Voltage drop off

[easy riders]

Hi guys,

I have and issue with my dog.
when I start the engine and is idle, I measure 14.5V, but when I give gas it drop below 10V.
is these normal?

thx in advanced,
errol

 

[BigDogBro1]

Around 12v at idle and near 14v at 2000rpm seems more normal.

After fully charging your battery...disconnect the charger for a few hours then measure voltage across the terminals and it should read 12.6 to 12.8 if the battery is in good condition. Could be the regulator or stator.

SEARCH for voltage regulator and stator in the forum, there's many posts with good info for things to check.

Look under technical how-to's as well.

I Found this:
Yes, Holding your meter leads to your battery posts you should have at least 13.5 and no more than 14.6 @ 3000 RPM. You said you did check output on your stator, 1k rpm, 2krpm and 3k rpm? Also make sure you have no opens or grounds using your ohms setting, check continuity threw the output wire of your stator. Check both wires to make sure there is no open or continuity to ground.
If the stator passes all tests then, yes most likely it is the Voltage Regulator. You said you are getting the same reading on both sides of your circuit breaker?

 

[easy riders]

at idle it shows 14.5V.
the battery measure 12.8V
I already burn 2 VR, do you think is the stator?

 

[bdmridgeback]

Hey Errol....

The voltage at idle should be 12 volt and as you rev it up it should go up to a peak of 14.4 max.

If it is dropping then I am sure the stator is the issue.

Make sure to post that you have a mismatched Accel VR hooked to the stock stator just so you can get some accurate feedback.


Testing the Stator.

Let me preface this be saying you need to be extremely careful when performing the AC voltage check. It should not kill you but it is sure to scare the shit out of you of you let the probes touch each other or ground and will probably damage your meter and probes.

To test the stator start with a resistance test.

1. Remove the VR plug from the stator.

2. Measure the resistance across both pins of the stator plug. The resistance should be 0.5ohms or less, usually it is zero on most meters. Do not forget to subtract the resistance of your meter leads. If it is an open circuit the stator windings are damaged and the stator needs to be replaced.

3. Measure resistance from Pin 1 (either Pin) to ground and then from Pin 2 to ground. It should be an open circuit in both cases. If it is not then that means the windings are shorted to ground and the stator is bad, the plug may be damage or the rotor has interfered with the wires. Remove outer primary and rotor to inspect stator.

4. If stator passes resistance check you can check the output voltage. Again BE CAREFUL!! remove the vR/Stator plug. Start the bike, measure AC voltage across the to stator pins. At idle you will have around 15-20VAC, the voltage will increase as the RPM is increased. The voltage can go up to about 60VAC or more at high RPM. Have a buddy help you run the throttle, keep you eyes on the probes and do not let them touch each other or ground. If you see voltage as indicated below the stator is functioning.

Don't forget to plug your VR back into the stator plug when your testing is done.

 

[RubWhore]

If it passes all Jakes suggestions pull the primary and make sure your magnets haint slid on the rotor

 

[easy riders]

test 2: 1.8 ohm
test3: both open
test4: between 21 and 23 V.

I have another VR hook up to the stock stator that I get from carlsspeedshop it ACCEL VR but it is not hook up

 

[easy riders]

when I rev it go up to 75 V

 

[bdmridgeback]

The VR that is installed now is the 3 phase unit that you bought?
If so, a 3 phase VR will not work with the stock charging system.

The Accel unit may work, but I would need a part number so I could look it up and see if it is compatible with the stock stator. If you have a Accel Stator as well, change them both so that they are a matching pair.

 

[easy riders]

The VR has two wires go to the stator one wire go to the + of the battery and a ground wire go to the - of the battery.

the part number for the Accel is 201122C

 

[easy riders]

Jake,

I want to buy the Compu Fire 40 amp 3 phase charging system.
do you now exactly which one I need to buy and where for BDM pitbull 2007
do you check if the Accel VR ( P/N 201122-C) can be used with the stock VR



thx,

errol

 

[RubWhore]

Jake,

I want to buy the Compu Fire 40 amp 3 phase charging system.
do you now exactly which one I need to buy and where for BDM pitbull 2007
do you check if the Accel VR ( P/N 201122-C) can be used with the stock VR



thx,

errol

You will have no regrets going that route

 

[MisterMister]

My battery registers a constant 14.2 volts at idle or increased rpm. This is with a Drag Specialities VR. Which is my 3rd VR.

 

[easy riders]

Hi,

I connect the Accel Vr to the stock stator and now I get 14.3 V on idle and 14,5 V when Rev.

 

[BadBrad]

Looks like it was the VR after all. Glad you got'er fixed!