This feels like a dumb RR question...

[shamer]

But I'm not the first to ask it as I found it asked but unanswered in another post while searching:

In reference to the Stator Papers testing, at the beginning of the fault finding chart it says to test the RR by putting the multimeter black to the battery & the red to the output[red] of the RR and check the voltage for above or below .2V. My question is this: does a negative reading mean anything? Would (in this case) a reading of around -.3V be considered less than .2V? I know, stupid question - my instinct tells me that it doesn't matter whether it is + or - and that my RR failed the first test & I need to recheck the wiring. Other tests of the RR were passed as well as the stator itself but I'm still not getting a reading at the battery any higher than around 12.6 - whether idling or reving to 5000.

Despite the great wealth of info here, I've been left slightly stumped by this RR problem. I just bought the bike a few months ago (1980 GS850L w/only 25K on the clock, but I still had to put A LOT of love into it) and in fact had just come back from an 1800 mile road trip with it last week when it failed to start & I discovered a trashed battery. I've tried routing the ground directly to the battery which had no effect on raising the battery charge reading. The only thing I have not tried is routing the positive directly to the battery, but I guess that's next on the agenda... (BTW, if I put an in-line fuse between RR red and the battery positive, what amp fuse should I use?).

Two more questions:

1) It was obvious to me that the RR had been replaced before (splices & wire nuts - yes, I cleaned those up with proper connections) so I'm not sure what RR is on my bike now as there are no identifying marks other than 3 silver numbers on the back ( 2 0 0 ) - any other way to tell? It has 3 yellow wires for stator connections so I'm guessing it isn't a Suzuki/Nippon Denso one.

2) I picked up a '78 Shindengen 232-12 for cheap while I had the chance as a spare but I'm not sure how to test it as I get either no readings or failed readings when I do the diode testing as per the fault-finding chart. I'm guessing it is because of the extra sensor wire but I have not counted out the Honda RR as being shot. Is there an alternate testing method for these because of that extra wire?

Thanks in advance, this is my first post but I've been lurking and spending hours searching/reading here since I bought the bike. This forum is great & reminds me a lot of the mitsubishi 4x4 forum (4x4wire) that I frequented for many years - lots of info & you guys sound like fun so I hope to meet up on a GS cruise sometime!

Shawn

1980 GS850L

 

[shamer]

Can I bribe a response with mediocre photos? This one is from my recent 1800 mile road trip through upper & lower Michigan a few weeks back and was taken near Copper Harbor, MI at a rest stop along a gorgeous bit of lakeshore highway full of butterfly inducing whoops, dips & twisties....

 

[jm_foote]

I think a negative means you had the black and red wires backwards (probobly on the multimeter). Unless checking diodes, you can normally assume an absolute value when checking voltage.

 

[Boondocks]

In reference to the Stator Papers testing, at the beginning of the fault finding chart it says to test the RR by putting the multimeter black to the battery & the red to the output[red] of the RR and check the voltage for above or below .2V.

This test require that the digital multimeter be set to the "diode check" position, not DC volts. Did you use this setting when you checked it?

In my opinion, the bench tests for the stator and R/R are useful only when you are buying one from a junk yard or somewhere where it can't be tested on the bike. Static bench test results may pass, but the components can still fail under load when installed and rigorous actual working conditions and heat are applied.

The best tests are run at 5,000 rpm: The disconnected OEM stator leads should have equal voltage of about 80VAC. Aftermarket stators may test with 50 volts or more due to wiring differences, but should still have equal readings on all three leads.

If the stator tests OK, all connections are clean and well grounded, and the bike won't charge over 14VDC at 5,000 rpm, then the R/R should be replaced. I would just plug in your SH232-12 R/R and see if the battery charges properly. Don't bother with bench testing it. Make sure that the sense wire is connected to a circuit which is hot only when the ignition is on, like the tail light. If you want to connect the red lead directly to the battery, try a 15A fuse first or a 20A if it blows. I would recommend that you not do this, but connect it to the normal red lead connection in the wiring harness. Running the R/R ground wire directly to the negative battery terminal is a good idea. A good R/R should charge the battery in the 14.0-14.8 range at 5,000 rpm.

