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putting the bike on battery tender

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4.6K views 10 replies 5 participants last post by  daduqueb  
#1 ·
On my previous bikes (oilheads, airheads, K75), I used to plug the battery tender into the accessory outlet when I needed to keep it charged.

So far I've been riding the F700GS at least 2 days a week and haven't have to use the tender, but I imagine at some point if I may have to put it on the tender.
Is it ok to plug the tender into the accessory outlet? Or do I need to hook it up direct to the battery? I can always wire a pigtail to make it easy.

Thanks, V.
 
#2 ·
If going through the BMW connector beside the ignition I understand that you will need a Canbus compatible charge system, like the Optimate 4 that came with my bike. BUT, these chargers don't push the voltage past about 13.8V.... and a regular charger will get up to 14.3V or more.

My 2014's OEM battery has failed, despite spending much of its life attached to the Optimate . The wife's 2013 battery, on the other hand, is doing fine.
 
#3 ·
You can use a $150+ BMW "smart" charger connected through the power port - or you can connect a pigtail, with an SAE connector, directly to the battery posts and hook up any other brand maintenance charger. The choice is yours. [;)]
 
#4 ·
In CANbus mode the Optimate 4 will not exceed 14.4V. You can do the connection direct to the battery but you should ensure that the battery charger will not exceed 14.4V. In particular you have to be wary of "intelligent " chargers that may decide that the battery needs to be desulphated by hitting is with high voltage pulses.

Sent from my SGH-I747M using Tapatalk
 
#5 ·
In CANbus mode the Optimate 4 will not exceed 14.4V. You can do the connection direct to the battery but you should ensure that the battery charger will not exceed 14.4V. In particular you have to be wary of "intelligent " chargers that may decide that the battery needs to be desulphated by hitting is with high voltage pulses.

Sent from my SGH-I747M using Tapatalk
Why would that be an issue for the battery? Thanks, Greg
 
#6 ·
I have a 20 year old Deltran battery tender - a trickle charger. When I spoke with Deltran cust svc, they confirmed that the batter tender would work fine with any of the newer batteries. I guess I'll connect a pig-tail to the battery.
 
#11 ·
I keep my bike on a battery tender constantly because I don't get to use the bike that much. Any how I keep it constantly connected to the battery because the BMW connect wont accept the "Powerlet Battery Tender & Yuasa Charging Cable" bought at amazon. Guys at BMW told me I should connect tender straight to the battery and works great!