I have a 2011 Fatboy Lo. Lo Jack installed (new battery on key fob). Swapped the original battery out at the end of last year (July12) for a Brand new battery (X2 Power). I went out and bought a Harley tender and kept it plugged in all winter. It started right up in January so i decided to disconnect the tender. It again started right up (no tender connected) about a 2 months later. So I go to start her up again to go for a ride yesterday, and its dead. (Murphy's law FML!) Tried charging it at a slow trickle, and my charger gave me a 'Bad Bat' message. Took it into the store (Batteries Plus) where i bought it, and they said it charged up just fine. Going to pick it up today. Anyone ever had this issue, if so, any suggestions on how i can avoid having it continue to discharge on me?! Thx for the help!

 

Presumably disconnecting it from the charger allowed the alarm to flatten it, not sure if the battery is dead flat wether a trickle charger is man enough to recharge it.

 

great, thanks. so do you think i'm better off leaving the tender connected at ALL times? Don't understand how a brand new battery could drain so quickly.

 

The trouble with the new Harleys is that the alarm is armed as soon as you walk away from the bike automatically as I understand it, I've got an older bike that you have to set manually,which I rarely use as they're more trouble than they're worth, I don't know how much current the alarm draws but I would definitely leave it connected, if it still goes flat you've obviously got another problem, hopefully someone with a newer bike than mine will chime in if I'm wrong.

 

I have a 2013 road king with auto set alarm on her.
I leave my battery tender off the bike for two weeks and she startes right up.
Now if the temp.goes below 30 degrese after two weeks then she could use the tender charger.
So to answer your question if the alarm does draw power from the battery the answer is YES.
BUT so does the cold weather.

 

if its been sitting since january and not on the tender, it wouldn't surprise me that its dead at the end of march. theres always some kind of draw on the newer bikes even its only .030 MA (miliamp) and it will kill the batt. a tender won't charge a completely drained batt in short order, it most likely will take a few days to bring it back up.

 

I have a tender hooked up on boh of mine anytime they are in the garage.

 

Agreed. Why not keep the tender always plugged in. Thats their purpose. BTW, I got a Schumacher tender at Walmart.com for $20...Works great!!

 

These are my personal rules of thumb:

1. If I DO NOT plan on riding the bike within 1 week of my last ride I put it on the tender.

2. If I'm not sure when I'll ride again, it goes on the tender

3. If it hasn't been on a tender in the last month due to frequent riding, it goes on the tender.

4. In winter, which is December through February in Texas, I keep it on the tender continuously, whether I ride or not.

5. If the bike seems to crank more to start it goes on the tender.

All this talk of tender brings to mind...

 

Thx all for the help. Guess i'll keep it on the tender! great Elvis reference. lol