Read the favorites with a grain of salt.

sailorlite said:

FWIW the BT Jr's manufacturer has this to say about use with AGM batteries:

"Perfect for all lead-acid, flooded or sealed maintenance free batteries (AGM and gel cell)."

A principal difference between this unit and others is that this one is slow, as in overnight or slower. Many riders prefer a more powerful, faster charging model.

Click to expand...

Yes, they do say that. Just measure the voltage at the battery after the charger is in long term maintenance mode. The BT Jr. is in the low 13s, and you want high 13s. If the BT Jr is now high 13s you’re good to go.

Personally I have no favorite charger to recommend, just one with enough voltage. The less you ride, the more it matters since the charger is doing most of the work to keep your battery healthy.

Here is my charger, I can set the voltage and monitor the charging current. It works on all my bikes, cars and boats (even an offshore lobster trawler once with 500 lbs. of dead batteries that limped to port). It’s cumbersome to use but always charges to 100%. It cost $44.95 on eBay and delivers up to 10 amps. On an AGM battery I start at 14.6-8 volts and reduce to 13.8 for maintenance charging.

CTEK MUS 4.3

https://www.amazon.com/gp/product/B006G14FK8/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1


Harry

I would forget using the bikes plug to connect charger, why to many issues,
Wire direct to battery with a fuse either a SAE OR POWERLET CONNECTOR, I went with a powerlet and OPTIMATE4 on all my bikes. Also doubles as a power scource for heated gear and Tire inflator, neither of which will function from factory plug, current RT is my 6th Bmw to have this done

roger 04 rt said:

Yes, they do say that. Just measure the voltage at the battery after the charger is in long term maintenance mode. The BT Jr. is in the low 13s, and you want high 13s. If the BT Jr is now high 13s you’re good to go.

Personally I have no favorite charger to recommend, just one with enough voltage. The less you ride, the more it matters since the charger is doing most of the work to keep your battery healthy.

Here is my charger, I can set the voltage and monitor the charging current. It works on all my bikes, cars and boats (even an offshore lobster trawler once with 500 lbs. of dead batteries that limped to port). It’s cumbersome to use but always charges to 100%. It cost $44.95 on eBay and delivers up to 10 amps. On an AGM battery I start at 14.6-8 volts and reduce to 13.8 for maintenance charging.

View attachment 65918

Click to expand...

How well would this work as a "maintenance" charger for a bike parked for 2 or 3 months?

battery tender plus !

When inquiring about this subject with my local bmw dealership, he advised to go with the battery tender Plus and not the junior model. Bike at the time was 05 GS and now 2014 1200gsa. ...
13 years later. ....no issues. Just sayin'

PGlaves said:

How well would this work as a "maintenance" charger for a bike parked for 2 or 3 months?

Click to expand...

Depends on whether the ripple voltage is high enough to achieve desulphation yet low enough to be safe for on-board electronics.

PGlaves said:

Brand X at $29.95 or brand Y at $79.95. One distinction.

Might charge to 90% vs might charge to 98% on a given battery. Another distinction, based on charger voltage.

Will charge a depleted (left the GPS on) battery in 4 hours vs might charge it in 10 hours. Another distinction.

Pick your poison.

Alas - in the last 5 years battery charger threads have erupted like oil threads or tire threads. Most folks like what they bought

I have at least 5 different brand/types of chargers for motorcycles. Tender. Tender Junior, Optimate, Schumacher, etc. I keep at least 6 bikes on chargers for parking/storage most of the time. I go out - start the bikes, ride away, and smile. Some are cheap. Some are not. Read the favorites with a grain of salt.

Click to expand...

Paul ... this is a great response! Totally agree. My poison for years has been the BWM Tender similar to the Battery Tender plugged into a battery pigtail. Have also used regular Battery Tenders all without fail. Never had a bike fail to fire up. But like oil ... they all work just pick your poison.

gsinnc said:

... they all work

Click to expand...

True, as evidenced by the fact that whatever battery you have (flooded, gel, agm, LiFePO4), our bikes only have one charging system and it will keep any of them in operation if you ride the bike occasionally. Sure you can tweak the regulated voltage up or down to better suit one type or the other, but it will "work" where it is.

just pick your poison.

Click to expand...

I think a better summary is "pick your duty." There are chargers, there are maintainers, and there are charger-maintainers. A "trickle-charger" is just a small charger subject to all the limitations of such. There are "smart" and I guess stupid versions of each. If you put a simple "charger" on your bike, whether large or small, and leave it there you will eventually damage the battery. That is what a "maintainer" is for. A "maintainer" can be left connected, but a "charger" cannot. The answer, of course, for a "charger" is just to use it intermittently during long storage. You can also get by with doing nothing - until the battery's self-discharge plus parasitic drain drains the battery to the point that it will not start the motorcycle - and after storage it could take a bit of cranking to wake it up. There is a special hell awaiting those with "Classic K" bikes who try to start their bikes with a weak battery and find that it welds the starter relay closed and goes into Chernobyl mode. Whether that is a week or three months depends on your particulars. Disconnect the battery during storage and parasitic drain is removed (but not self-discharge, which is different for each chemistry). Eventually at low charge levels with any lead/acid battery, sulfation will begin. Odyssey or WallyWorld, chemistry is chemistry. It is best to keep that from happening but possible to reverse it if it hasn't gone too far.

