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Who needs a Battery Tender

I got mine from them last year on sale (but not at that good a price). Fast shipping too. I've used them several times.
 
Canbus friendly?

Now, will this battery tender work by plugging into the power outlet?

Will it play nice with the CANBUS or does it have to be charged from the battery?
 
I have this same unit. It does not have the powerlet adapter. I happened to already have it and Deltran and other places also sell it. It does have the alligator clips and o-rings to go directly on the battery. I don't know about the CANBUS part.
 
I use this unit on my R1200RT. It comes with a lead that has ring connectors for the battery at one end and an SAE plug at the other. The charger itself has an SAE plug that mates with the battery lead's SAE plug. A second lead is included that has mini-alligator clips at one end and an SAE plug at the other end. Connecting via either of the two leads mentioned above plays very well with CANBUS. How can you go wrong for 18 clams?
 
Now, will this battery tender work by plugging into the power outlet?

Will it play nice with the CANBUS or does it have to be charged from the battery?

This DOES NOT plug into a powerlet. You use a lead with ring terminals attached to your battery.

Personally, I think the (expensive) chargers that hook to the powerlet have a weakness in geographical areas where the power may go out. IIRC, if you are charging via the powerlet and the power goes out, the bike's computer may get confused and, when the power returns, not "remember" it should be charging. I believe this situation has lead to the owner being unaware that the bike's battery is flat.

Attaching the Tender's lead to the battery and tucking the lead under the seat is, IMHO, no big deal. I also have a tank bag that has power to is supplied by the Tender's lead and an SAE extension cable.
 
Personally, I think the (expensive) chargers that hook to the powerlet have a weakness in geographical areas where the power may go out. IIRC, if you are charging via the powerlet and the power goes out, the bike's computer may get confused and, when the power returns, not "remember" it should be charging. I believe this situation has lead to the owner being unaware that the bike's battery is flat.

That is true in at least some versions of the expensive BMW branded battery charger. The not quite as expensive Optimate 4 DUAL is reported to do the right thing.

I find an SAE connector wired to the battery works for the chargers I already own with the added benefit that I can use the SAE plug for things like an Air pump which draws too much current under load for the current limited accessory socket on my GS.
 
OK, I'm confused - a common condition.

I've got a new-ish 2011 RT that I'll put on a charger once the riding is over in November/December. I've used a Battery Tender JR on several bikes for years, but the new BMW has an AGM (Absorbed Glass Mat) battery, and some information I've seen says a regular charger should not be used on it. I'd like to just bring the power leads right out from the battery, bypassing Mr. Canbus, but don't want to cook the AGM.

So, those who are using this method, do you have the AGM-type battery?

pete
 
{snip}...So, those who are using this method, do you have the AGM-type battery?...{snip}

Pete -

My '09 RT has an Exide AGM that I have put on the Tender (wired directly to the battery) over the last two MA winters. No problem.
 
So, those who are using this method, do you have the AGM-type battery?

Yes. The AGM issue has nothing to do with being directly connected to the battery... it has to do with your charger. If your charger is OK for AGM then it matters not if it is connected directly to the battery or connected through the Accessory socket.

Just about any "smart" charger will be OK for your battery. If your charger is so old that it is a true trickle charger -- one that feeds a small amount of fixed current to the battery forever -- then you might have issues. Of course you would also have issues with such a charger on a flooded lead acid battery if you left it on the battery for long periods of time.
 
My BMW charger went kaput which is why I got the tender jr. They're both made by Deltran. I still had my powerlet lead from the BMW charger and plugged the tender jr into it with no problems. It is charging an AGM battery on bike that does not have have a CANBUS system.
 
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