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Battery Tester Recommendation

alegerlotz

Member
I did a search first and found lots of threads about batteries, but nothing about equipment to test them.

Rather than replacing my battery every x months/years because the calendar says its time, or worse yet, waiting until it fails, I'd like to get a tester to help determine when it is actually time to change it based on battery condition. This should save money, resources, and create a bit less toxic waste in the world.

I looked on Amazon there are dozens available. Pretty much all give a voltage they support, most include a CCA range, and some give an amp hour range.

Does anyone have a recommendation on a decent load tester they use for their RT's battery?
 
I purchased this one on Amazon, KONNWEI KW600, many similar ones, I decided based on ratings, the ability to upgrade firmware and option to print results:

https://www.amazon.com/dp/B07QYS4KRM/ref=cm_sw_r_em_api_i_c_pATtEbA6QPE48

Other option was the Topdon BT100, Kirk from N. Illinois BMW Club reviewed this one vs Snap-on in a video he posted, both work similar, Topdon costs much less than Snap-on.

https://youtu.be/AyMTpVxsnhE

At our Auto Shop we used good old VAT-40 machines, big, reliable and old, but we started using these smaller battery testers when they first came out and at that time they were quite expensive, but now you can buy many in the $50-100 range. Small easy and accurate.
 
A multi-meter will do the job and has many other uses as well. The best way to check the health of your battery is to test the battery under a starting load and a multi-meter does this job well.
 
The smaller the battery, the harder it is to predict when it will fail. It would be great to get a baseline reading when the battery is new and replace when you start to see sharp drop off in your measurements. The gold standard battery tester is the Midtronics most auto shops use. If you did decide to buy one of those cheap Chinese versions, I would at least try to compare the results with a shop that has a Midtronics to verify the measurements are similar.
 
Ok, I'll bite. How do you test battery condition with a voltmeter?

Batteries are tested by putting a load across the terminals and seeing what the battery voltage does. The all-in-one testers have software that reads "good-or-bad" on the meter to let you know the state of the battery. But a voltmeter can be used to read the voltage while starting. If the voltage doesn't go below approximately 10v when hitting the start button, the battery would be considered good. If the voltage reading goes well below 10v, then it's likely the battery is bad. This video indicates the "magic" minimum voltage is 9.6v.

<iframe width="560" height="315" src="https://www.youtube.com/embed/tsJUuLu1cw0" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
I disagree.

If the battery voltage drops below ~10 volts while cranking there is something wrong. It could be a bad battery, a bad starter, or even something wrong with the engine putting more load on starter.

If the battery voltage stays above ~10 volts while cranking, it means the battery is adequate for the load. It does not mean the battery is in excellent shape. You can have a 400 CCA battery that spins over a 250 CCA load with no issue, but the battery can still be failing.

I just went through this with my wife's car. Slow cranking battery voltage dropped to about 9 volts while cranking. Battery was seven years old so no great loss if I replaced it. Tossed in a new battery, cranking volts was better, but still under 10 volts, engine spun over faster, but still not right. The car ran fine so no apparent issues with the engine so I tossed in a rebuilt starter. Cranking voltage was 11 volts and it spun the engine over well. I believe the original battery was fine, but with it's age I didn't care. A battery tester would have saved me the $100 for the battery that probably would have lasted another couple years.
 
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You make a good point. Testing in the bike reveals results for several components, as you say, the starter is in the loop. Out of the bike is a cleaner test. I'd say that the first step is to do the in-bike test in your driveway. If the results leave you puzzled, then take the time to get the battery out for additional testing...mine is difficult to remove. I suppose one could just remove the +/- terminals and do the test of battery only while still in the bike. Not everyone has a battery load tester that can be relied on.
 
Kurt, don't get me wrong, the voltmeter and cranking voltage test is the first thing I would do, but it is just an indicator, not an absolute test. I also have a induction amp meter where I can test cranking amps. Funny thing about testing my wife's car, the voltage test failed, but the actual cranking amps draw was low, with the bad starter. That is another reason I went for the battery first. If the cranking amps were high I would have gone to the starter first.
 
I have quite a few ways of checking batteries. After seeing the AE300 in action, I bought one. I am rather impressed with the results and can’t really say how it is doing what it does.

https://www.youtube.com/watch?v=uKBAtfwN_5U

Along with all the battery test equipment I have, most of the chargers I have are of the heavy “transformer” style. In my latest charger purchase, I have found the same “type” of battery information as to the batteries condition.
Again, I don’t know how this “newer” battery testing/charging system is doing what it does but so far so good.
OM
 
A multi-meter will do the job and has many other uses as well. The best way to check the health of your battery is to test the battery under a starting load and a multi-meter does this job well.

