Another battery question. I am just confused

[posplayr]

that sounds awfully similar to another " immediate, in-situ operational test".

Does it start the bike?


....Many times the directions that come with a new batterywill tell you to let the battery rest.... surface charge does not seem to be the same as self-discharge

http://www.smartgauge.co.uk/surf_chg.html

http://www.batteryeducation.com/2012/10/battery-self-discharge-rates.html

A bike start is a poor test of a battery. Many things other than the battery can keep the bike from running. If the lights are on, and your ignition coils are OK, you have 10 amps of load. And no the starter is not a good test because you don't know if the battery is being pulled down from a draggy battery. Who knows what the load is for every different motor? You think all starters pull the same current regardless if it is a GS400 or a GS1166 with 10.25 CR?
How does your mketer react to the bouncing current draw from the starter and are you going to disconnect the coils so you can run the stater to steady state? There are all kinds of variables you are introducing into the mix.

Self-discharge and surface charge are two distinctly different things but both manifest themselves as voltages.

So when your voltage drops after taking it off the charger, is it the elimination of surface charge and how much of it is self-discharge?

To be clear surface charge represents a state of the battery where it exhibits considerably larger internal impedance. For example, when you first pull the battery off the charger it is probably above 13V. But once you pull a small amount of current, that so-called surface charge of the battery is removed and the voltage drops to a more normal 12.8V. At that point, you can put a larger load on the battery but per unit of current you are drawing, you won't pull the voltage down as much.

In the scheme of things this is a secondary effect but certainly, one that will corrupt your sell discharge based measurements. The point is that dealing in small current loads does not make the State of charge observable because you are trying to infer SOC from small voltage changes affected by secondary effects.

You put a 10 amps load on the battery and there effects are irrelevant and you get an immediate result.

[Gorminrider]

and, Mind you, if you "load test" a doubtful battery away from a handy means to charge it back up, you are hurting the battery. A deeply discharged battery MUST be immediately re-charged, especially the smaller bike batteries...so,again, starting the bike and running it to recharge is the thing wanted..... I think I'll stick with the voltage test as a rule of thumb.

So when your voltage drops after taking it off the charger, is it the elimination of surface charge and how much of it is self-discharge?

very little is "self-discharge".
I've just put the beater bike back on the road. Resting at 12.2 after 3 months and the bike started right up. It's gassing off while I run it round but it's good enough. Starts when I get off and on again. Sure, I can prove it's on its way out and some lump of sulfate is bound to shake loose and short the plates out but meanwhile....

[posplayr]

and, Mind you, if you "load test" a doubtful battery away from a handy means to charge it back up, you are hurting the battery. A deeply discharged battery MUST be immediately re-charged, especially the smaller bike batteries...so,again, starting the bike and running it to recharge is the thing wanted..... I think I'll stick with the voltage test as a rule of thumb.

You distract and deflect. The key on load tests takes less than 2 seconds. As long as it tacks for the needle to move and register a voltage. A bike can run on battery alone for over an hour and there is nothing precluding from riding the bike for hours after the test as long as you have gas.

I have little doubt you will keep doing what you do. I'm just aprizing anybody else that it makes little sense when the key on test is objectively so much superior.

[Steve]

... the key on test is objectively so much superior.

And only requires a simple voltmeter as a 'test tool'.

.

[Gorminrider]

I take your point about 2 seconds key on being "trivial" and it's fine to say that "my battery falls to a certain voltage and stays there" indicates that it can do that for awhile. But starting the bike being "a poor test" seems pretty odd to me. It's what I want it to do and it's what the battery is designed for.

As to key-on test, "and "internal resistance" etc etc etc etc, doesn't it suppose all Suzukis have equal key-on loads? I suppose I can figure out a sum of 10 amps if I don't have an LED headlamp but You don't exactly say what a reading of your method is going to tell anyone. Judging by your reference to your "quick test", nobody is going to "pass" the test as "normal" unless they have a brand new battery....or should I expect a 1/2 volt drop?


A real load test is done out of the bike for this reason-separating it from the bike's problems. ....as to the "only way to test the battery" well... I mentioned a hydrometer. I don't agree that that's "deflection and distraction". It tests each cell and is crucial to gauging battery health whether it's a new or old battery...(the point of my anecdote) I'll certainly miss them as the no-maintenance batteries take over because getting a gaurantee honored is going to be less... "user accessible"?

But there's tons of info on "battery-wanking" online.

http://batteryuniversity.com/learn/article/bu_914_battery_test_summary_table

It isn't a super-duper test but a simple voltage test on a battery on the bench or in the bike before you turn the key can be done on almost any battery. There's a simple tablesomewhere but hey, IMO 12.5 and up is pretty good, 12.2 and below is getting iffy. Easy.
sure, if I have it right? you can turn the key and take 1/2 a volt off that. So what?

Combining whichever simple test with trying to start the bike a few times and running around to charge it up to do it again, it's what I think most of us want to know- Will it start the bike and "gee-should-I-think-seriously-of-replacing-the-battery-before-buying-bling".

[posplayr]

I take your point about 2 seconds key on being "trivial" and it's fine to say that "my battery falls to a certain voltage and stays there" indicates that it can do that for awhile. But starting the bike being "a poor test" seems pretty odd to me. It's what I want it to do and it's what the battery is designed for.

As to key-on test, "and "internal resistance" etc etc etc etc, doesn't it suppose all Suzukis have equal key-on loads? I suppose I can figure out a sum of 10 amps if I don't have an LED headlamp but You don't exactly say what a reading of your method is going to tell anyone. Judging by your reference to your "quick test", nobody is going to "pass" the test as "normal" unless they have a brand new battery....or should I expect a 1/2 volt drop?