 

[shamer]

This test require that the digital multimeter be set to the "diode check" position, not DC volts. Did you use this setting when you checked it?

You know, I didn't switch it to diode testing until later when it specifies to do so. That may explain my funny readings. Now that I have time to attack this again, I'll try more intensive testing this weekend.

I'll post a pic of the RR that I have later to see if anyone can help identify it...

Thanks for the input!

 

[shamer]

Here's pics of the yet unknown RR - if anyone recognizes it please let me know!

 

[shamer]

Start from scratch on RR problem

Start from scratch on RR problem

Okay, I know the stator/RR subject gets beaten to death quite a bit on this board, but I think it's because of the shortcomings of the info available on the the Stator Papers. You inevitably end up searching through scores of posts on the subject here in the forums to get more info (which you find) but sometimes there are inconsistencies and contradicting info that you also find.

For instance, the RR on my bike gives questionable readings for each of the tests concerning just it - and if you consider it failing the solutions don't make sense in my situation (clean connections - cripes, I soldered new ones with no change!) or there is no solution (e.g., my readings fall between pass and fail for Test Phase C). I even made a 14 guage Y lead with which I connected the RR (+) out directly to the battery (+) via a 20 amp blade fuse which had no effect on readings when the solution said 'bad connections'. Anyway, here are my results from beginning to end:

BATTERY IS BRAND NEW & FULLY CHARGED.
Battery charge with ignition off: 12.62V (engine not running)
Battery charge with ignition on: 12.2V (and falling - engine not running)
START
Battery charge idle (1200RPM): 12.27V
Battry charge revving (2500RPM) 12.28V
Battery charge revving (4500-5000RPM): 12.26V
MultiMeter (-) to BAT (+) | MM (+) to RR (+): -.42V (V) or -.28 (Diode) (passing supposed to be <.2V - yes my readings are negative (-) values!)
MM (+) to BAT (-) | MM (-) to RR (-): bypassed [lead straight to BAT (-)]
TEST PHASE B
Stator 3 wire resistance reading: all around 1.0 Ohms
Stator short test: all read infinite resitance (no short)
Stator AC readings: all three are at 35V (idle) and 80V (5000RPM)
TEST PHASE C
RR disconnected.
MM (+) to RR (+) | MM (-) to each Yellow: each reads 1.32V (<1.0V=fail, >1.5V=pass, 1.3V=?)
MM (-) to RR (+) | MM (+) to each Yellow: .41V, .41V and .42V (~.5V =pass)
MM (-) to RR (-) | MM (+) to each Yellow: each read 1.32V (again, falling between pass & fail)
MM (+) to RR (-) |MM (-) to each Yellow: each read .40, .41 and .41 (again, ~.5V=pass)

I ran these test a couple of times (charging the battery between) with consistent results.

I then installed a '78 SH232-12 - I spliced a 14 guage Y (w/soldered bullet connectors) to the tailight positive lead and connected that to the black wire of this RR. I was bit disturbed by the low reading of 10.7V at this wire - is this significant? I ran a lead directly from the RR green wire to the battery (-) terminal and all other connections are otherwise the same as other RR. Here are my test results:

BATTERY FULLY CHARGED.

