rain kills battery???

[Jerry G Turner]

I have a walmart battery in my magna little over two years now still working good .

[hootmon]

Motobatt from Amazon in wife's Sabre.. couple years... Still good...

[Magnum Magna]

I now have a voltmeter so I am always looking for anything out of the ordinary.

[tedkraus]

The new battery from Advance Auto Parts is a Magna Brand, the clerk "highly recommended", most important though it was pre-charged and had 12.5 volts, and 335 cold cranking amps when checked. It also came with a 12 Month unconditional warranty. So I am looking forward to not having it fail until the 13 month on the first day. 

[Lurkin]

Unless you install a voltmeter, I don't know how one would anticipate battery failure, even if it were "gradual".  By far the most stress on the battery is in starting, so I would expect it to eventually fail to start the bike.  Even though this appears sudden and catastrophic, I suspect if we had better monitoring, we would see that is not the case.

It's not clear to me how a voltmeter will predict a bad battery?  When running, a healthy charging system will show normal voltages even with a bad battery.  Most of the "bad" batteries that I have measured have been capable of showing 12-13v, but have no amps behind it.  Am I missing something (...related to this thread anyway  )

[lragan]

It's not clear to me how a voltmeter will predict a bad battery?  When running, a healthy charging system will show normal voltages even with a bad battery.  Most of the "bad" batteries that I have measured have been capable of showing 12-13v, but have no amps behind it.  Am I missing something (...related to this thread anyway  )

There are two primary failure mechanisms for the cells in a battery --

1) Low impedance (nearly a short) caused by collection of conductive debris between the plates.  Usually from solids that collect in the bottom of the battery.  In this case, the charge voltage will not reach the 14-15 volts that a healthy battery will show when the charging system is in its specified output RPM range (above about 3000 rpm in a 3rd gen Magna).  The current limit of the charging system will be reached at lower voltages.  The battery can overheat and boil over in this case.

2) High impedance (approaching an open) -- caused by plate erosion or bad connections.  In this case, the voltmeter will show 15-18V while charging, and the voltage when not charging will sag below 12V -- to 11V or even 10V. 

Of course, there can be a sudden change to either condition, usually caused by a hard jolt, but if the objective is to catch gradual degradation before the battery fails to start the bike, a voltmeter is the simplest game in town.

I guarantee that a bad battery will not show 12-13V when placed under load -- as when you try to start the bike.  The voltage will sag to something much lower.

[hootmon]

I know about the solids on a wet cell battery, but is that possible in a gel battery? Just wondering..

[lragan]

Possible?  I don't know, probably possible, but not nearly as likely. 

I don't have a lot of experience with gel cells, but the only ones I have used have eventually developed a high impedance, so the battery slowly seems weaker and weaker.  Kids' riding toys typically are powered by gel cells, as they are safer.

The MC battery I have in the red bike now is a gel cell.  I suppose time will tell.

[ggeezer]

Batteries can be a real pain. I've had instances where all was normal in the morning and you go out in the afternoon and the battery is dead... of course, it's a week after the guarantee has expired.
The worst case scenario was my wife's new Mustang GT. Every once in a while it would not start. I take a voltmeter to the battery and it's dead. Since it was still under Ford Road-side-assistance, we had it towed to the dealer three times. At the dealership, it would start normally... they can find nothing wrong and consider you an idiot. After the third time, I forced them to change the battery and everything has been OK since. I suspect the battery developed an open circuit somehow and the jiggling of being towed would fix the problem temporarily.

All this begs the question:
The maintenance-free battery in my Honda VTX 1800 is 10 years old and still works great  but when is it going to fail? Probably at the worst time. The dilemma is "should I change a perfectly good battery just because it's old or be a cheapskate and wait until it fails"?

Orv.

[roboto65]

Me I vote for cheapskate LOL mine do not get changed till they die 

[tedkraus]

Me I vote for cheapskate LOL mine do not get changed till they die 

I guess I vote for the cheap way also... Just hope it doesn't die when there is no cell service in the middle of nowhere...

What I have done in the past if it shows signs of death I would change it. My car battery was really weak, I could tell slow cranking and hard to start when cold, I charged it up on my variable charger. While I saved up for a week or so for a new battery... When I returned the core to the auto parts shop they could not believe my car was still starting on the old one when they checked the voltage and CCA.