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Discussion Starter #1 (Edited)
Here is the story:

Being the Safety Conscious guy that I am, I installed a High-Beam Head Light Flasher, for day-time use once the warranty was up (3 yrs).
Works great and it automatically stops flashing at dusk. Awesome so far, BTW head-on collisions have been avoided in this manner.

About 2 yrs after Flasher installation the RLU decides to quit because, after all, when the Head-Light Flasher Operates the RLU senses
this as a bad High-Beam and turns on the low-beam, so High-Low, High-Low we go. Well, now Only High-Dim-High-Dim.
I bought a good used RLU but didn’t install because it would just go bad again due to the Flasher. :(

Well, three years later the Voltage is lower while the bike is running then when I first placed a freshly charged battery in there.
With the Head-Lamp and Tail fuses pulled than I can get a decent voltage, but only 13.5V @ 4K RPM, with fuses in 12.78V @ 4K RPM.

The R/R gets hot, the Generator wires get Hot, the R/R fails “COLD” Meter Resistance Checks. I suspect a Diode got ‘tired’ of modulating
In rhythm with the Surge/Sag that the Head-Lamp flasher was causing (could also notice tail light flickering in rhythm).

So, the Big Fix: Replace the R/R, install the used RLU, Beef-up the Generator Wires, Install a LARGE Electrolytic Capacitor and go.

The thought here is that there is less of a Surge/Sag when you go from High to Low Beam during Flash. The lack of RLU caused a much higher
Surge/Sag potential working the R/R Diodes to death… Literally. The R/R is a completely sealed unit beyond economical repair, New $119-168.

OEM Head Lamp is 60W (5A) High Beam and 55W (4.58A) Low Beam: A fluctuation of .5A with SLU working instead of 5A on/off without.

Do you guys have any thoughts and/or experience with this?
 

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I have no clue but i am interested as I have a headlight modulator.
 

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All I can say is that, I myself have been using a Kisan headlight modulator for over 3 years now without any problems with the charging system. My regulator and rectifier were replaced over 3 years ago, before installing the modulator, and the original RLU is still the original.
 

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Linkmeister Supreme
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I am no electronic whiz, but I do not think the headlight MODULATOR should cause the RLU to fail in the manner which you describe. In my understanding, the reserve lighting unit senses when the operating headlight element fails by burning off or breaking. The modulator is not a "flasher" in the same sense that the turn signals are. The turn signals do operate in a cycle from completely open to closed, or zero power to 100% power over and over. Headlight modulators operate in a cycle from approximately 30-100% power, never completely shutting off, so should not trigger the RLU.

I do not know how to account for the electrical failures you have experienced with the RLU and r/r, but I suspect the cause is something other than the modulator.

So in response to your idea for the "big fix", you may need to replace the r/r, but normal operation requires it to get hot while grounding out excess current. I have no knowledge of any way to test the RLU other than replacing it. Regarding capacitors, I have a basic understanding of how one works in an old breaker points ignition system, where it charges and discharges for each plug spark. However I don`t quite follow how you think the capacitor is going to remedy the problem with the r/r and RLU. Is it going to cycle in step with the modulator? :confused:
 

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Discussion Starter #5
I am no electronic whiz, but I do not think the headlight MODULATOR should cause the RLU to fail in the manner which you describe. In my understanding, the reserve lighting unit senses when the operating headlight element fails by burning off or breaking.
Thank You for your input/comments.

I can say with 100% certainty that when the RLU is working and the Modulator is active, I see both the High and Low Beam alternate as well as a failed head lamp indicator flashing on the Dash.

The thought on the Capacitor is to keep the Voltage constant so the R/R is not swinging to meet the demands of the modulating load, they essentially will be absorbed by the discharging capacitor.
 

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The thought on the Capacitor is to keep the Voltage constant so the R/R is not swinging to meet the demands of the modulating load, they essentially will be absorbed by the discharging capacitor.
A capacitor will have very little effect to the operation of the charging system. For under 120$ you can find a 0.47F capacitor which discharges to a 60W load (headlamp) from 14V (charging voltage) to 12.6V (battery idle voltage) in about 0.12 seconds. A cheaper, under 20$, 0.1F capacitor discharges in 25 milliseconds. And you would have to put in a power diode to prevent the capacitor from supplying the power to the whole system instead of the headlamp only.

The R/R will try to maintain a constant charging voltage. As soon as the capacitor voltage drops below this, the current comes from the R/R anyway.

What I am trying to prove here is, that installing a 'buffer' capacitor is useless.

If I understood correctly, you said that the modulator switches between high and low beam. If this is the case it might help to install large capacitors between the modulator input and outputs. This connection however will cause the capacitors to be discharged through the modulator, and the modulator may not withstand it.
 

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As an aside, I wonder about our perceptions of ourselves on our bikes. We find it perfectly normal to ride with expensive flashing headlights and tail lights, or simmilar gadgets, some with questionalble effect, some pretty good. Some of us don't bother, but we accept it as a reasonable response to dangerous drivers.
But NOT ONE OF US has ever considered riding around with our four-way flashers on.
We would think that it would make us look afraid, or just odd. It would be a heck of a lot cheaper, and would not change any circuitry.

What are your thoughts?
 

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Discussion Starter #8
As an aside, I wonder about our perceptions of ourselves on our bikes.

But NOT ONE OF US has ever considered riding around with our four-way flashers on.

