Battery testing

[zman]

Maybe someone can tell me if this sounds good/normal. The bike has no problems charging or starting.
Bought the battery second hand from a GL enthusiast that bought it new, ran a year and he started adding lights and accessories and thought he should upgrade the battery...I purchased his 1 year old AGM type and it sat about a year till I finished my project with an occasional 2amp charge but no tender.
What concerns me is I have had to top it off 2 times in the last year, each time it was about 1/2 inch below the fill line..OK..Not sure if this is normal...there are caps on the cell for that reason but dont recall other bikes needing it that often.
Just for wonder I went out after it has sat a week and checked the battery volts..It measured 12.31 then without starting the bike I put the key in ignition on (kill switch engaged)it dropped slowly to 11.60 took about 15 seconds and stabilized.
I do not own a load tester so is there any comparison I can use or any poor mans load test method you know of?
Probably just being paranoid but I want to keep up my battery/charging system up to snuff.
Thanks.

 

[dan filipi]

A simple load test is charge the battery fully then let it sit for an hour not connected to anything.
This lets voltage stabilize.
Connect it to the bike and crank it for 10 seconds with a known accurate volt meter connected.
During cranking, voltage shouldnt drop below 10 volts. After the 10 second crank, volts should come back to at least 12 volts.

 

[Ansimp]

Nice simple test Dan :good: Even high 9s would be ok
Jeff I can't be 100% but all my AGMs are fully sealed to the untrained eye ( the have a gas regulator/vent) and can't be refilled. I am assuming you have a lead acid wet battery (possible calcium or the new silver calcium) which in a high charging voltage system you will be required to top up the battery ( another reason I like the Mofset rr as it has a lower upper voltage setting)

 

[zman]

Thanks Dan, sounds simple enough..What kind of time should it take to get back to 12 Volts?
Tony, yes your right..A typical lead acid Yusa 12 volt..Been shopping batteries and had AGM on my mind.

 

[dan filipi]

It should come back to 12 volts within a couple seconds.

 

[mcgovern61]

Two years on a Yusa lead acid battery that sat? Was it sitting on concrete for the last year? If so, I would not trust it. If not, at best you might get another season out of it, but I wouldn't hold much faith in it (IMHO).

 

[zman]

Gerry, It actually sat A year with every 60 day charges..
Looks like I`ll be OK for now..I followed Dan`s instructions and after 10 seconds it was reading 10.16, I went a few seconds further and it stayed at 10.16, The starter was spinning as fast as it was from the start of the test, didn't slow down any.
I do want to change out the battery and install a Mosfet regulator at some point, I like the idea of better voltage regulation.

 

[Ansimp]

Sound like your battery is good to go Jeff :good:

 

[Steve83]

+1

 

[dan filipi]

Jeff for reference fwiw, my 1 year old Odyssey battery full charge test voltage at 12.8 drops to 10.6 and stays there during cranking the 1200 under compression.
After 10 second crank it jumps right back to 12.6.

 

[mcgovern61]

Sounds like you are good to go Jeff! :moped: