• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Flat battery - why?

  • Thread starter Thread starter Guest
  • Start date Start date
One other thing I would check, since you do not have a clamp on current meter (I'm assuming) you can use your vom and the parasitic resistance of your harness to confirm the system is pushing current to the battery.

The R/R (+) output should always be higher voltage than the (+) battery at anything above 2000 RPM. If it is not then the battery is discharging. This will be something in the range of 0.25V to 0.5V or as high as 0.75V with poor connections at 5000 RPM. Confirm your meter indicates negative voltages when you reverse the leads. Negative means discharge when measuring Red to R/R (+) and Black to (+) battery.

This may be a better indication of what is going on. Something is apparently changing while you are ridding. Could be a thermally induced break in your stator cause it to stop outputting when it gets hot. Could also be a temp sensitivity of the R/R I guess.

If the voltage does anything wacky during riding you will likely have to dive in to charging. I'll stop guessing now.;)
 
Last edited:
Voltmeter

Voltmeter

I used electrical tape to fasten my round 2 inch troubleshooting voltmeter to my handlebars. Incidentally there is a very handy place to connect to 12 volts. Most bikes have ignition voltage to one side of the horn and the horn button then grounds the other side. Find out which of the connectors is 12 volts. You can just slide a bare wire into the spade connector. Quick and dirty is sometimes best.
 
this may or may not be helpful, but i had a similar problem last year. it turned out actually to be my starter clutch. i know how stupid that sounds, but bear with me.

the bike wouldn't start, at times, after riding for a while. one of the magnet cups the magnet broke off of, and the puck that caught the shaft when the starter was engaged to turn the motor off could move around freely. sometimes, when i stopped, it was at the top, and seemed to drop down into the clutch area and jam it. so the starter wouldn't even work. just a click. all the lights were fine, fuses good, battery voltage checked out fine. confused the hell out of me for weeks. I'd get ****ed, walk away from the bike for a few mins, and then come back, hop on, roll it off the center stand, and it'd start fine, because the puck would make it's way back into the proper area.

so, i guess my question is. when you got it jumped by the car, did you roll it before you tried it?

sorry for the long story, just wanted you to know where i was comming from.
 
this may or may not be helpful, but i had a similar problem last year. it turned out actually to be my starter clutch. i know how stupid that sounds, but bear with me.

the bike wouldn't start, at times, after riding for a while. one of the magnet cups the magnet broke off of, and the puck that caught the shaft when the starter was engaged to turn the motor off could move around freely. sometimes, when i stopped, it was at the top, and seemed to drop down into the clutch area and jam it. so the starter wouldn't even work. just a click. all the lights were fine, fuses good, battery voltage checked out fine. confused the hell out of me for weeks. I'd get ****ed, walk away from the bike for a few mins, and then come back, hop on, roll it off the center stand, and it'd start fine, because the puck would make it's way back into the proper area.

so, i guess my question is. when you got it jumped by the car, did you roll it before you tried it?

sorry for the long story, just wanted you to know where i was comming from.

I hope we are not guaging the battery health by how well the motor starts :( . Too much to go wrong to use that as a battery test; apparently the battery is going flat Right PsyGuy????
 
I hope we are not guaging the battery health by how well the motor starts :( . Too much to go wrong to use that as a battery test; apparently the battery is going flat Right PsyGuy????
not so much gauging the health of the battery as having a perfectly good battery that sometimes won't work. i'm just sharing my story incase it may ring true for this situation. i skimmed through the thread, but i admit i didn't read all of it. i didn't notice anything regarding the battery being tested as dead, but rather just acting like it's dead, which is what mine was doing at the time as well. if i missed him saying the battery was verified as totally dead, i am sorry. not trying to add any confusion.:|
 
not so much gauging the health of the battery as having a perfectly good battery that sometimes won't work. i'm just sharing my story incase it may ring true for this situation. i skimmed through the thread, but i admit i didn't read all of it. i didn't notice anything regarding the battery being tested as dead, but rather just acting like it's dead, which is what mine was doing at the time as well. if i missed him saying the battery was verified as totally dead, i am sorry. not trying to add any confusion.:|

Well I'm not sure he verifed the voltage either, he simply said the lights dimmed. That would happen if there was a mechanical block and the starter sucked a bunch of current and pulled the voltage down. Seuader, it is interesting this can occur and appear to be a dead battery ; I'm hoping PsyGuy was not fooled by this situation and he really has a flat battery. Else wise I'm chasing my tail. :-&

Probably the simplest test that will give you a good indication of battery state is to measure the voltage at 12.8V with bike OFF and then turn ON the ignition (so the coils are energized) and see how far that pulls the battery down (simple load test) ; should be about 12.5V. This is a health battery and relatively controlled test.

If that doesn't work, you either have bad coils or bad battery.
 
