Battery Voltage test ?

[Nomad2day]

Seeing how my speedometer died last week and following a few others with the same problem going on I decided to test the battery just to see what it is doing at the moment. My bike is a 2007 EFI Bulldog. Bike always cranks

I used the search function to satisfy my the "its been discussed many times before" but you can shift through numerous threads and not get a straight answer, just I replaced the battery and all was good then or the EHC draws 1.5 milliamps a day or your battery will be dead if not ridden in two weeks and if the EHC does not get enough voltage on boot up it will do funny things. The manual says the battery needs to have 12.8 vdc.

I used a fluke meter to take the readings. I placed it on min/max to see what happens when the load it put on it cranking.
My battery has always been on a Battery Minder Plus.

Key Off = 13:10
Key On = 12:50
Run On Fuel Pump Running = 12:40
Press Start = 6:16 at it's lowest reading
Running = 13:90

Is the battery good or Bad?
What should a battery show in the above scenario?
Thanks as always in advance.....
Neil

 

[bdmridgeback]

6.16 volts looks like the battery may be a tad weak. Shouldn't drop that low. Also after I talked to a few shops and some different manufacturers, I found that the 270 cca battery is not quite strong enough for our starters that are drawing more or equivelent of a 2.0kw starter and almost that of a 2.2kw starter!!! That said, the starter really needs a 300+ cca battery.

I bought the Big Boar 350cca battery and it spins my bike over like it never has before.

 

[Raywood]

Neil, using BD flowchart I found the following;

battery voltage - 12.8 min
battery draw - carb 1.4mA, EFI 2.4mA
voltage (running) 13.8 min 14.8 max
stator output - @1000rpm 16-20 volts
starter - pull green wire. measure voltage for wire to ground. Common is 8 volts (note if less refer to starter selenoid chart)
MAP - unplug MAP sensor with key on and measure across terminal A (ground) and c (power). Must be 5 volts. Don't know if this is your fuel pump check you did.
For speedometer it says to verify power to speedo. If no power inspect red wire from EHC for short. If power to speedo inspect wire leading to speedo sensor for grounds, if no grounds replace sensor.

And there is a lot more but this should help you a bit. If you don't have the 12.8 volts at startup and you have a freshly charged battery is says you may have a bad cell.

Seeing how my speedometer died last week and following a few others with the same problem going on I decided to test the battery just to see what it is doing at the moment. My bike is a 2007 EFI Bulldog. Bike always cranks

I used the search function to satisfy my the "its been discussed many times before" but you can shift through numerous threads and not get a straight answer, just I replaced the battery and all was good then or the EHC draws 1.5 milliamps a day or your battery will be dead if not ridden in two weeks and if the EHC does not get enough voltage on boot up it will do funny things. The manual says the battery needs to have 12.8 vdc.

I used a fluke meter to take the readings. I placed it on min/max to see what happens when the load it put on it cranking.
My battery has always been on a Battery Minder Plus.

Key Off = 13:10
Key On = 12:50
Run On Fuel Pump Running = 12:40
Press Start = 6:16 at it's lowest reading
Running = 13:90

Is the battery good or Bad?
What should a battery show in the above scenario?
Thanks as always in advance.....
Neil

 

[Ratman]

Neil...

The others that have already posted have forgotten more than I know about these bikes. However...FYI, about 2 months ago my '07 mastiff (non EFI) would crank fine at home as it was on battery tender. If I turned it off a time or two while away it would crank noticeably harder. Left me on the side of the road when speedo started acting up and I made the mistake of pulling over and shutting off. I checked the battery and it read bad. Put a new interstate in. Did the same thing again about getting weaker to start while away on ride. Took to dealer-they said voltage regulater was bad. Replaced VR, and it still would get weaker while off battery tender on ride. Found out then that the NEW 1 week old battery had a bad cell in it. First time I had been stranded roadside in almost 35 years. How humbling...and I think I learned about 3 new words while standing there! If your speedo gets wacky or just stops...you had better have your cell phone with you.

 

[Nomad2day]

Neil, using BD flowchart I found the following;

battery voltage - 12.8 min
battery draw - carb 1.4mA, EFI 2.4mA
voltage (running) 13.8 min 14.8 max
stator output - @1000rpm 16-20 volts
starter - pull green wire. measure voltage for wire to ground. Common is 8 volts (note if less refer to starter selenoid chart)
MAP - unplug MAP sensor with key on and measure across terminal A (ground) and c (power). Must be 5 volts. Don't know if this is your fuel pump check you did.
For speedometer it says to verify power to speedo. If no power inspect red wire from EHC for short. If power to speedo inspect wire leading to speedo sensor for grounds, if no grounds replace sensor.

And there is a lot more but this should help you a bit. If you don't have the 12.8 volts at startup and you have a freshly charged battery is says you may have a bad cell.

