How many times can I kill the battery?

[SWbySWesty]

It's only happened on the trail once: Terrain so tough with an uphill battle where I stalled so much that I killed the battery. Had to drag the bike around and bump start it going down. Then twice I've let the bike sit too long without a ride and I killed the battery getting her started (ie: this morning). How many times do you think I can cycle a small battery like this before it gives up? I usually ride everyday without a problem, but in the event that I get a tough section, I want my battery ready to start the bike multiple times! :roost:

 

[Cabrito]

I'm going to think it depends on the overall condition of the battery, and battery type.

On my KLR I can turn my headlight off, and I do this when I'm doing lots of slow speed riding off pavement. I heard once that if you are not keeping it at a high enough RPM it won't charge the battery (not sure this is true) - Also if the headlight is off then maybe it's easier on the battery with all the starting you are doing.

One thing to check is the fluid level in the battery. They do need to be checked and filled periodically. I changed my KLR out to a sealed Gel type.

 

[mhiscox]

If you think you might have problems, you probably want to have a VRLA (valve-regulated lead-acid) battery, which for all practical moto purposes means a sealed AGM (absorbed glass mat) battery. A flooded cell battery can only be brought back from fully discharged a few times (and sometimes not at all) whereas the AGM will recover from dozens of complete discharges. And an AGM will also hold a charge better during periods of non-use. When you add in the fact that they can't spill and don't need routine maintenance of the electrolyte level, there are strong reasons to go this way.

The drawback of the AGM is the cost, probably double or better the price of the equivalent flooded cell unit. But the advantages will probably make it pay. I have them in my bikes mostly because they sit for long periods during the Oregon winter and it kills the flooded batteries. Using an AGM is easier than messing with Battery Tenders to keep them alive.

 

[SWbySWesty]

This one died within 2.5 weeks of non-op. I'm not really worried as most riding I do isn't technical requiring brutal hill climbs and such. But the topic seemed pertinent for ADV riders. Now, unfortunately, my battery tender is 100 miles away. A few minutes on the car battery (not running) should resuscitate it, but then I have to ride it. Gosh. Golly. That won't be fun in the warm Santa Barbara evening sun! :bike_rider:

 

[Stumpalump]

You can kill it many times as long as it does not sit discharged. FWIW AGM batteries don't take we'll to sitting discharged more than flooded.

 

[mhiscox]

You can kill it many times as long as it does not sit discharged. FWIW AGM batteries don't take we'll to sitting discharged more than flooded.

Not sure I agree with this, though I perhaps didn't understand the comment. My understanding is a) that the number of cycles available when discharging an AGM battery to 80% is the same as when discharging a flooded cell battery to 50%, and b) the self-discharge rate for an AGM batteries is 1-3% per month, versus 5-15% for flooded cell types. Don't know whether either of these facts relates to your point, though they seem useful for the topic, regardless.

 

[Stumpalump]

Not sure I agree with this, though I perhaps didn't understand the comment. My understanding is a) that the number of cycles available when discharging an AGM battery to 80% is the same as when discharging a flooded cell battery to 50%, and b) the self-discharge rate for an AGM batteries is 1-3% per month, versus 5-15% for flooded cell types. Don't know whether either of these facts relates to your point, though they seem useful for the topic, regardless.

Sorry for the confusion. What I'm saying is that an AGM left discharged will not recover as well as a flooded battery left discharged. The moral is to not let any battery sit for long periods if its discharged. That builds a sulfate layer on the plates. Think of a battery as a sponge for electrons. If a sponge is clogged with mud it won't absorb as much water. A battery clogged with sulfate won't absorb as many electrons. Why is an AGM worse at this? I don't really know but that's the word on the street.

 

[SWbySWesty]

After three weeks of sitting, I cranked with no dice. The battery sat dead for four days. Hooked it to a car battery for 30 seconds and it fired right up. Should be charged now but I think the carb had more to do with it than than the battery now.