Battery charge with ignition off: 13.08V (engine not running)
Battery charge with ignition on: 12.5V (and falling - engine not running)
START
Battery charge idle (1200RPM): 13.1V
Battery charge revving (2500RPM): 15.1V
Battery charge revving (4500-5000RPM): 15.5V to 16.0V
MultiMeter (-) to BAT (+) | MM (+) to RR (+): completely depended on RPMs - below 1000RPMs is passing but it continues to rise with RPMS & reaches a 'failing' level .21V at about 2000RPM
MM (+) to BAT (-) | MM (-) to RR (-): bypassed [lead straight to BAT (-)]
TEST PHASE B -- same as previous test.
Stator 3 wire resistance reading: all around 1.0 Ohms
Stator short test: all read infinite resitance (no short)
Stator AC readings: all three are at 35V (idle) and 80V (5000RPM)
TEST PHASE C
RR disconnected.
Testing this Honda RR via the above method simply doesn't work, so I have no readings to provide.


So I guess, the SH-232-12 is working but I'm concerned about the fact that it is charging so high and that it has variable readings for the positive lead test. I tried the Y cable/blade fuse lead that I made earlier on the RR as well & got even higher charging readings so the diagnosis that there's a bad connection to the battery (+) doesn't fly here. I'm assuming that the variable readings are because of the 'sense wire' (tail-light lead) and perhaps the low reading (10.7V) I get there can be the cause of the higher than ideal charging rate, right?

And, finally, a real question:

Since these old GS bikes seem to spend a lot of time around 5kRPM, is it okay to have an RR that is spitting out nearly 16V at that range? Will I be buying batteries left & right? Is there anything I can do (add) to drop that voltage down?

I know I'm long winded (fast typer) so thanks for hanging in there if you've bothered to read this far...

 

[earlfor]

I think your problem is the low voltage on the tailight wire that you have the 232 voltage sensor wire connected to. Voltage on the tailight should be close to the same as voltage at the battery terminals with the engine not running. I think if you will locate and correct the voltage drop on your tailight wire, you will find the 232 will regulate the charge rate correctly. Or, you could connect the sensor wire to another supply source such as the ignition switch.
It would be a better choice to fix the original problem though in my opinion.
The charging voltage youre getting now is way too high. It will shorten bulb life and ignition system life plus cook batteries. Average charge rate when tooling down the highway with everything on is no more than 14.2 to 14.6 regardless of how high the rpm. Up to about 14.8 is ok, but thats the max you want to see. Low 14's is better.

Earl

I then installed a '78 SH232-12[/B] - I spliced a 14 guage Y (w/soldered bullet connectors) to the tailight positive lead and connected that to the black wire of this RR. I was bit disturbed by the low reading of 10.7V at this wire - is this significant? I ran a lead directly from the RR green wire to the battery (-) terminal and all other connections are otherwise the same as other RR. Here are my test results:

 

[Boondocks]

Yes, the whole point of the voltage sense wire is to read the true battery voltage instead of reading through the R/R output wire which may be inaccurate if a connection(s) are corroded. The voltage drop in the tail light circuit is significant and will cause the R/R to read the battery voltage as only 10.7V.

When the sense wire reads an inaccurate low voltage, the R/R will raise the output voltage to an unacceptably high voltage trying to match its output to the bogus battery voltage from the sense wire. Your tail light is probably much dimmer than it should be, and a voltage drop of this magnitude should definitely be fixed.

 

[shamer]

Thanks a ton, guys - I really appreciate you taking the time to walk me through this.

When I first noted the low measurement at that wire, I did check the bullet connections leading to the tailight & they all seemed fine. I have not popped the tailight itself open yet & as you can probably tell, electrics aren't my strong point - is there anything in particular to watch out for? What kind of things cause voltage drop? I know distance and resistance can do that - and many lightly corroded connections could raise the resistance of the path & lower the voltage, right? Is that it? I mean, this seems like a pretty significant drop...

Thanks again!

Shawn

 

[Boondocks]

Yes, it's usually corroded or loose connections or bad grounds that cause this type of voltage drop, or a combination of same. It could also be a bad switch, i.e., if the ignition switch was not making good contact it could drop voltage all over the bike.

