Topic: solid state reg/rectifier installation

[hymodyne]

back in march, I installed a solid state reg/rectifier I bought on my '72 K1 cb500. It didn't work, so I re-installed the old reg and rectifier. to date, after replacing one battery that was about 3 yrs old with a new one, I consistently have issues with the charging system of this bike; with a full 13+ volt charge on the new battery, by the end of a day of diagnostic rides and operation, the battery struggles to start the engine.

I have read the threads about checking connections and grounds throughout the harness and bike systems, as well as threads on using a voltmeter to check the elec. system out. but here's the thing; I want to ride the bike, not work on it all summer, so, if possible, could some kind soul help me re-re-install this solid state device so I can get on the road? I'm torn down (again) to replace the center shift fork  , so I have the time to check out the wiring with a volt-ohm meter while I wait for my new fork to arrive.
that being said, I'd like to install this new unit which has a black and white wire coming out of one bundle, and a six wire bundle consisting of three yellow wires, one black, one red and one green. help in getting this installed on a 500K1 would be greatly appreciated

I've been working on this bike all winter, between a 3 week trip to Africa (two of my colleagues caught malaria) and the completion and defense of my dissertation in English literature. today was the last day of classes at my old college and I'm slated to begin a new job at a university in Maryland in august...I need some fun.

help a rider out,

hym

[Bodi]

If you want to ride and not work on it all summer, fix it properly now. Spend the time to clean all the harness connections.
The original rectifier and regulator should be fine if the harness has been renovated.  The rectifier is easy to test in 5 minutes with a VOM. The regulator is pretty easy to test with a running bike, there should be no voltage between black and white wires if the battery is below 13 volts or so: booth black and white wires should be at or very close to battery voltage - if the battery measures 12V the the black wire at the regulator should be over 11 volts.

[TwoTired]

How do you know the vreg or rectifier you have is bad?

If, for example, the alternator field is bad,  You can replace everything in the rest of the bike, and it still won't charge.

What have you changed in the way of electrical loads, different than what the stock bike had?  Brighter headlight?

How good is your ohmmeter technique?  How accurate is your ohmmeter?  Do you have a proper wire diagram for your bike?

I hear you about wanting to have some fun.  Unfortunately the bike doesn't care.  Until you give it what it needs, it won't share the fun.  Don't lose patience with it.   Be deliberate and methodical.  It will reward the attention only with work performed correctly, and completely.

I can help from here.  But, I'll need data that you must provide.

Cheers,

[twisting_edge]

I think the goal here is to try the new part and see if that fixes the problem. If it works, it works. If not, then he can start worrying about the rest of the wiring.

Is there a FAQ anywhere on retrofitting modern parts to an old bike? It seems that would be a good idea, as original parts become more and more scarce. Having it all in one place would be nice.

My electrical system seems fine now, but two weeks ago I would happily have bought a bunch of new electrics and just replaced tons of stuff. It turns out that's not what was needed, but given the bike's recent history (total immersion on two occasions for several hours each), it probably would have been a good idea in any case.

I have to admit the old parts must be built like a battleship: tons of redundancy and fault tolerance. There's no other way that bike should be running at this time.

[TomC]

Hi hymodyne
     "The rectifier is easy to test in 5 minutes with a VOM." I am sick and tired of this piece of nonsense. I have both an analog and a digital VOM neither with do this. Use a test light!!!!!!!!!!!!!!!!!!!!!!!
           TomC in Ohio

[TwoTired]

Hi hymodyne
     "The rectifier is easy to test in 5 minutes with a VOM." I am sick and tired of this piece of nonsense. I have both an analog and a digital VOM neither with do this. Use a test light!!!!!!!!!!!!!!!!!!!!!!!
           TomC in Ohio

I think you need to explain this, TomC.  As, it seems to me that it wreaks of bovine excrement.  Well, except the for the "sick and tired" part, of course.

Cheers,

[hymodyne]

How do you know the vreg or rectifier you have is bad?

If, for example, the alternator field is bad,  You can replace everything in the rest of the bike, and it still won't charge.
True. i'll do that as soon as I can study the manual on it.
What have you changed in the way of electrical loads, different than what the stock bike had?  Brighter headlight?
two led front turn signals on each side. no running lights. rear turn, driving lights, license lamp, halogen headlamp.(4) led idiot lights, lamp for oil pressure gauge, dyna ignition, accel coils & non-resistor wires.
How good is your ohmmeter technique?  How accurate is your ohmmeter?  Do you have a proper wire diagram for your bike?
simple measurements of ac/dc current and resistance. I can follow instructions. I'll look through past threads. I have the honda manual for the 500&550 on CD.
I hear you about wanting to have some fun.  Unfortunately the bike doesn't care.  Until you give it what it needs, it won't share the fun.  Don't lose patience with it.   Be deliberate and methodical.  It will reward the attention only with work performed correctly, and completely.
There. I read these lines to my girlfriend, a fellow sufferer in my quest for two-wheeled mobility, and she laughed as I, the professor was squirming while being taught. She digs the fact that I have a community like this one to interact with.
I can help from here.  But, I'll need data that you must provide.
Its appreciated. I'll be talkin to you and the rest who wanna help.

Many thanks,
great site,

hym

Cheers,

[TwoTired]

Trying to work up a power budget for your modified bike...  What wattage headlight did you install?  And, what was the ohm rating on your coil primaries?
These were the only yellow flags I saw.  Hope they don't turn red.

Since you don't have a motor in the bike,  voltage tests can be a bit tricky, though doable.  But, in the mean time you could test you ohmmeter technique on these tests.

