Hi all-

I've got a 4-year-old electronic regulator I purchased from Hans Beck. I'm recently getting some odd behavior that I think might be tied to the regulator, but I'm not great at solving electrical issues. Also seems like 4 years is a short life for an electronic reg. Here's the summary:

Ammeter is working correctly
Under light load and low RPM (no lights, or LED tail and/or headlights), ammeter stays centered, as it should (LED load is negligible).
Under light load with increasing RPMs, ammeter shows positive to battery (again, as expected).
Under heavy load (incandescent lights, or horn), ammeter is negative at ALL RPMs (and bulb brightness doesn't increase, which isn't surprising with the ammeter not moving with RPM increasing)

So basically, under a bit of load, dynamo isn't feeding the electrical system, even at high RPMs. What's also odd, I've never noticed this before, but I think I can hear the dynamo make more noise when it's feeding the system. That is, when I increase load and the ammeter drops suddenly, I also hear what basically sounds like the dynamo shutting off.

Any thoughts??? I'm out of my league on this one. I haven't changed anything on the bike, this just started happening intermittently, and now seems permanent. Thanks!

Craig

Hi Craig.

I would suspect that when you are running your system on full load,
The output of the charging system is "Out of the loop",
And this is why you do not see a positive charging in this mode.

I would try to see if the regulator's output is connected to the battery
Like it should, and not passing through the light switch.

In case of an electronic regulator,
It can also overload the regulator's transistors and permanently damage it,
As the energy being built on it does not have anywhere to go.

Good luck,
Noam.

email (option): noam10@gmail.com

In my very limited experience, solid state regulators either work or they don't.

If they burn out, I think the "fail safe" is that charge from the dynamo will not go through to the battery (i.e. if the reverse was true, the battery would boil).

So, I would put a voltmeter across the battery and see if the voltage increases as the revs increase. If the voltage does increase, then the regulator should not have burned out.

Thanks guys. I'll do some tests with a multimeter and see if anything is amiss. The strange thing is that I haven't altered anything in the past year, so I'm not sure what the cause of this new issue is.

Also, does the part about the dynamo "sounding" like it is being switched off make sense? That is, under no load, I can hear steady mechanical noise coming from the dynamo. Once I hit the horn or the headlamp (load), that noise stops, as if something is shutting off the dynamo. I know it's still spinning of course, but does something else happen internally with the magnetic fields and whatnot that you can actually hear? I found this behavior odd, but had never noticed if any of it was happening before.

Hi Craig,

Regarding this noise:

When the dynamo is spinning and does not charge the battery for any reason-
The armature is rotating freely, with no axial resistance.

When it is starting to charge, the magnetic fields of the fluxes between
The armature and the field coil are crossing each other in order to generate
Electricity, a mechanical force is needed, in order to rotate the armature.
The higher the charge is (Current / Amps) the higher is the force /torque needed to rotate the armature.

Sometimes you can hear a "wailing" noise when that happens,
Either because of a worn dynamo bearing(s) and also, (I think..)
If the magneto sprocket is too tight with the idler on the timing side,
As the power needed to rotate the dynamo is passed trough the magneto
Sprocket from the idler.

Noam.

email (option): noam10@gmail.com

Hi Craig, I had similar problems. The dynamo would stop charging when the headlight was on. The trouble was the slip clutch on the mag drive sprocket slipping under load, because it had been greased. If your dynamo is worn the extra load may cause it to slip

Cheers Pat

Thanks Pat, I wasn't aware of the slipping clutch but I see it now in the manual. Good to know!

So, if this is the cause, I should be able to see the commutator stop spinning under load right? That would just about confirm this is the issue. I never bothered to look because I assumed it was all fixed gearing with the engine rotation! Looks like there are some lubrication points in there as well... also something I haven't checked.

Craig

It took a long time to realise that the mag clutch on my B33 was slipping. It was ok until I used the headlights then the charge rate dropped. I think the setting for the clutch is a 2lb pull on a 1 foot lever.

It took a while to sort everything out, but just to add this to the forum records (in case someone searches on this topic someday!), it turns out the fault was with the regulator, not the mag clutch. Swapped in a new DVR2 reg and it's working like a dream. Much better than the stock reg, and even better than the last electronic reg I had. Definitely a fan of the DVR2, and happy to not have to mess with the mag clutch (for now!).

Craig