Corrosion on connectors isn't always easily seen, as all it takes is a thin film of oxidation to raise the resistance enough to cause a voltage drop. Radio Shack has a closeout on Caig DeoxIT, which is a very effective oxidation remover. It is normally very spendy, but Radio Shack is selling it for $1.97 if you can still find it. Electrical grease is also helpful in preventing corrosion.

 

[shamer]

I'll make a note of that - I actually find myself at my neighborhood Radio Shack fairly often, but unfortunately they seem to becoming more of a Five & Dime than what I expect them to be so that's beginning to happen less frequently...

Well, I went through a good portion of the wiring and spent a lot of time just taking connectors apart & putting them back together, using a bit of WD-40, sandpaper & bulb grease when possible. Made a little difference anyway - I'm at a maximum of 15.7V through the revs up to 5800RPM and at idle (~1200RPM) it flirts with 13V. Is this acceptable yet? [-o<

The only other thing to note is that when I pulled the headlamp bulb I discovered that the sensor wire connection went from its 10.7V up to 11.4V. Seems pretty significant, but I'm not sure what that tells me other than that headlight sucks up a bit of juice. As I connected/disconnected the lamp you could see the difference in the brightness of the tail light (it was twilight out). Does this tell you anything?

 

[earlfor]

The rear turnsignals and tailight are usually isolated and rely on a wire for ground which usually terminates in a ring connector held down with a bolt. I would check grounds on the tailight assembly/turnsignals before progressing to trying to track down voltage drops and corrosion in the 12v+ supply wires.
Oftentimes, I have found voltage drops are cumulative and dont find all of the problem in a single connector or location.

Earl

Thanks a ton, guys - I really appreciate you taking the time to walk me through this.

When I first noted the low measurement at that wire, I did check the bullet connections leading to the tailight & they all seemed fine. I have not popped the tailight itself open yet & as you can probably tell, electrics aren't my strong point - is there anything in particular to watch out for? What kind of things cause voltage drop? I know distance and resistance can do that - and many lightly corroded connections could raise the resistance of the path & lower the voltage, right? Is that it? I mean, this seems like a pretty significant drop...

Thanks again!

Shawn

 

[Boondocks]

Well, I went through a good portion of the wiring and spent a lot of time just taking connectors apart & putting them back together, using a bit of WD-40, sandpaper & bulb grease when possible. Made a little difference anyway - I'm at a maximum of 15.7V through the revs up to 5800RPM and at idle (~1200RPM) it flirts with 13V. Is this acceptable yet?

No. 15.7V is way too high and will fry the battery.

The only other thing to note is that when I pulled the headlamp bulb I discovered that the sensor wire connection went from its 10.7V up to 11.4V. Seems pretty significant, but I'm not sure what that tells me other than that headlight sucks up a bit of juice. As I connected/disconnected the lamp you could see the difference in the brightness of the tail light (it was twilight out). Does this tell you anything?

Yes and no. Yes, turning the ignition/lights on without the engine running puts a load on the battery and will cause the voltage reading to drop a bit as long as it is loaded without charging. No, this isn't sufficient to explain the size of the voltage drop at the sensor connection.

My theory is that the corrosion problem can't always be eliminated by a simple cleaning of connector surfaces. Crimped connectors are typically made of a different material than the wiring, and have a different coefficient of thermal expansion. That is, when the wire and crimped terminal go through enough heat/cooling cycles, the crimp connection may be compromised and air may enter and form oxidation between the inside of the crimp and the wire. Cleaning the oxidation from outer surfaces helps, but doesn't reach the critical inside of the crimp. I think that to bring the wiring back to original conductivity, you would have to install new crimped connectors or solder the wires together. If a person doesn't have the right know-how and tools, they can do a really poor job of installing new crimp connectors. Same with soldering, but most people on this forum have solved electrical connection corrosion problems by removing the connectors and soldering the wires together.

