check the yellow wire at the spade terminal and at the regulator, should be 14v ac max.

 

Cheers mate, have just checked that and I'm getting 35 volts through the yellow spade connector on tick over with the regulator plugged in and 65 when revved, does this mean the brand new regulator I have bought and fitted is not working ?? Or is something causing them to fail !!

 

Regulator is not working. Might be a broken wire.

Measure voltage on yellow wire into regulator and voltage on brown wire at regulator. Yellow should read same as other yellow, if not - the yellow has bad connection or broken.

Brown should be 0V, if not there is a broken brown or bad connection.

Was the regulator connector like new inside? It its dirty, chop the connector off and connect the wires direct.

 

Have now connected all the wires via new spade end connectors because the plug was all grotty and dirty, getting a readout of the yellow with red strip in, of 8volts at tick over when revved 14volts, the White is 0.80 volts, and the other one with two yellows into one is 12volts tick over and still 65volts when revved the earth is reading 0v at all times

 

Are you absolutely certain that brown is a good earth? Run another wire from that terminal to a good earth on the frame.

 

did you fix this I have 08 250 exc with same probs connector looks good and just spent £50 on new reg/rec and is exactly the same cant see any issues with wiring all i did was get an engine rebuild. Is it ok to use like this off road or will it effect the ecu?

cheers

 

It wont affect ECU.

There is a boken wire or its pulled out of the bunch of wires in the loom.

 

cheers kevtech just stripped the earth cable near the regulator and ran a separate cable and bolted that to the frame checked voltage at headlight and still about 14/15 idle and edging towards 60 with a rev. could it be something to do with the stator or is there a way to test the regulator? cheers

 

Thats weird. Are you doing these checks with the regulator bolted onto the frame? Not sure if it needs earthing.

The stator is OK, its making the volts..... its the regulator not trimming the volts.

 

tried it both ways will try stripping all the plastic covers off the loom tomorrow just to check

 

Alright mate nope still not fixed, it's driving me insane !!! Going to take that idea of an extra earth from it though !!! Then strip all the wires back !! And hopefully fix it, I have exact problem with the voltage you described !!!

 

Have you checked your stator at all? I don't know how but i'm convinced it might be something to do with it. Just because it was all fine before I removed my engine.

 

Got it - After hours stripping entire loom and testing all the connections I finally noticed a broken connection on the stator coil looks like the solder had just vibrated off or something soldered it up and hey presto all lights working fine popped sown to halfords and replaced my rear leds and all running fine now. Anyone interested in a almost new reg/rec?

 

hi mate having the same problem with my 250 exc 09 tried everything except stator what should i look 4 tks

 

Hi There, I have the very same issue with my brothers 300 EXC-E, measuring 60V AC at the output of the rec/reg, which we have just replaced. Cannot find any other obvious signs of issue, will check stator when time allows. Did you have to remove any coatings/coverings to access the damage mentioned?
Thanks for your help in advance.
Am I also correct in thinking I have brown=Earth, Yell and Red = +12V from battery, white=AC in from stator and the yellow is regulated output feeding lights etc...
I can't believe that this is the reg/rec faulty again.

 

Problem solved on my brothers bike. stripped stator out of casing and had a really good poke about, could not get a resistance reading from white wire. found the copper wire had snapped off right at the solder joint, invisible until I moved the red/black one from on top AND pressed the wire with a screwdriver. Had to scrape some of the laquer off of the wire to tin and soldered a second piece of wire along side to prevent further snappage.
Resistances of stator wiring should be as follows:
Red to green (pick up coil) approx 100 Ohms, a magnet or screwdriver passed over ot should vary it a little
Red/white to Black/white (Coil going to CDI) reading 14.5 Ohms
Yellow to earth on stator read very low 0.6 Ohm and once repaired, white measured the same. white to yellow read around 0.8 Ohms when repaired.
I have photos to support but it seems I can only upload from a URL, let me know if there is another way.:scooter:
Hope this helps, quite an easy fix in the end