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battery voltage 2007 R1200RT

norvillnh88

Mick-F
What is considered adequate voltage across the battery terminals when the motor is being cranked over? The bike is a 2007 RT, bought new in March 2008, 26K miles on it original battery. I have no problem starting it now.
Thanks Mick
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I don't know if my '05 GS experience holds for the RT, but if it does the voltage will drop a LOT for a short period at startup.

The following is a plot of startup voltage as sampled using the GS-911 on an OK if not 100% charged battery. The X axis is milliseconds. When the button was hit the voltage dropped to just above 8 volts... probably until the starter actually started turning when the voltage returned to about 11.75v. Once the alternator kicked in the voltage varied between 14 and 14.5 volts.

battery.jpg
 
Fascinating info, Marc!

I know very little about the GS-911, just some of the info in the DIYs on its use. Did the GS-911 generate the data and was it captured for you to chart in Excel?

Thanks,
 
The GS-911 software that runs on your PC can capture the output of a bunch of sensors save the data in a CSV file. I don't know of the bluetooth phone version can do the same. I used something similar to Excel to read the CSV file and generate the plot. I forget exactly what.

Just yesterday I used the GS-911 to verify the operation of my clutch switch and discovered that it wasn't operating until the clutch lever was pulled almost all the way to the bar. Link.
 
Yuasa says 12.6 to 12.8 V, so they think yours is too high. :jester

For a flooded lead acid battery...maybe.

I can't control what the rest voltage of my battery is after it has been fully charged. That is the voltage a day, a week and two weeks after my charger has been disconnected. It decreases to 12.8V in the third week. :p
 
For a flooded lead acid battery...maybe.

I can't control what the rest voltage of my battery is after it has been fully charged. That is the voltage a day, a week and two weeks after my charger has been disconnected. It decreases to 12.8V in the third week. :p

True, but what charger is being used has a bearing on what that charger considers to be "fully charged".
 
True, but what charger is being used has a bearing on what that charger considers to be "fully charged".

True, but then it would either overcharge, undercharge or charge a battery just right.

The rest voltage has nothing to do with the charger other than charging the battery fully or not, in the latter case, it might be a bit lower.
 
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