Fixing the voltage drop is an interesting challenge, but I would want to be certain that the R/R is working properly before investing too much time running down voltage drops. I would temporarily connect the sense wire directly to the battery positive terminal and start the engine and run it at 5,000 rpm to see if the voltage stabilizes in the 14.0-14.8 range. If so, this is the proof of the pudding that you have a good R/R and the voltage drop is causing the overvoltage condition. If not, the R/R is bad and you will need to get another. Don't worry about the temporary connection of the sense wire to the hot terminal. It isn't normally done this way because it will cause a battery drain when the ignition is off. This is why it's connected after the ignition is turned on.

 

[earlfor]

Turning off the headlight and it resulting in a temporary voltage increase (engine running) is normal. Sorry, but 15.7 volts is completely unacceptable. Maximum acceptable under any condition, at any rpm, is 14.8v. I have returned new R/R's that charged at 15 volts as faulty and they have been replaced by dealers at no charge.

Earl

I'm at a maximum of 15.7V through the revs up to 5800RPM and at idle (~1200RPM) it flirts with 13V. Is this acceptable yet? [-o<

The only other thing to note is that when I pulled the headlamp bulb I discovered that the sensor wire connection went from its 10.7V up to 11.4V. Seems pretty significant, but I'm not sure what that tells me other than that headlight sucks up a bit of juice. As I connected/disconnected the lamp you could see the difference in the brightness of the tail light (it was twilight out). Does this tell you anything?

 

[Steve]

It is telling ME that there might be a bad connection between the battery and the light circuit. Might be bad contacts in the fuse holder or broken strands in the wiring. Just for fun, check the voltage at the headlight fuse (with the bike running). Check the voltage at both sides to see if it is the same. If it is low at the fuse, check the wire that feeds the fuse for broken strands. Might even consider replacing it with a larger wire. Bikes are rather notorious for inadequately small wiring. A headlight will draw about 5 amps, the rest of the lights a couple more. When the brakes are on, add another 2 1/2 amps per brake bulb (some bikes have more than one). Figure there might be around 10 amps possible draw. The books say that 16 gauge will be adequate, but 14 or 12 gauge will be even better. If the supply is limited for ANY reason (corroded connections, small wire, etc.), sufficient current can not flow, and voltage will suffer. That is why the voltage rose as much as it did when you disconnected the headlight. I would expect a bit of a rise, but not that much.


.

 

[shamer]

Well,

I just can't seem to narrow down exactly where the problem is here - at least not any further than the headlight.

Today I took apart the fuse block & cleaned everything up. Voltage from the battery to the fuse block is good and so is the ground. I measured resistance between battery (+) and each fuse circuit (ignition on for the switched ones) and all were fine EXCEPT, of course, the headlight fuse which measured about .5 Ohms higher than the others. This mesurement held true when going from the fuse block to the headlight itself so I know it is somewhere along that path. I just can't narrow it down to where - I even pulled the gas tank & went through each connector but that made no difference. Hmmm, I wonder if it could be in the hi/lo beam switch - does current actually travel through that switch? Maybe I'll go check that right now...

Thanks again to each of you! If I can get this part figured out I should be pretty good - I hope. When I pull the headlamp out & run the bike I get a perfectly within spec charge of 14.6V at the battery. I just hope that it'll stay within spec after I get this sorted out...

Shawn

 

[crc1214]

Turning off the headlight and it resulting in a temporary voltage increase (engine running) is normal. Sorry, but 15.7 volts is completely unacceptable. Maximum acceptable under any condition, at any rpm, is 14.8v. I have returned new R/R's that charged at 15 volts as faulty and they have been replaced by dealers at no charge.

Earl

Earl, I used to think 14.8 was the max as well, but 15.5V is completely acceptable according to Suzuki, at least in my manual for my 83 750E. I couldn't believe it when I read that, but it's true. 15.5 is the MAX, but 15.5 it is. And the battery used in that model is a 14L-A2, which from what I've gathered is used in 99% of the GS's (except of course when a combine battery stashed in a backpack must be used.....LOL!!)
Anyhow, mine charged at 15.5 too, it would never go above, but it would get up there and stay up there because I pretty much stay above 5,000 RPM's at all times. Now granted, I was using a sealed battery in it, but I never had any problems with the battery or with any bulbs blowing or anything.