That's a good test without spending money on a dedicated load tester...my cheaper method this year seems to park bike outside during a freeze and after gearing up for a ride and climbing aboard, hit the starter...has found two weak batteries recently:laugh:laugh:laugh :banghead
 
That's a good test without spending money on a dedicated load tester...my cheaper method this year seems to park bike outside during a freeze and after gearing up for a ride and climbing aboard, hit the starter...has found two weak batteries recently:laugh:laugh:laugh :banghead

That is the same method I used a few weeks ago. :banghead
 
On all of my bikes I have added a fused, direct-to-battery wire with an SAE connector. I use this for both connecting a battery tender device while the bike is parked in the garage and to provide power to my heated jacket liner and gloves in cooler weather. [The older Gerbings gear used the SAE plug, but newer stuff from Gerbings, Warm & Safe, California Heat, and perhaps others use a coaxial-type plug, thus an adapter is needed].

For a quick check of the battery this direct-to-battery connection can be used. Just touch the black and red probes from the multi-meter to the SAE connector pins and the battery voltage can be measured. It can be a bit tricky to hold the multi-meter probes to the SAE pins while starting the bike (a helper is useful here). When the ignition is turned on and lights are on one can expect to see a voltage drop from this load on the battery; if the battery voltage goes below 10 volts it is likely that there is a problem. When the starter button is engaged the voltage may drop a good bit (it is at this point that I usually fail to keep a good connection between the probes and SAE plug - a helper is useful!!). One should observe the measured voltage quickly increasing to a level near or even above the initial voltage. As the bike is rev'd up a bit the voltage should increase even more, but not exceed 15 volts. The increase is an indication that the bike charging system is working and the voltage regulator should limit the maximum voltage. One might notice a slight brightening of the headlamp when the bike is rev'd up, but this might not be observed in all instances.

For batteries outside the bike I have found a battery load tester to be useful. This device has a voltmeter and a switch for applying a 100 amp load. I usually apply a load for about 10 seconds and observe the voltage upon releasing the switch and dropping the load. I may apply a load for a longer time (about 20 seconds) and again observe the voltage. One will feel the resistor in the load tester heating up. Following is a link to the inexpensive load tester that I use -

https://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

61747_W3.jpg
 
Lee,

A related, question......….where are the "remote" or "external" jump start terminals on our R1200RS's?

It's covered by a red plastic cap.
This picture shows a battery terminal and the red cap covering the remote terminal.
Right side of bike

Battery 1.jpg
 
On all of my bikes I have added a fused, direct-to-battery wire with an SAE connector. I use this for both connecting a battery tender device while the bike is parked in the garage and to provide power to my heated jacket liner and gloves in cooler weather. [The older Gerbings gear used the SAE plug, but newer stuff from Gerbings, Warm & Safe, California Heat, and perhaps others use a coaxial-type plug, thus an adapter is needed].

For a quick check of the battery this direct-to-battery connection can be used. Just touch the black and red probes from the multi-meter to the SAE connector pins and the battery voltage can be measured. It can be a bit tricky to hold the multi-meter probes to the SAE pins while starting the bike (a helper is useful here). When the ignition is turned on and lights are on one can expect to see a voltage drop from this load on the battery; if the battery voltage goes below 10 volts it is likely that there is a problem. When the starter button is engaged the voltage may drop a good bit (it is at this point that I usually fail to keep a good connection between the probes and SAE plug - a helper is useful!!). One should observe the measured voltage quickly increasing to a level near or even above the initial voltage. As the bike is rev'd up a bit the voltage should increase even more, but not exceed 15 volts. The increase is an indication that the bike charging system is working and the voltage regulator should limit the maximum voltage. One might notice a slight brightening of the headlamp when the bike is rev'd up, but this might not be observed in all instances.

For batteries outside the bike I have found a battery load tester to be useful. This device has a voltmeter and a switch for applying a 100 amp load. I usually apply a load for about 10 seconds and observe the voltage upon releasing the switch and dropping the load. I may apply a load for a longer time (about 20 seconds) and again observe the voltage. One will feel the resistor in the load tester heating up. Following is a link to the inexpensive load tester that I use -

https://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

View attachment 77275

For a voltage check, battery tender and others make small voltmeters which plug in to a SAE lead.

Relative to the HF load tester, that's why I asked Lee about the external jump points. A load test should be the best means of evaluating a dead battery, but removing the battery is a PITA on late model (ok, the last several decades) bikes and cars.
 
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My experience is that load testing really needs to be done with a battery totally disconnected.
OM
 
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