A real load test is done out of the bike for this reason-separating it from the bike's problems. ....as to the "only way to test the battery" well... I mentioned a hydrometer. I don't agree that that's "deflection and distraction". It tests each cell and is crucial to gauging battery health whether it's a new or old battery...(the point of my anecdote) I'll certainly miss them as the no-maintenance batteries take over because getting a gaurantee honored is going to be less... "user accessible"?

But there's tons of info on "battery-wanking" online.

http://batteryuniversity.com/learn/article/bu_914_battery_test_summary_table

It isn't a super-duper test but a simple voltage test on a battery on the bench or in the bike before you turn the key can be done on almost any battery. There's a simple tablesomewhere but hey, IMO 12.5 and up is pretty good, 12.2 and below is getting iffy. Easy.
sure, if I have it right? you can turn the key and take 1/2 a volt off that. So what?

Combining whichever simple test with trying to start the bike a few times and running around to charge it up to do it again, it's what I think most of us want to know- Will it start the bike and "gee-should-I-think-seriously-of-replacing-the-battery-before-buying-bling".

So you know, I have a BSEE and MSECE with over 30 years experience. I worked under contract directly for US Army customers responsible for maintaining all the large tactical vehicles. As part of our team analysis, the conclusion of any diagnostic testing for the charging systems was that an integrated test , observing charging current and voltage under different conditions was the simplest way to diagnose that class of problems. Our objective was to identify the cheapest and most reliable methods for automatic diagnostics.

How does this apply to the GS Charging system? Well it is very similar; the same three components Battery, Charging, Load. The biggest difference with a GS is 1/2 the people don't seem to even have a voltmeter, don't have a clue about electricity and much less about diagnostics. A complex test or a test with many possible outcomes (Prateo Outcomes; the probability of all possible outcomes) is not going to be easy for this group of people to implement.

Yes the Quick test is based on a standard load. All licensed UJM's with non-EFI are going to have very similar loads due to DoT regulations for headlamps and tail lights. All coils are 3-4 ohms. EFI will bring in a large load fro a fuel pump. That all said, all you have to do is adjust the numbers up or down oin proportion to the actual load current to adjust the expected voltage readings.

If you expect a 1V drop for 10 amps, and you install LEDs and only have a 5 amp load then expect only 0.5V drop. The drop should be in direct proportion to the load.

Getting back to possible outcomes, the reason why starting the bike is not a good test for a battery is because it is not quantitative. Measuring a voltage even despite a few caveats is quantitative. It is therefore much easier to diagnose a members GS just from those readings alone without hearing the bike.

In addition, there are many possibilities like the solenoid just clicks, the solenoid is not grounded, the starter is dragging, the carbs are fouled, the battery connections are loose. With the Quick test, Key ON , anybody can see if their headlamp and tail lights are on. and hopefully, measure the 12V at the battery and see the small changes as you progress through the rest of the test.

Recall the Quick test is a quick integrated evaluation to establish a baseline to direct further testing. By the historical record, it is very effective at effectively supporting charging system diagnostics. The original stator pages were simply too complex for many people. The primary characteristics of the original stator tests were that some tests were unnecessary or had indeterminate outcomes which only increased the complicated of further testing.

[Boriqua]

Since it may be germane

So after I went and had the load test done at the local autoparts I brought the battery home and topped up all the cells and put it on a battery tender overnight.

When I was up in the morning the light was green and I removed the tender and let it off gas about 3 hours. I put the meter to it and it read 12.75

Two days later I went for a ride and before I left the battery read 12.57. This is cold and with no key.

Got home and checked the battery the next day and 12.38 ... which is where I started. I have since been out about 5 times started and shut down about 15 times and covered a little over 200 miles and checked this morning before I went out

12.38.

So .. I think I have to resign myself to the fact that the battery is just not going to do better than 12.38 for the time being.

[posplayr]

Since it may be germane

So after I went and had the load test done at the local autoparts I brought the battery home and topped up all the cells and put it on a battery tender overnight.

When I was up in the morning the light was green and I removed the tender and let it off gas about 3 hours. I put the meter to it and it read 12.75

Two days later I went for a ride and before I left the battery read 12.57. This is cold and with no key.

Got home and checked the battery the next day and 12.38 ... which is where I started. I have since been out about 5 times started and shut down about 15 times and covered a little over 200 miles and checked this morning before I went out

12.38.

So .. I think I have to resign myself to the fact that the battery is just not going to do better than 12.38 for the time being.

Not nearly as germane as to what happens when you turn the key on.

[Boriqua]

I just came in from a 10 mile ride about an hour ago. When I left it was 12.38. I checked just now and it was 12.49. I turned the key on for 10 seconds and I got 11.84. After about 15 seconds it was at about 11.70

After rereading the charge test I should have gone from 12.50/12.49 to no less than 12.00 on a healthy battery ... Right?

[posplayr]

I just came in from a 10 mile ride about an hour ago. When I left it was 12.38. I checked just now and it was 12.49. I turned the key on for 10 seconds and I got 11.84. After about 15 seconds it was at about 11.70

That is just passable. As long as it cranks fast enough to start without kicking back the starter you should be OK for a while.

The fact that the voltage did not drop much further, implies that it is only the one cell that is compromised but not so much that you can't run it. To a certain extent, my comments are also simply reflecting your experience with the battery.

[Boriqua]

Thanks for the input !! I was happy to see the battery is indeed charging since I left at 12.38 and came back to 12.50. I suppose that if I checked 24 hours after a ride it would have dropped back to 12.38.

Again ... cant fault the no name battery as I abused it. I will ride it out a couple more months and keep checking voltage and then pick up a new one. That will have given me almost 2 yrs and I can live with it.