Thank you both for your advice, I surely appreciate it. One thing's for sure, the person who least knows about the issue is me so any and every advice is welcome. I'm really not all that confident with Baja's reply since they have a reputation of mixing stuff sometimes so I'm gonna play safe and clean the stator's housing, if there is supposed to be oil in the case then somehow it'll flow back in again, if it doesn't then I'll be safe too...

 

Thank you both for your advice, I surely appreciate it. One thing's for sure, the person who least knows about the issue is me so any and every advice is welcome. I'm really not all that confident with Baja's reply since they have a reputation of mixing stuff sometimes so I'm gonna play safe and clean the stator's housing, if there is supposed to be oil in the case then somehow it'll flow back in again, if it doesn't then I'll be safe too...

 

Hi Lynn, finally I was able to test the wires with a voltage meter, here are my findings:

1. There are two yellow wires comming from the stator to the regulator, each one measured 10 volts.
2. Ran the engine at fast clip and the voltage at the battery terminals starts to drain from 12.7 to about 12.2 instead of increasing to about 13.5 as you indicated.
3. Measured the voltage directly at the red wire on the regulator which is supposed to feed the battery and it outputs only 9 volts at idle and fast clip.

any tips????

 

The wiring diagram I have for the Baja 250 shows only two wires from the stator for the battery charge winding. Usually 250cc engines have a three phase charging system that would require three yellow wires from the stator. Other posts have indicated that their Baja 250cc quads have three wires - even though the wiring diagram says there is only two. I had always assumed the wiring diagram was just wrong, but maybe there really is a single phase version of the charging system similar to the 150cc GY6 engines as well as the more typical 3 phase system.

Can you post a pic of your stator wires and regulator?

Also, was the voltage you measured (10 volts AC) measured between the two yellow wires, or between each and ground? Was this measured at cranking speeds, idle, or at a fast clip? Was this voltage measured with the regulator unplugged, or was the regulator hooked up while doing this?

 

Yes, it was kinda akward to me but it does have only 2 wires going from the stator to the reg/rect, one wire is yellow and the other one is pink.

The 10 volts that I mentioned in my previous post were measured between each of the stator wires and ground and not between the two wires themself. I turned the engine at both fast clip and idle however the 10 volts remained constant all the time....... Here's the wire diagram that I got from Baja Motorsports and also a picture of my stator. I almost forgot, the regulator/rectifier was plugged in during my testing...

 

Your regulator is exactly the same as mine (150cc GY6 engine), your stator is classic single phase GY6 engine style, and your wiring diagram of the baja 250 is exactly the same as mine (which has always been wrong so far on other 250cc bajas - but clearly is correct in your case). My regulator fifth wire drives the auto choke instead of the fans. There are six wire versions of that regulator that drive a fan and an autochoke.

Unfortunately stator battery charge winding voltages measured while the regulator is hooked up are meaningless. This is because the regulator is a black box that takes widely varying AC voltages in, and makes constant DC voltage out. There are many ways to do this, and all of them involve severely yanking the stator output voltages around. And the different designs do it differently. So any measured voltages will involve too many unknowns: What design scheme (series buck versus parallel shunt)? Is the voltage low because the regulator is yanking too hard, or is the stator too weak? Who knows - these are meaningless data points.

On your quad measure the stator charge winding output voltage between the two yellow wire (not to ground) with the regulator disconnected. At cranking speeds (with the kill switch on to prevent idle and higher speeds) you should get 9-10 volts AC. Cranking speed is roughly 600 RPM. The output voltage should be roughly proportional to engine speed, so expect three times higher at idle (1800 RPM).

Then make sure the battery and ground connections are hooked up and then you're down to a bad regulator.

 

Today I tried two different regulators to see if the required voltage was getting to the battery in order to charge it and I got the same results as with my factory regulator so it gets down to the stator. I was checking on ebay and since it just costs $17 I bought it. Can't wait to get my hands on it to bolt it on and see if the problem is finally solved. All my wiring is new, the battery is new, the reg/rect is new, and now the stator will be new.

Is there any other component involved in the process of generating power and getting it to the accessories and batteries that could prevent charge from getting to the batt once I bolt on the new stator???

And by the way Lynn, thank you so much for all your help... really, It would've been impossible for me to pinpoint the source of the problem without all the info you have provided so far...

Here's a shot of my ride...

 

For $17 I'd just try a new stator too.

As far as other things that could keep the battey charge circuitry from working:

Wiring, and multiple bad (or incompatible) parts leading to wrong conclusions, and garden paths.

Let's hope the stator works. Let us know how it comes out, and if it doesn't work out just remember I like challenges .

 

I just installed the new stator and voltage between the two yellow wires is about 20 at idle and goes over 40 at fast clip so I guess that's acceptable. The regulator is outputting 14.6 volts constant at idle and fast clip however when I connect the red wire to the battery, the voltage falls to 12.1 at idle and barely rises to 12.8 at fast clip... Correct me if I'm wrong but I believe it should rise to about 14 volts when the engine revs up, so Im guessing there is still something not working correctly, but, what could it be????

 

I belive I've found the reason why my ATV is not charging the battery... The CDI on my ATV is a DC-CDI which means it runs on battery power. While the rectifier may be flowing sufficient battery charging power, the CDI on the other hand keeps draining it at the same time therefore ther is never sufficient volts going into the battery in order to charge it. The question is, is there a regulator/rectifier that can produce a larger amount of voltage to supply both the DC-CDI and charge the battery at the same time???