Harley Davidson Forums - How long would you expect a new battery to last with lights left on.

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Quote:

Originally Posted by ROCKOUT Rocker Products (Post 17442352)

I'll also add...

I had a relatively new Yuasa battery (the big bad model) in my '15 Limited. Used to be able to leave it parked 3 weeks or more off the tender no problem. Then I had a water pump go out on the road... multiple short cycles of ride a little, shut it off & let it cool, ride, cool, ended up having it towed home. It sat there for 2 weeks while I gathered parts & the time to fix it. The battery was completely dead. Charged it up but it was never the same again... a week off the tender & it would hardly start the bike.

That's the first bad review of a Yuasa I've heard of. They are generally good batteries..

About 30 to 40 minutes

Quote:

Originally Posted by TriGeezer (Post 17442398)

since it happened to you, how long did it go?

I did not want to influence anyone’s initial replies.
The ignition was left in the on position for about 30 - 40 minutes tops.
The Dyna has the worst battery box design.
There is little to no clearance.
normally I would of just popped the battery and shot back in an hour or two with a charge on the battery.
I was so annoyed with it being a new battery, I just took the car out that night instead.
With all the computers and electronics on cars and bikes, they take a lot of amperage to get them going, but I was still shell shocked at 30 - 40 minutes.
A half hour seems to be the consensus thus far

Quote:

Originally Posted by upflying (Post 17442132)

You got to wonder why Harley Davidson hasn't developed the technology to kill power after 5 minutes of sitting parked with the ignition switch on.

Yes, this is a feature I would dearly love to have. I left my lights on one time. My bad. Effed up my whole day as I discovered that no one but the dealer knew how to tow a motorcycle.

Quote:

Originally Posted by Allfields (Post 17443746)

Actually, all the computers take small amounts of amperage, but are voltage draws, and as voltage drops, the ability to hold thresholds of voltage (approx. 9.5 V) for them to operate, the chance for the bike firing, gets slim fast. The quality of your battery, the state of charge in the beginning, temps, etc., all play into the length of time your battery will be able to deliver power. Not all batteries are create the same..

Pulled my bike out of the garage to do some work in the garage and left the ignition on for about 1.5 hours.
Battery dead as a door nail.
Charged it back up and no worries.
That was 6 years ago with the stock Harley battery.