"Battery Tender" questions

I'm with ya VTBeemer
Spent Memorial weekend installing P3 Brake Lights, an IQ-170 Lighting Controller, BlingLights LED driving lights, two 6 LED strips low on the inside front fender and an AutoSwitch AS7 to kill the lights if needed. I drained down the battery during the install by 2 days of turning on/off the ignition without starting the 08 RT1200. At some point I switched on the Grip Heaters and the bike wouldn't start for the test ride. Soooo I plugged in my trusty trickle charger to the front PowerLet Socket. Of course the AutoSwitch LED lit up, telling me it was being powered up by the battery charger. It was flashing from quick pulses to steady red about every minute, obviously it didn't like the charger!
I cut the quick disconnect off the $25 PowerLet adapter and engineered my own Charging Pigtail. I found a existing 1/4 hole in the Fairing Mount and slid my Heat Shrink Covered charging wire through the hole and connected to the battery. I left the cable room to slide in and out a inch or two for use. It slides back in and tucks under the Passenger Seat where the Seat Heater Switch is mounted. Works Great!

I just ran an SAE tender pigtail off of the battery. Took all of about 30 seconds, and I don;t have to worry about it. I can power my Slime compressor from it as well.

05Train said:

I just ran an SAE tender pigtail off of the battery. Took all of about 30 seconds, and I don;t have to worry about it. I can power my Slime compressor from it as well.

Click to expand...

Fused I hope.

Tender for F650 GS

I would like to buy a tender for this bike, and believe that BMW makes one that plugs directly into the accessory socket. I cannot find it on their website and so if anyone can tell me about these, what they are called and where to buy one or at least view it online I would appreciate it .

Thanks,

Grant

I have Odyssey batteries in all three of my motorcycles. I have been riding my 04 Roadster the most, and as such I let my two Kawi Cruisers sit,[my bad] and the batteries went dead. Plugged them in to a B/Tender for about 24 hours each, and both started effortlessly.

gfergeson said:

I would like to buy a tender for this bike, and believe that BMW makes one that plugs directly into the accessory socket. I cannot find it on their website and so if anyone can tell me about these, what they are called and where to buy one or at least view it online I would appreciate it .

Click to expand...

If you really want the BMW name you can find it here: http://www.ascycles.com/detail.aspx?ID=2678 as well as other places. The key to your google searches is to add CANBUS to the search terms, i.e BMW CANBUS battery charger.

Another charger that can also plug into your accessory socket at about 1/3 the price of the BMW charger is the Optimate 4 dual (must be the dual version to work via the accessory socket of your bike). Example: http://www.amazon.com/dp/B004PPXZIA

Battery Tender Question

BMW Triumphant said:

My new bike came with a dealer installed pigtail connected to the battery with an SAE connector to accommodate a battery tender unit. I did not request this and only found out about it when I took a pigtail in with me at the 1000 km service. When I asked them to attach it, they showed me their standard item already installed.

I have the Sr unit that has a storage mode - Jr probably does too. Just leave it connected all winter.

Click to expand...

I dug this quote from an old post regarding late model bikes with on board computers and it sort of answers my question regarding battery tenders. It appears here that the selling dealer has connected a pig tail directly to the battery whereas allowing the owner use a more conventional battery tender as opposed to spending $166.95 for BMW's battery tender like my son in law bought for his GS.

In order for this to work properly the ignition key must be on when it is plugged in, afterwards the key can be turned off and the BMW battery tender will now talk to the computer and battery.

I know the owners manual says to disconnect the battery when connecting a battery charger to the battery to prevent damaging the electronics. However 12 volts is 12 volts, it does not matter where it comes from, so please can anyone explain how this type of connection can damage the electronics.

I have had several cars which were full of electronics and jump starting or charging was never an issue. In view of the BMW dealer making this connection the owners manual appears to be designed to sell BMW battery tenders.

What are your thoughts on this, I am not happy buying a 166.95 charger for my 2008 R1200 RT when I have three regular battery tenders here that work.

Thanks

GeneT said:

However 12 volts is 12 volts, it does not matter where it comes from, so please can anyone explain how this type of connection can damage the electronics.

Click to expand...

Actually low 14s.

The only way that battery voltage can increase is by applying a higher charge voltage to it.

Furthermore, any sensitive electronics if it is properly designed would have filtering and over-voltage protection.

Attach the charge harness to the battery directly and stop worrying. Cripes, your alternator produces far worse voltage to the battery and your electronics is just fine...thanks to that big capacitor called a battery.

Gotta love the scare tactics used.

Battery Tender

Thanks Global Rider, since I posted this I found another member that has made this same connection with out any problem.