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New Battery...drained '15 F700GS

kyylieeeeee

New member
First, I would like to say I have literally no clue what I am doing with electrical nonsense. I have a 2015 F700GS with 16700 miles. Only thing added is some fog lights, they've been on since before I bought the bike a year ago and never had issues before. No other chargers or farkles plugged in.
It still had the original battery that I knew was in need of replacing. On Monday, finally died such that turning the key wouldn't even light up the dash let alone turn over (and Battery Tender Plus wouldn't pick it up - only got a flashing red light).
Replaced the battery on Tuesday with a brand new one from Beemer Boneyard, all seemed promising. Bike started right up, tender said it was fully charged. Yay!
Switched the tender to another bike for 24 hours, and by this morning, the battery was completely dead again (dash not even lighting up - just nothing when I turn the key). Hooked up battery tender, started charging up (solid red light for a bit). Checked an hour later, and battery tender was blinking red-green-red-green, which I've never seen before - the internet says that I've perhaps hooked up the polarity wrong, which I know...isn't what happened. So, I've disconnected everything for now.
I've got a pickup scheduled from the MAX BMW service shop in two weeks, but in the meantime, trying to figure out what might be happening...
On a totally unrelated note ;) if anyone would like to purchase this bike, I am in lower NY.
 
Getting 6 years out of a battery for these bikes isn't too bad. Was the new battery fully charged when you put it in the bike? Did you just start the bike for a couple seconds to verify it worked, or did you ride it for a while?

Using a multimeter will give us some great insight - do you have access to one?
 
Was the new battery fully charged when you put it in the bike? Did you just start the bike for a couple seconds to verify it worked, or did you ride it for a while?

Using a multimeter will give us some great insight - do you have access to one?

Hi, thanks for your follow up questions...I'd hooked the battery up to my Battery Tender Plus, and it read as fully-charged within a few minutes, then popped it in the bike. I had the bike on for about 5 minutes, but did not have a chance to ride it; planned to ride it the following day, but alas, completely dead within 24 hours.
Going to get a multimeter this weekend, unfortunately I am out of town all week.
I took the battery back out of the bike and hooked directly to the BT, and same thing happened. Solid red for a few minutes, then red-green flashing. I am 100% certain that the polarity was hooked up correctly in both instances.
So, now I'm feeling like I've got a defective bike, battery, and battery charger! :laugh
 
Hi, thanks for your follow up questions...I'd hooked the battery up to my Battery Tender Plus, and it read as fully-charged within a few minutes, then popped it in the bike. I had the bike on for about 5 minutes, but did not have a chance to ride it; planned to ride it the following day, but alas, completely dead within 24 hours.
Going to get a multimeter this weekend, unfortunately I am out of town all week.
I took the battery back out of the bike and hooked directly to the BT, and same thing happened. Solid red for a few minutes, then red-green flashing. I am 100% certain that the polarity was hooked up correctly in both instances.
So, now I'm feeling like I've got a defective bike, battery, and battery charger! :laugh

I think red-green flashing does not mean charged battery.
 
Many auto parts stores will test a battery, including under load, for free. I would not tell them your entire story, only that you are having trouble. It is not common, but not out of the question that a new battery is defective. At least you will know.
 
New batteries do not come fully charged. Even if it read fully charged, I would still leave a new battery on a charger for a full 6-8 hours or overnight before trusting it.
 
FWIW-

If you connected the battery wrong, it will blink red then green alternating colors. This red-green blinking means you hooked up the battery "polarity" wrong.

:dunno

OM
 
I've just received the bike back from service, and learned a few things. The CANsmart is what failed and was constantly draining the battery. For now, I've disconnected it and will look into a new setup for my fog lights.
After successfully hooking the Battery Tender Plus up to another bike with no flashing error lights, I learned that the battery being completely dead will give the reversed-polarity blinking lights. That one's not listed in Battery Tender's user manual, so no wonder I couldn't find it.
SO ends this saga for good, I hope. Now on to decide on some new tires, but I've still got a few miles before that needs doing...
 
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