Last edited:
thanks guys.
the battery was definitely flat as the headlight was dim with just the ignition ON (no cranking). i did not confirm the actual voltage but the bike started right up with the jumper cables, without moving the bike at all.

Something is apparently changing while you are ridding. Could be a thermally induced break in your stator cause it to stop outputting when it gets hot. Could also be a temp sensitivity of the R/R I guess.

this is an interesting idea. i think the problem may be happening on an on/off basis - i've ridden numerous times with no problems whatsoever, but the battery did go flat on two ocassions - while the ride circumstances stayed all the same (time, mileage, temperature, etc,).

having a vom connected while riding to see if there are any anomalies seems like the most sensible thing to do.

i'll report back when i have some data.

thanks everyone


ps. i'll go get some aligator clips for my vom, sounds like a handy little thingy :o
 
thanks guys.
the battery was definitely flat as the headlight was dim with just the ignition ON (no cranking). i did not confirm the actual voltage but the bike started right up with the jumper cables, without moving the bike at all.



this is an interesting idea. i think the problem may be happening on an on/off basis - i've ridden numerous times with no problems whatsoever, but the battery did go flat on two ocassions - while the ride circumstances stayed all the same (time, mileage, temperature, etc,).

having a vom connected while riding to see if there are any anomalies seems like the most sensible thing to do.

i'll report back when i have some data.

thanks everyone


ps. i'll go get some aligator clips for my vom, sounds like a handy little thingy :o
oh hell yes they are. sometimes you need more than two hands, a couple clips on the ends of your leads and you are business!
 
I suggest putting a volt meter on the battery while on the bike and ridding it. It can't discharge is you have over 13.0 volts on the battery ridding.

so, bought some aligator clips for my VOM, put them accros the batt + and - , and went riding today - voltage tested at a steady 5000 rpm:
  • new battery
  • 13.1V fresh off the charger and holds charge
  • while riding with the HEADLIGHT OFF - charging at 14.7V
  • with the HEADLIGHT ON, the voltage immediately dropped to 13.7V and then slowly kept dropping to 12.2V (it took an hour to drop this far)
  • after turning the HEADLIGHT OFF AGAIN - charging at 13.1V and slowly goin up (after another hour or so) to 14.6V
 
psyguy,
It looks like you are charging, but drawing more amps than your stator can provide. It could likely be a schenario of one phase not putting out any juice. The most likely culprit would be the stator and I suggest that you disconnect it and test for 80V AC (at 5000 RPM) between the three legs, they should all be similar.

If all is OK there I would give the R/R another look.
Keep well.
 
psyguy,
It looks like you are charging, but drawing more amps than your stator can provide. It could likely be a schenario of one phase not putting out any juice. The most likely culprit would be the stator and I suggest that you disconnect it and test for 80V AC (at 5000 RPM) between the three legs, they should all be similar.

If all is OK there I would give the R/R another look.
Keep well.

I agree with Matchless that your are not getting enough juice out of the stator. The R/R is regulating, but as you continue to run the voltage continues to drop below any level that is capable of charging the battery.

When you switch the light on and the voltage drops to 13.7V that is a big drop in and of itself but there is still enough to charge a battery (above about 12.8V or so.) However if that resistance were to increase with temperature, it would be sufficient to quell the output of the charging system.

It is clear that the charging sysyetm is not working Refer to Phase A Step 2 of the revised stator pages. You probably will pass this when cold but progressively fail as you run due to some heating.

http://www.thegsresources.com/_forum/showthread.php?t=143019

http://www.posplayr.100megsfree3.com/FH012AA_Charging/Stator_Papers_Phase%20A.pdf


I suggested before directly measuring the voltage difference between R/R (+) and Battery (+) at 5000 RPM as you ride. If that voltage is more than 0.25V-0.5V then you have connection problems. Run a direct fused wire between R/R (+) and Battery (+) to confirm that you can get that voltage low.

This will save you from a stator swap and additional running around.
 
Last edited:
Some of these bikes have the 3rd phase routed through the front controls and it's only engaged when the headlight is on. Check those connections to make sure they aren't goobered up.
 
+1 on the overdraw.

Tell us about your headlight. What bulb? Did you modify or "upgrade" bulb or light?

Could be high resistance switch, harness, connectors to headlight.

Keep following the other advice above. I'm trying to think of anything not mentioned.

- JC

I think what is being discussed is an inability to deliver the required load, not so much an overload. The stator cannot put out rated load due to either:

A.) temperature sensitive breakdown in the stator windings
or
B.) temperature sensitive poor connections (some where)

The suggested measurements will provide the answer.
 
If the only thing that was going on here was that the headlamps was 100 watt instead of 55 wats and the battery voltage drops to 13.8V when the lights are on then there is another problem. There is nothing to suggest to me that that type of load would be the problem.

