Battery Question

[stamen]

How long(approx.) should a battery that is in good condition, hold its charge say between 12.4-13.4 Volts when left unhooked from a charger or bike. Once it has been fully charged***

[XRorXB]

If you have a sealed AGM battery, the numbers I've read are a very low 1-3% self discharge rate each month. Much better than lead acid.

[GAXB9R]

Don't put it on the ground. Will discharged quicker over time. Not sure of an answer for your question.

[stamen]

Isn't an AGM battery still a lead-acid just that the electrolyte is absorbed by fibers separating the plates instead of just floating.

[uly luigi]

yes, but they don't discharge as fast, and don't put it on the ground or a metal shelf/table, store it on wood

[go cytocis]

In my experience, ambient temperatures will greatly affect your results but in cold temperatures around freezing, you could safely expect to get your bike restarted after 2 weeks of sitting idle. After about a month without a charge you'll probably have some problems..

[Jerry C]

My 2005 XBcityX cut off on the way home, first the speedo and tact stopped working, then when I slowed down to pay a toll the bike stalled and would not restart. I noticed one battery cable was a little loose, so I tighted it and put it on a charge. The next day the bike started and ran ok. Could this have been caused by a loose cable?

[uly luigi]

yes, and if it was loose long enuff, may have taken out your VR.

[Jerry C]

I hope not , I replaced the VR and stator last summer.Thanks!

[go cytocis]

My 2005 XBcityX cut off on the way home... Could this have been caused by a loose cable?

With almost 100% certainty, yes.

[user_deleted]

How long(approx.) should a battery that is in good condition, hold its charge say between 12.4-13.4 Volts when left unhooked from a charger or bike. Once it has been fully charged***

Buell XB's on average draw about .10 of an amp when sitting and off. my personal experience with a decent battery such as BS, Deka, or Yuasa and NOT on a tender is that 1 month in a 60 degree shop seems to be about the limitations of time that said battery will crank a 1203 Buell. surely some will tell you they've gone 5 months or longer and bike started just fine...others will say 2 weeks and starter struggles. but the above has been my experience.

[user_deleted]

After about a month without a charge you'll probably have some problems.. [up][up]

[upperb]

As to the issue of batteries discharging faster if laid on concrete, I think that's a myth. I remember being told this as a kid growing up in my dad's truck repair shop. I couldn't understand why this would be so. I could understand that, if the concrete is colder than the battery, heat being conducted away from the battery to the concrete may affect its state of charge. I can't think of any other thing that would affect the charge.

Would one of you engineers out there weigh in on this? Thanks!

[go cytocis]

As to the issue of batteries discharging faster if laid on concrete, I think that's a myth

Good point upperb. I never really questioned it before but I think you're right. Assuming the concrete is the same temperature as the air, it will not cool the battery any more than the air will. Sure the RATE of thermal transfer between the battery and the concrete will be faster than from the battery to the air, but once the battery reaches ambient temperature, it should make no difference what it's in contact with.
I am happy to be proven wrong by anyone with a better grasp of thermodynamics than I have!