We would think that it would make us look afraid, or just odd. It would be a heck of a lot cheaper, and would not change any circuitry.

What are your thoughts?
In most states if you are running the speed limit with your flashers on you will get pulled over and questioned about the "Emergency."

I have put them on, briefly, in heavy traffic on the highway when things slowed quite quickly.
 

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Junkyarddog said he ran them at 35 mph and below.
 

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Discussion Starter #10
Adding Capacitor Across Modulator Input

If I understood correctly, you said that the modulator switches between high and low beam. If this is the case it might help to install large capacitors between the modulator input and outputs. This connection however will cause the capacitors to be discharged through the modulator, and the modulator may not withstand it.
Thank you for the comments.

The RLU briefly switches on Low Beam when the Modulator switches off the High Beam.

In the Electronics Engineering world Capacitors are placed across a changing load, such as Electronic Switches, to smooth out the fluctuations in the Power Supply Stage.

In this case, the Headlight Modulator is an Electronic Switch so a Capacitor across the Modulator Input would help protect the R/R, in Theory.
 

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Discussion Starter #11
Stator Checks

Bad Stator Winding?

Stator Winding Cold Checks

A to Ground .3 Ohms A to B .5 Ohms
B to Ground .7 Ohms A to C .5 Ohms
C to Ground .7 Ohms B to C .5 Ohms

Is it safe to say that the Stator Wire 'A' is Shorted to Ground?

The STAR configuration means if one lead is Shorted to Ground, then they
all show a Short to Ground, although slightly higher as they have to pass through the additional coil to get to the Ground.

Stator Winding HOT Checks

A to B 1.4 VAC
A to C 1.4 VAC
B to C 34 VAC

So the question is did the Head Light Modulator take out the Stator?

I want to offer my sincere gratitude and thanks to this site and the riders contributing to it for reducing my diagnostic time and co$t. Thank You
 

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The RLU briefly switches on Low Beam when the Modulator switches off the High Beam.
I see. Then I don't think there is anything you can do about it unless you bypass the RLU.

In the Electronics Engineering world Capacitors are placed across a changing load, such as Electronic Switches, to smooth out the fluctuations in the Power Supply Stage.
True, but in this case the switched current is so high and the switching frequency so low that the capacitance would have to be impractically high. And our 'Power Supply Stage' low frequency impedance is quite low. ..unless you mean filtering out voltage spikes, for which a much smaller low impedance capacitor will do.

In this case, the Headlight Modulator is an Electronic Switch so a Capacitor across the Modulator Input would help protect the R/R, in Theory.
Since the headlight is a resistive load, switching it on/off does not generate voltage spikes, so no protection is needed, in Theory;)

So the question is did the Head Light Modulator take out the Stator?
No it did not. The R/R abuses the stator a lot worse by constantly shorting it out.
 

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Discussion Starter #13
No it did not. The R/R abuses the stator a lot worse by constantly shorting it out.
I tend to agree. The mechanic were I bought the bike said in his experience it is the use of the side stand that allows hot oil to pool on that side of the engine, thus "Baking" the Stator and in doing so breaks down the enamel coating on the windings.

He strongly urges riders with a center stand to use it instead.

Any thoughts on this?
 

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The mechanic were I bought the bike said in his experience it is the use of the side stand that allows hot oil to pool on that side of the engine, thus "Baking" the Stator and in doing so breaks down the enamel coating on the windings.

He strongly urges riders with a center stand to use it instead.
Oh...my....god! That is such nonsense. 1) Oil doesn't even reach the stator windings when pooled in the crankcase and 2) the oil is probably 100 deg. F cooler than the stator magnet wire gets during operation. If anything, stator failure is due to not enough oil getting to the windings during engine operation. I installed a 3-inch sight glass in a spare timing cover to monitor the windings and there is the slightest mist of oil circulating around inside the flywheel.

I wouldn't go back to that mechanic.
 

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Discussion Starter #15
Install an Inductor?

True, but in this case the switched current is so high and the switching frequency so low that the capacitance would have to be impractically high. And our 'Power Supply Stage' low frequency impedance is quite low. ..unless you mean filtering out voltage spikes, for which a much smaller low impedance capacitor will do.
:huddle:

Should I install an Inductor (Coil) across the Modulator to "Soften" the Current spikes?
 

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Should I install an Inductor (Coil) across the Modulator to "Soften" the Current spikes?
For that purpose the coil would have to be in series with the load. It would resist sudden current changes, but would create voltage spikes. To eliminate the spikes you could put a RC snubber across the modulator input and output, but I honestly don't think you need to install a coil or a capacitor because of the modulator.
 

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CQ w4nmh - hello O.M. - wouldn't an inline hi V ; hi A diode placed on the High Beam lead between the modulator connection and the RLU keep the RLU happy? "wd4ryx"
 

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Discussion Starter #18
Stator Replaced.
20K Mile Service DONE!
RLU Replaced.
R/R Replaced (Still good but 8 yrs old).
AMCCT Replaced

I'm on the Road to Recovery...

Rich
 

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Discussion Starter #19
WD4RYX De W4NMH

I'd have to check the schematic.
I'm thinking you would have to wire the High Beam around
the RLU while also satisfying it (anything like marriage?).
 

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To keep the RLU happy, you need to have a load on it all the time. Here is a principle of a circuit to accomplish that. When the modulator switches the high beam off, the low beam is switched on instead. Are you handy with a soldering iron? ;)



Edit:
How about this simpler version?
 
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