13.8V is sufficient to charge a battery as it is more than a volt above the battery internal voltage (e.g. 12.8v) Something else is causing a drop in battery voltage as that battery is charging at 13.8V.

Your presumption is that the battery charge is decaying from 13.8vv down to 12.2v due to cumulative loss of charge due to excess draw. That can not be the explaination for the problem in that anything above 12.8v represents charge flowing to the battery. If charge is flowing to the battery the voltage cant go down. There is something else going on as I described.

[/LIST]If he's running, say, a 100w headlight instead of a 55w (or whatever the limit), the above could happen. Overdraw, overheat wires, further overdraw.

Headlight off=okay
Headlight on=drain
Headlight back off= okay again

By all means test the other stuff, but it makes sense to check the circuit that is possibly triggering the problem, too.

- JC
 
My experience has been, considering R/R, wiring/connections, stock lights all being standard and working, it usually is the stator being partially short circuit on the windings and may show some visual burning on one or more phases, usually only the outer layers of the windings. Getting about 25V Ac instead of the 80V at 5000 RPM is an indication. Heat may or not play a role here and the short circuit may not be present with the stator cold and come on when the wire expands.
The resistance test of the windings is too inaccurate to use and an "Low Insulation" 500v/1000V tester may show it up, but only if it shorts to ground. Partial winding short circuit is hard to measure when you always have 6 x 2 poles in series and the total resistance is less than 1 ohm.
I suggest checking the stator output when cold and hot.

Just for info:
Rewinding with heavier wire has its limitations as the amount of wire layers and turns you can get on each pole are usually less. The actual limitation is the distance that the poles are apart at the bottom and the length of these. It is possible to get 80V AC with heavier wire, but you need to wind it absolutely perfect with each winding properly squared against the previous, so that no space is wasted. This can only be done with some skill and experience. The beauty of such a rewind is that you start charging significantly at lower RPM's and show a positive charge even while driving very slowly in traffic.
Aftermarket stators may be wound with less copper or using thinner wire and then covered with a coloured resin making it difficult to see and are not necessary bullet proof. The resin and the type of enamel used on the copper wire is also part of the longevity of the stator.
 
Matchless,
I agree with your assessment but would only add, that since we appear to be dealing with a temperature sensitivity we need to conduct the stator pages voltage measurements with that in mind.

It is not conclusive that the stator is the issue and it would be unfortunate to swap it out when in-fact it is a temperature sensitive connection else where that is causing the R/R to regulate improperly.

If Psyguy can verify all the steps in Phase A of the revised stator pages, and have good connections but low output when hot then it is much more likely to be a bad insulations in the stator.
Jim

My experience has been, considering R/R, wiring/connections, stock lights all being standard and working, it usually is the stator being partially short circuit on the windings and may show some visual burning on one or more phases, usually only the outer layers of the windings. Getting about 25V Ac instead of the 80V at 5000 RPM is an indication. Heat may or not play a role here and the short circuit may not be present with the stator cold and come on when the wire expands.
The resistance test of the windings is too inaccurate to use and an "Low Insulation" 500v/1000V tester may show it up, but only if it shorts to ground. Partial winding short circuit is hard to measure when you always have 6 x 2 poles in series and the total resistance is less than 1 ohm.
I suggest checking the stator output when cold and hot.

Just for info: Rewinding with heavier wire has its limitations as the amount of wire layers and turns you can get on each pole are usually less. The actual limitation is the distance that the poles are apart at the bottom and the length of these. It is possible to get 80V AC with heavier wire, but you need to wind it absolutely perfect with each winding properly squared against the previous, so that no space is wasted. This can only be done with some skill and experience. The beauty of such a rewind is that you start charging significantly at lower RPM's and show a positive charge even while driving very slowly in traffic.
Aftermarket stators may be wound with less copper or using thinner wire and then covered with a coloured resin making it difficult to see and are not necessary bullet proof. The resin and the type of enamel used on the copper wire is also part of the longevity of the stator.
 
thanks guys.

  • the headlight is standard 55w, no mods.
  • the rr is honda model with the sense wire and the rr +/- are connected directly to the battery
i'll check the stator output when cold and hot.

however, my bet is on the following:

Some of these bikes have the 3rd phase routed through the front controls and it's only engaged when the headlight is on. Check those connections to make sure they aren't goobered up.
 
ok, done some more testing.

warmed up the engine and tested the stator:
  • voltage on all three legs reads upwards of 80V.
  • however, when i connected one leg through the headlight switch, on the return wire that goes to the rr i get no signal (no voltage) :eek:
so, would you recommend to connect all three phases directly to the rr (that has a sense wire) or to try trace the problem in the stator-headlight circuit?

if you could tell me the pros and cons of both options that'd be great as i'm keen to learn more about the electrics :o
 
Run all three stator wires straight to the R/R. Keep the headlight on. (safer anyways) Problem solved.
 
Back
Top