First determine your test apparatus error.  Meter on lowest ohms scale, touch probe tips together.  Note reading.  Subtract this number from all future measurements on this scale.

Battery disconnected:  Ignition switch on.
Measure from battery POS cable terminal to VReg white terminal (Disconnected).  Then again to black terminal  (connected).
Measure from battery NEG cable terminal to VReg Grn terminal .
(Okay, since your engine is out, pick a place where the motor makes electrical contact with the frame instead of the Battery NEG terminal.)
Measure ohms from Vreg white wire (disconnected) and the VReg green wire.

It's a start...

Cheers,

[oldfart]

Using a meter of any kind is the worst possible way (okay, maybe there are worse ways, but I can't think of any) of testing a rectifier.  Anybody who has spent more than a month as a professional motor vehicle tech will tell you this.  The best and really only (completely conclusive) way to test a recitifer is by measuring what is going into it and what is coming out. 

http://home.earthlink.net/~trinomial/SOHCcharging.html
http://www.motorcycleproject.com

[hymodyne]

here's an update that will probably help explain things...

accel 3 ohm coils
halogen H4  100/90W headlight.

also I tested my field coil: 4.9 ohms (-.003)
stator coil: 1.0-1.1 on each test.
I'm going to look in to a lower 45/55W halogen bulb tomorrow, and will check threads here about stator coil readings.

other tests soon,

hym

[TwoTired]

Yikes!!
Your alternator puts out 150 Watts at 5000 RPM and about 40-50W at idle.
The stock bike draws about 120 -130 watts, to which you added 60-65 watts with the headlite and coil mod.  That's 180 watts,  30 more than your charging system, in peak condition, can put out before 30 years of wire and connector deterioration, which can easily waste another 20-30 watts.

Yep, the battery can't ever be charged by the bike.

Your Field coil and Stator measure fine by the way.  But, a new headlight is pretty good first step!

Cheers,

[hymodyne]

many thanks.

I'll post an update once my center shift fork gets here and I'm up and running again

hym

[Bodi]

Measuring what goes in and what comes out without an oscilloscope and current probe is not useful for checking a rectifier. Using an analog ohmeter or a digital meter with a diode test function is the best way possible. It takes only minutes with a disconnected rectifier and gives a 99.999% accurate indication whether the 6 diodes are all good or not. Period.
Auto techs aren't much of a good example. They follow a flowchart to hook up the diagnostic computer wires where the book says to, and thenthe computer tells them what part to replace. I wouldn't trust most of them with a meter.

[hymodyne]

I just picked up a 55/60 halogen bulb, to replace the 90/100W one I had been killing my battery with. as far at the Vreg is concerned, is there a rule of thumb as to how much the points gap should be adjusted to increase voltage output withhn the system to compensate for the headlight and 3 ohm coils? Specifically, 1/4, 1/2, etc. turn of the  points adjusting screw ,  in correlation to the increased approx 160 watts being consumed.

dont want to boil my new battery,

hym

[TwoTired]

I just picked up a 55/60 halogen bulb, to replace the 90/100W one I had been killing my battery with. as far at the Vreg is concerned, is there a rule of thumb as to how much the points gap should be adjusted to increase voltage output withhn the system to compensate for the headlight and 3 ohm coils? Specifically, 1/4, 1/2, etc. turn of the  points adjusting screw ,  in correlation to the increased approx 160 watts being consumed.

dont want to boil my new battery,

hym

The voltage regulator in the this system is misnamed in my opinion.  It is a voltage limiter in actuality.  It's function is to keep the battery voltage from getting so high as to boil and damage the battery.  When the the voltage gets too high, it tells the alternator to back off so as not to cook the battery.  The Vreg cannot make the alternator provide more power than it is capable producing, only throttle back power when it is producing too much.  The system voltage on the bike is dominated by the battery state of charge, which both the alternator and bike system loads can effect.

The vReg limits power by reducing the electromagnetic field developed inside the alternator.  This power is determined by the voltage delivered to it on the white wire and the rotational speed of the rotor attached to the crankshaft.  When the battery voltage gets too high the Vreg stops routing the 12v direct from it's black wire to the white wire.  Instead, it inserts a resistance to lower the voltage delivered on the white wire.  This reduces the magnetic field in the alternator and it's power output, whatever its rotational speed (if non-zero).  This is why it is so important to have full battery voltage at the black wire to the Vreg.  The percentage of reduction here represents a percentage of production capacity by the alternator.  If you cut the voltage to the Black, and therefore White, wire by 50%, the alternators output drops by at least 50%.  (It's not actually directly proportional, but extra complexity won't help this discussion).  If you are not getting the full battery voltage at the white wire, your alternator can't even make 150 Watts, ever.

The alternator peak production is 150 watts at 5000 RPM when the field is provided with 12V.
I've never tried, but in theory, you could increase the alt. power output by raising the filed voltage higher than 12V or higher than what the battery can provide.  Schemes with DC-DC converters come to mind...
However, it is going to take some significant engineering to have people lift a truck with one hand.  Simply feeding them Wheaties or even steroids, is unlikely to achieve that goal.  However, if you made the truck out of balsa...

I've been testing/checking diodes with an ohmmeter for more than 30 years.   Found good ones, found bad ones, found weird ones, too.  Anyway, your rectifier simply as six diodes inside.  If your test technique it at all reasonable, your ohmmeter can give you data to determine their functionality.  If your meter has a -|>- symbol, use that setting.  Good diodes show low resistance with one probe polarity, and high resistance with the other probe polarity.  There is a diode between each yellow connection and the green wire, and another diode between each yellow wire and the Red wire (might be Red/wht).  It will take 12 measurements to verify or condemn your rectifier.

Cheers,