Thanks Raywood,
I have that flowchart as well.
battery voltage - 12.8 min...This is under a load test which I need to take the battery somewhere to verify this. Mine is over this voltage without anything running.
battery draw - carb 1.4mA, EFI 2.4mA Have not checked this
voltage (running) 13.8 min 14.8 max My idle voltage is 13.8 to 14.0. Not really too much higher even if revving the motor.
stator output - @1000rpm 16-20 volts..Ray, if your output is this, it shows the voltage regular to be bad. Mine reads higher than this so it leads you to ohm out stuff.
Ratman...The voltage regulator checked out in all the resistance test...
In the end it says to replace the rotor/stator if the voltage stays low due to all the resistance readings being good, but the voltage is above 13.8 or at it which is the lower limit.

I guess I am back to load testing the battery anyway to get a answer on that.
For speedometer it says to verify power to speedo. If no power inspect red wire from EHC for short. If power to speedo inspect wire leading to speedo sensor for grounds, if no grounds replace sensor.
In the software it showed the voltage to be good and I checked the connections so I emailed Nelson for a speedo pick up Friday morning I think.

My concern was on the battery here due to the voltage dropping continuously when I turned the key on and hit the run on switch which took the voltage below the 12.8 threshold.
When I did the test for the circuit breaker checking voltage on both sides all was good. When I disconnected the B+ wire from the breaker and disconnected the stator plug to take readings and check the output, I went back and did a continuity test on the circuit breaker and it failed on one side as open. What???Pushed the plunger in a few times and hooked everything back up to it and it was working again. The plungers stay out somewhat which I guess is normal. My 2 relays for fuel pump and horn had a bunch or corrosion on the pins si I cleaned them and coated everything with dielectric grease and I plugged them back in.
I will play some more tomorrow but might pull the battery out and get a new one at Harley anyway...
Neil

 

[Billy Big Dog]

With what I see you have an AMp issue. Alot of batteries especially left on a tender will read ok Volts but the CCA are not there. I remove my battety in the winter. Don't know if this is bad or not but I spend less on batteries over the years on all my toys.

 

[Raywood]

Hope it's just as simple as a new battery.

Thanks Raywood,
I have that flowchart as well.
battery voltage - 12.8 min...This is under a load test which I need to take the battery somewhere to verify this. Mine is over this voltage without anything running.
battery draw - carb 1.4mA, EFI 2.4mA Have not checked this
voltage (running) 13.8 min 14.8 max My idle voltage is 13.8 to 14.0. Not really too much higher even if revving the motor.
stator output - @1000rpm 16-20 volts..Ray, if your output is this, it shows the voltage regular to be bad. Mine reads higher than this so it leads you to ohm out stuff.
Ratman...The voltage regulator checked out in all the resistance test...
In the end it says to replace the rotor/stator if the voltage stays low due to all the resistance readings being good, but the voltage is above 13.8 or at it which is the lower limit.

I guess I am back to load testing the battery anyway to get a answer on that.
For speedometer it says to verify power to speedo. If no power inspect red wire from EHC for short. If power to speedo inspect wire leading to speedo sensor for grounds, if no grounds replace sensor.
In the software it showed the voltage to be good and I checked the connections so I emailed Nelson for a speedo pick up Friday morning I think.

My concern was on the battery here due to the voltage dropping continuously when I turned the key on and hit the run on switch which took the voltage below the 12.8 threshold.
When I did the test for the circuit breaker checking voltage on both sides all was good. When I disconnected the B+ wire from the breaker and disconnected the stator plug to take readings and check the output, I went back and did a continuity test on the circuit breaker and it failed on one side as open. What???Pushed the plunger in a few times and hooked everything back up to it and it was working again. The plungers stay out somewhat which I guess is normal. My 2 relays for fuel pump and horn had a bunch or corrosion on the pins si I cleaned them and coated everything with dielectric grease and I plugged them back in.
I will play some more tomorrow but might pull the battery out and get a new one at Harley anyway...
Neil

 

[Nomad2day]

Raywood,
Put everything back together last night after performing all the meter readings on the stator,voltage regulator and circuit breakers.
Get on the sled this morning at 5:30am to go to work and the dang speedometer is working again....
I Know what all I put my hands on but do not know what changed.
I also had a couple of leds on the speedo face flickering about the 110mph area that are stable now too...
Go figure..

Stopped at the Harley shop after work and inquired on a battery for a soft tail.
All of the batteries are 350cca and quoted me a $124 bill.
Neil

 

[Raywood]

Raywood,
Put everything back together last night after performing all the meter readings on the stator,voltage regulator and circuit breakers.
Get on the sled this morning at 5:30am to go to work and the dang speedometer is working again....
I Know what all I put my hands on but do not know what changed.
I also had a couple of leds on the speedo face flickering about the 110mph area that are stable now too...
Go figure..

Stopped at the Harley shop after work and inquired on a battery for a soft tail.
All of the batteries are 350cca and quoted me a $124 bill.
Neil

Another issue with the small gauge wires. Glad it running properly again for you. Could have just been a simple connection on about anything.

:2thumbs: