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What voltage should I be seeing on my R1200RT battery when it's running

tasslehawf

New member
I suspected that the stator may have lead to the death my battery. I got my new battery in just now and started 'er up and I'm seeing 13.85 volts on the battery terminals. Shouldn't it be higher (like 14.3 or something). What is the work of replacing the stator on the R motor?
 
Your reading sounds good to me. You may get a bit more at higher RPM’s.

OM
 
Potentially unrelated, but on my way to work the bike just died completely. Battery voltage is still good so it's a mystery.
 
Yay!! Electrical gremlins are fun!

What was the history of the battery that you replaced?


You can load test the battery:

"Your local automotive shop is more than able to load test your battery for you. But it's quite easy to do at home. All you need is a digital voltmeter. For any load test to be accurate, the battery must be fully charged. Let's use a motorcycle battery for an example:

Remove the seat and expose the battery in your bike so that you have access to the terminals. Do not disconnect the battery because you will attempt to start the bike.
Hold the prongs of you voltmeter to the correct terminals on the battery.
Now push the start button and watch what the voltage drops to. It doesn't matter if the bike starts or not, what you're looking for is a voltage reading.
A healthy 12 volt motorcycle battery should maintain a range from 9.5 - 10.5 volts under the load for a good 30 seconds straight. If the battery begins to hold and then steadily drops in voltage, there is a problem. If the voltage instantly drops to 0 volts, that is also a problem. We call this the open cell. On a new battery, this can be a result of manufacturing flaws, but it also may be caused by sulfate crystal buildup."

Taken from: https://www.batterystuff.com/blog/how-to-tell-if-your-battery-is-bad.html
 
The old battery I replaced ran perfectly for 2 years and then it was at 4.89 volts with the bike sitting for a week. It ran fine the week before, but sat for a week over the holidays.

The new battery sits about 13.5 - 14.1. I noticed the battery seems to slowly drop as the bike idles.

I noticed these two fault codes related to the battery. The over-voltage one is disturbing:

41704 : KL30 (Battery positive) under voltage
Currently present : NO
Symptom : Signal or value under threshold
Engine warning light (MIL) : NO
Frequency count : 1
Logistic(Healing) count : 39
Fault Code History : Unknown
|
41758 : Battery Positive (KL30) over-voltage
Currently present : NO
Symptom : Signal or value over threshold
Engine warning light (MIL) : NO
Frequency count : 6
Logistic(Healing) count : 40
Fault Code History : Unknown
 
The old battery I replaced ran perfectly for 2 years and then it was at 4.89 volts with the bike sitting for a week. It ran fine the week before, but sat for a week over the holidays.

The new battery sits about 13.5 - 14.1. I noticed the battery seems to slowly drop as the bike idles.

I noticed these two fault codes related to the battery. The over-voltage one is disturbing:

41704 : KL30 (Battery positive) under voltage
Currently present : NO
Symptom : Signal or value under threshold
Engine warning light (MIL) : NO
Frequency count : 1
Logistic(Healing) count : 39
Fault Code History : Unknown
|
41758 : Battery Positive (KL30) over-voltage
Currently present : NO
Symptom : Signal or value over threshold
Engine warning light (MIL) : NO
Frequency count : 6
Logistic(Healing) count : 40
Fault Code History : Unknown
Faults with new battery or faults left over from old battery?
OM
 
I strongly suspect you had a failed (broken) intercell connector - ie battery shot craps - on the old battery. The faults still appear but not related to the new battery. Clear all faults and see, but I suspect the new battery eliminated the problem.
 
Last edited:
I strongly suspect you had a failed (broken) intercell connector - ie battery shot craps - on the old battery. The faults still appear but not related to the new battery. Clear all faualts anad see, but I suspect the new battery eliminated the problem.

Pretty much my thoughts. These complicated bikes with small batteries are easily pushed to the edge.
Clearing the codes is the way to go. One of those “Anti-Gravity” jump packs is starting to sound like a must have.
OM
 
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