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My darmah battery is losing water over 100 miles or so. The battery is brand new. Usually that points to a bad voltage regulator. I charged the bettery and ran at 3k rpm. It puts out 14.7-15 volts. I believe thats too much., and my regulator is bad. Correct?

I would think. Check all terminal connections while you are at it, clean and seal with dielectric grease. Pick up a newq regulator and AGM battery . Aso I advise al bevel owners to add an additional ground wire from the neg battery to the engine, typically to the clutch cable adjuster where it threads into the top of the engine case.

The stock darmah regulator should stop charging the battery at between 14.0 and 14.2 Volts. If the regulator breaks, it will almost always pass on the full charging current. The voltmeter (red plastic encased box near fuses) that drives the GEN light should cause the light to come on when the battery tension reaches 15.7 Volts.

One thing to check is that your regultor body is properly earthed. If it is isn't, it is probably stuffed. That's often what causes them to fail. As Steve alludes, dielectric grease is often cheap insurance against that particular scenario.

Kev

Thanks guys. The extra ground is on my short list of things to do. I did check to see if the regulator body was grounded and it is. As far as my gen light, most of my indicator lights on the dash gave up the ghost long ago. ....
What other bikes used this regulator? Late bevels, pantah, paso, and what else? Mike

It seems I fried the regulator too. Today just warming up the engine after one minute I got the red GEN light on and now it stay on at every rpm.
The regulator was correctly grounded and I have added just today the ground between the negative pole of the battery and the clutch cable adjuster.
What's the correct flux chart to find if the problem is the regulator, the alternator or the connections? Is there a way to test the regulator with a multimeter?
For mizike77
the 0759.46.750 regulator fits the bevel twins and the Pantahs.
It's very easy and very cheap to repair the Darmah dash lights changing the old burnt lamp with a led, I did it for all my warning lights. You have just to add a 470 Ohm resistor on the positive pole of the LED and to remember that you have to respect polarity (connect the positive to the side you put the resistor). Just a ten minutes work and few dollars work and I love to have my warning lights working. I'll not have found the problem today without it.

Just checked my voltmeter readings.
Before to test I fully charged the battery with an external charger.
- with engine off 13.40
- at idle 13.68
- giving throttle I read a drop around 2000 rpm with reading 12.50 and after that it returns to 13.50
- at 3000 and 4000 rpm same reading about 13.52, but quite variable with drops to 13.20 and peaks to 13.70
- turning headlamp on the reading increases to 15.30
Just before to ignite the engine, with battery fully charged, turning the key to ON position I got the Gen light on for a few second and than off (13.40 reading)
Just after ignition and during all the readings the gen light was on.
Where do you suppose may be the fault?

I understand that these systems never were the best,If that was mine I would not worry too much , but would consider fitting an additional clipper type diode to trim off the voltage,possibly a zener with a heat sink. In the event of regulator failure it should protect the battery.But then i never did follow the rules!!.

Just swapped my regulator out for a known good one off my GTS. Im still getting high readings of 14.2-14.7 at 3k rpm. And it drops to 13 ish volts with the headlight on. Any other ideas?

i have a brand new reg and battery on my ssd, it is wired directly to battery rather than going through the 30yr old harness, as i have moved it to behind the rear carb on the old air box mounts and i run a volt meter as well(hooked directly to the battery) and i constantly have those readings,one thing i have not done is measure the current going to the battery though.

Many reasons for erratic battery voltage on Ducks, One thing worth checking is that the signal voltage to the regulator via the ignition switch is good, Ducati used a poor system of running all the electrical load through the ignition switch and back to the fuse box and regulator, any high resistance joints or dicky switches causes the reg output to go high.
Be wary of using Digital multimeters on the bike with the engine running some give very inaccurate readings due to electrical "noise" mainly from the ignition. Some meters are better screened than others and work OK but an old fashioned analoge meter should be immune from noise.