Battery troubles

I purchased a a standard open cell, lead acid new battery about 4-5 months ago from Advanced Auto for my '84 VF500 and I've been having some trouble lately. It started when the bike wouldn't start right up a few cold mornings, and after a few cranks, the battery was completely out of power. I bump started the bike, and it started up fine after a 10-15 minute ride. This has progressively worsened over the last few weeks so I charged it using a trickle charger at Advanced auto and it took at full charge and the bike started right up the first time. I ran the bike for just 30 seconds or so and decided to get some voltage readings.

After turning the bike off, the voltage across the battery read ~12.5 volts, and then ~11.8v with the ignition on. Then I started the bike to do a load test, and the voltage briefly dropped to ~9v and the bike started up ok. Then I decided to test it once more. The voltage dropped to ~7v and did not start the bike, then a few more cranks and it dropped to ~5v and then the battery completely died out and wouldn't turn over the engine at all.

Does this mean my battery is dead? After only 4-5 months, or could it be something else on the bike is screwy? If the battery takes a full charge, can it still be bad? The fluid levels are all within the required limits. Any help is appreciated!

 

So you're suggesting it is something to do with my charging system... If this is the case, does it make sense that the battery died after only two starts?

 

You omitted the most important test: what is the voltage across the battery terminals while engine is turning about 5000 rpms ?? That determines whether your battery is being recharged.........or not. Anything between 13.5-14.5 volts is acceptable.

 

I tested the voltage across the battery today while running and it was at least 13.5v around 5000rpm and got up to 14 as I revved it higher. So it seems that the charging system is working well. I'm guessing this means I do indeed need a new battery.

Is there any reason my almost new battery is worthless now? When buying a new battery, should I buy a different one, or was this just a fluke and I can buy the same one again (link to it below).

Advance Auto: Autocraft 12-Volt Powersport Battery, 165 CCA

 

#1 you stated you did a trickle charge at advance auto. Sounds like you don't have your own charger. Get yourself a charger/ maintainer. Deltran Battery Tender or the like.

#2 a load test is a direct short! If you also did this at advance auto it was probably an automotive type tester which are usually about 100 amps. This is way too big for your 14 amp battery. Each time you do a load test it puts A BIG drain on the battery. This explains the 2 volt drop in voltage each time you did the the load test. There is probably nothing wrong with you battery other than performing heavy draining load tests.

#3 fully charge the battery with the proper charger. Test the voltage with ignition off after the battery sits for about 1/2 hr. Should be in the 12 volt range. Usually in a wet style battery 12.3 to 12.9 volts. As squirrelman said, now test the voltage whie running. It should now be above 13v and not more then 14.5v.

I think if you get it fully charged and test in this manner you will find your battery is OK.

As I have said many times before go to www.yuasabatteries.com to learn everything you ever wanted to know about the care of motorcycle batteries.

From the home page click on the Technical Manual

 

Sure sounds like a bad battery to me. Get a name brand gel battery, troubles will be over.

 

I've purchased a battery for the Sea Doo before and had it last just past the six Month warranty
Period. Bought it at Battery Mart. My thought was that buying at a battery specialty place would get me a better battery,,,,,oops! I think there's a reason a lot of these places only have a six month warranty.
John

 

Could be a bad cell or cells that went south. Having a motorcycle specific battery tender that does temperature compensation along with a storage reset goes a long way to maintaining a healthy battery.

 

Anyone has/had any issues with the battery dying within 2-3 weeks max. As long as i ride the bike the battery is working fine and shows no signs of dying. It's when i don't ride the bike for 2-3 weeks max that's when i have the problem. The battery doesn't die completely as i do get lights and everything but it does not have enough power to start the engine. Has anyone faced similar issue?

 

Is your battery old (five years or more)?
Measure the battery voltage, 12.0V is discharged, 12.8V is fully charged (lead/acid). Measure the voltage at least 1/2 hour after running the engine/charging the battery.
Measure the battery voltage when the engine is running, should be 14.0 - 14.8V @ 5000 rpm.

Your problem could be a current leak, measure the current as described at the picture below (ignition off). The manual for my 5th gen says maximum 1.2mA (milliamps) current leakage. Guess it's quite the same at your 6th gen.

 

Good suggestions above. You can test for current leakage as quattro sez or just detach one of the battery terminals when you're not riding.

 

Hi and thanks for the info.

The battery is not that old, maximum 1.5years, i did the test and the leakage is around 1.8mA. My bike is a 2002 and the manual says the maximum leakage should be 2.5mA max so i guess i am within the normal range. Also the battery was around 12.3V without riding it for a day and when the engine is running at 5000rpm it is 14.8V so again within the range.

I got the service manual and the only thing that i was unable to test was the current leakage when disconnecting the regulator/rectifier, the plug seemed to hard to remove to measure so i figured i would try sometime later or have the garage do it. I also checked the alternator charging coil and it's resistance was 0.7-0.8 Ohm, manual says it should be 0.1 - 1 Ohm so it's ok.

One thing i read through the manual, when not riding frequently the battery needs to be charged every two weeks, I found it a bit to much. Some friends don't use their bike sometimes for more than a month and the battery doesn't give them any problem to start!

Any other ideas?

Thanks

C.

 

During the constant dis-charge/charge cycles of normal use, sediment builds up on the bottom of each cell and eventually will short out cell. Read up on how lead/acid batteries work, if you can find another battery to try for a couple weeks, then you will know. A fully charged battery should be 13.2vdc, 2.6 per cell. the 14.8 is the output of the R/R, not any indication of condition of battery. You can always take it to a store or shop that has a proper battery tester, that puts it under load. I know NAPA does.

 

I charge my MC batteries minimum once a month during the winter, and store them in a cool place when not in use (winter time). A lead / acid battery's worst enemy is to be stored in a discharged condition, they will then build up sulfate on the lead plates. When charging, the sulfate will build up in the bottom of the cells and short them, as Allyance says, but I do not agree regarding what he says about 13.2V for a fully charged battery. Each cell will have 2.13V when fully charged (density 1.27-1.30) @ 20 degrees celsius. This means a fully charged battery will measure 12.8V max.

nmeeker, try to fully charge your battery, max charging voltage 14.5V and max 4A charging current. If it does not help, buy a new battery and give it a full charge before use.

Sorry if my choice of words or grammar is bad, this is not my spoken language