FZR 400 CHARGING ISSUE

[boxter99]

Hi,
FZR 400 1WG 3EN1 1988. It has a three face (3-cable) stator/coil which seem to measure ok with an omometer. Also I can fire the engine up and measure AC Voltage output on the faces starts from 15-16 Volts AC at iddle and when revving it goes up to 57-59 Volts AC. But when connecting the regulator/rectifier (the ones that mounts into the frame under the fuel tank, it has 4 pins) the DC output is 1 Volts DC. The peculiar thing is that DC output is about 2-3-4 Volts DC at idle but when revving the engine drops!!! to 0.92 Volts DC.
So i thought it was faulty regulator and i ve change it from another 3EN1 FZR (used one from Ebay) but again same thing. Nowhere near 12-13V DC output. So then I thought that all these regulators are crap (since they are really aged) and got a brand new one from Hong Kong for 15 quid. Same thing!
I am at a loss... Anyone has seen this? Any advise?

Regards,

[boxter99]

Hello,
I have an update, if anyone has seen something peculiar like this please respond:
I ve changed the coils/stator and put stator from another FZR400 and also the magneto. I dont know if they were working, the donor bike used to work fine but I didnt test it with a voltometer back then to make 100% sure and now has no carbs on it to do it. So i took stator and magneto from that bike to my bike. But the stator is measuring ok resistance wise and its windings look just fine (no burns etc). Still have the same issue. I have now connected a R1 regulator the 3-way cable from the coils going directly to the R1 regulator and the output of the regulator goes just to a voltometer. So the whole FZR400 loom is irrelevant (in case it had some sort of shortage).
When revving to 3000-4000 rps the regulator's output even with the other set of coils reads 0.98 Volts DC. But... what i ve noticed is that if we play with the idle to drop the revs to the point that the engine will stop completely, close to that point (engine going slower to ... stop) the voltage starts raising to normal levels 7-8-9-10 Volts DC as it should! Its very peculiar! I.e. with less revs it produces the DC voltage. I dont know what i am missing here...

Regards,

[Evilchicken0]

To be honest I don't know.

How much voltage do you get across the battery terminals when the motor is running and revved ?

[boxter99]

To be honest I don't know.

How much voltage do you get across the battery terminals when the motor is running and revved ?

Thanks for the reply. Yeah thats a good question, I am looking just that at the moment, i.e. if the battery is acting as a capacitor because the voltage when revving is pulsating and without a good battery i wont be able to measure it properly. I will update when i have a new battery because i think its impossible to be faulty stator. I have 3 FZR400 motors in parts and one in a bike and it just cannt be all bad.
Mean while I would be very greatful if any good soul from here could disconnect the 3-way connector from the stator (1WG or 3TJ would do) and measure with a voltometer the AC voltage. As, the resistance measurement that suggests the factory manual is not really a good troubleshooting point. I would like to know what is the AC voltage reading when the engine starts (in idle or little more) and then revved to 4000 rpms.

Kind Regards,

[Evilchicken0]

You could be overcomplicating this. The battery charged and ready should be about 13v with the engine running it should be about 14.5v, when you rev it it shouldn't go much higher. If it spikes up to 16v then the reg rec is duff.
Charge the battery and leave it for a few days, if it doesn't hold the charge then it's the battery.
Check the earth on the battery is tight on both ends



As you can see the charging circuit is quite simple, it's either the battery, regrec, genny or the wires between them.

[boxter99]

As you can see the charging circuit is quite simple, it's either the battery, regrec, genny or the wires between them.

Exactly mate, I know so I have swapped stators, swapped even magneto's, swap several 4-pin rectifiers even used one with 5 pins from R1/R6 and still same. Of course I checked the loom cables and in the end I even replace them with my own "mini" loom. Therefore I am thinking, as I am sure that the regulators are not all duff, that its either that all my stators faulty (possible but i dont think/hope so) or the batterry acts as a capacitor in the whole circuit to allow the 13v to be measured correctly and my battery is f**ed.
Now if someone kindly measures the AC ouput voltage that a healty FZR 400 stator produces with a voltometer (set to AC ~ 200Volts) both on idle and around 4000 rpms I would know for sure.

Regards,