The technology-specific chargers and maintainers are simply optimized for the particular chemistry to charge the battery as fully and safely as possible. If the goal is "as fully and safely as possible" then there are very different parameters for each. LiFePO4 being the most different from mainstream, but even between the lead/acid variants there is enough difference for a manufacturer to deliver a difference in performance by catering to the specific chemistry. I have an EarthX LiFePO4 battery in my R12GS and it lives tethered to an Optimate Lithium maintainer. It thinks all the time about stuff I don't want to be bothered with and the different lights go off and on telling me how hard it is working. Fine. It works. The battery likes it and I don't have to worry about it. If it doesn't think the battery needs anything, it will even go offline without me unplugging it (but it will still keep an eye on the voltage). I have lots of AGM's on other motorcycles and lawn equipment. They all stay tethered to their own BatteryMINDer 2012-AGM Charger-Desulfator. My farm equipment and automatic propane generator all have flooded batteries. Some of the farm equipment has big diesels that might not get started for long periods of time. The generator self-tests every Saturday morning. I'd hate to hear it go "runk-runk" and give up at 2AM in the middle of an ice storm. They all stay tethered to their own regular BatteryMINDer 2012. They are happy as well and have been for many years.

And yep, I still keep an old cheap dumb buzz-box charger around for when someone leaves something on and drains the battery to the point that the smart charger refuses to clock in. Cars that get used regularly don't get anything, but in my most humble of opinions, all this occasional use stuff can benefit from a good battery maintenance regimen. Ignore it, do it manually, or let a bunch of smart little dedicated boxes think about it.

I guess after all those words, @gsinnc is right... pick your poison.

Most riders who ask the question “what maintainer should I buy” want to keep their battery fully charged. If that’s the case, purchase one that correctly matches your battery’s charging requirement, as described by the battery manufacturer. (If you only want to be sure to have enough charge so it will start and you don’t care about battery life, pick what you like or use what you have.)

This is a much less important decision on a Wethead because its charging system is designed for an AGM battery and riding will fully charge it (although that’s not true on an Oilhead) even if your charger/maintainer can’t.

The other thing to consider on a stock Wethead is that it only seems to draw 1mA (as measured on mine) with the key off (about 1/3 of an Oilhead) and as a result can easily go 2 weeks without any charging (even a month in a pinch).

If you’re buying from scratch, there’s no reason not to buy a charger that matches your bike.

roger 04 rt said:

If you’re buying from scratch, there’s no reason not to buy a charger that matches your bike.

Click to expand...

That CTEK I provided a link to has a "mode" button. One of the modes is a motorcycle symbol - for smaller, motorcycle batteries. The charger can handle any size battery, but it will be kind to smaller motorcycle batteries. I believe the CTEK is a "maintainer."

<iframe width="854" height="480" src="https://www.youtube.com/embed/HFzYNvj6_OY" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>

Harry

Just for Thought...

You should consider that when you rewire your plug directly to the battery on your in-warranty BMW in order to use an aftermarket charger, you might be giving your dealership cause to void your warranty should an electrical problem arise.

roger 04 rt said:

Yes, they do say that. Just measure the voltage at the battery after the charger is in long term maintenance mode. The BT Jr. is in the low 13s, and you want high 13s. If the BT Jr is now high 13s you’re good to go.

Personally I have no favorite charger to recommend, just one with enough voltage. The less you ride, the more it matters since the charger is doing most of the work to keep your battery healthy.

Here is my charger, I can set the voltage and monitor the charging current. It works on all my bikes, cars and boats (even an offshore lobster trawler once with 500 lbs. of dead batteries that limped to port). It’s cumbersome to use but always charges to 100%. It cost $44.95 on eBay and delivers up to 10 amps. On an AGM battery I start at 14.6-8 volts and reduce to 13.8 for maintenance charging.

View attachment 65918

Click to expand...

PGlaves said:

How well would this work as a "maintenance" charger for a bike parked for 2 or 3 months?

Click to expand...

Hi Paul, It works fine but I plug this manual power supply into a weekly timer for a 6 month layup. But this is just something that works for me in the garage not something I’d advocate.

On my boat with three large flooded lead acid batteries I like the MinnKota charger. It measures battery temperature and adjusts the voltages accordingly. It also disconnects after 24 hours of trickle charging and waits for the battery voltage to dip a bit before going back into charge mode.

My Generac generator is another matter, it constantly charges the battery with a true trickle charge that boils the battery. I’m trying to figure out how to rewire the controller so I can use a MinnKota there too.