 

[Boondocks]

Earl, I used to think 14.8 was the max as well, but 15.5V is completely acceptable according to Suzuki, at least in my manual for my 83 750E. I couldn't believe it when I read that, but it's true. 15.5 is the MAX, but 15.5 it is. And the battery used in that model is a 14L-A2, which from what I've gathered is used in 99% of the GS's (except of course when a combine battery stashed in a backpack must be used.....LOL!!)
Anyhow, mine charged at 15.5 too, it would never go above, but it would get up there and stay up there because I pretty much stay above 5,000 RPM's at all times. Now granted, I was using a sealed battery in it, but I never had any problems with the battery or with any bulbs blowing or anything.

A 100% fully charged standard flooded lead-acid battery has a resting voltage (no surface charge) of 12.65V. A 0% fully discharged battery has a voltage of 11.89V or less. Thus, only 0.71V difference between 100% charge and fully discharged.

Charging a battery is a compromise. In order for a battery to fully charge, it must have some gassing, the bubbles released when the water in the electrolyte is "boiling". Gassing begins at about 14.2V. A battery charged slowly at a rate of 13.8-14.1V may have a long life, but without a higher voltage finishing charge the battery will sulfate and the charge capacity will diminish with each charge cycle. Voltage in the 14.4-14.7V range allow a battery to charge faster, reach full capacity, and be less susceptible to sulfation. It will not charge as safely at high temperatures, and is subject to grid corrosion on the positive plate.

Smart battery chargers are much more sophisticated about charging a battery than a simple R/R, and will optimize the charging time, finishing rate, and float voltage. A R/R is a "dumb" device and suffices to keep the battery charged sufficiently under most conditions, but can't optimize battery charging. All R/R's when made are set to a maximum voltage output before they regulate the voltage. None are set as high as 15.5V, or even 15.0V for that matter. The fact that a manual deems a range of 14.0-15.5V as acceptable is more of an admission of poor quality control than anything else.

A charging rate of 15.5V will:

a. Boil the water from the electrolyte very quickly in a flooded battery (filler caps), exposing the plates. Exposed plates will quickly sulfate, thus the battery can suffer from both sulfation of the negative and corrosion of the positive plates, with a consequent loss of battery life.

b. Drastically reduce the life of bulbs, which are designed to work at nominal battery voltages but may be rated as high as 14.4V or so. Exceeding the design rating will always result in faster bulb burnout.

c. Not show the signs of overcharge abuse as quickly with a sealed AGM battery since the battery is sealed under pressure. Nevertheless, charging at 15.5V is way out of the safe range for this battery and its life will suffer accordingly.

The manuals say that the range of 14.0-15.5V is acceptable. 15.5V may be acceptable if the criterion is whether the bulbs blow immediately, but for not much else.

 

[shamer]

Well, the process I've been going through sure is proof that voltage drop is cumulative. Each time I've gone through connections & have a done a bit of cleaning I've incrementally improved my charging situation.

Tonight I went through & cleaned up quite a few grounds - I also added additional ground wires with 14 guage wire soldered to ring connectors and attached to bolts at the headlight and tailight areas. These met together at the negative side of the fuse panel (one of the small screws at the bottom). Does anyone see a problem with me having done this? In the past I've added redundant grounds to my other vehicles to keep all the wiring happier & avoid problems.

But, I still find myself with 15.2V at the battery! It was getting late & I didn't have a fully charged battery to start (12.5V), so I'm going to drive the bike to work tommorow (15 minute commute) and see what I get for a reading in a real world situation.

Thanks again, I'm slowly getting there\\/ ...