Is the new brush’s pig tail insulated or bare? Or is one of the other pig tails touching the housing? My two thoughts, any way....

Hello, Im new to the forum and been finding a lot of information here. Thank you. I have the same bike and have been able to kick started. Are the brushes only for electric start? As i mentioned I have been able to kick start it and it runs but then it takes for ever to start it again. I checked the brushes amd they are worn off one of them is missing the springs also.

It is also missing the timing plate and timing plate fixture. And when looking at your wires in the dynamo, it looks like some of my wires might be cross. Any help will be greatly appreciated.i will poat pics as soon as i can

Brushes are for starting & charging so kick starting you'd get a reasonable ride close to home with a fully charged battery & no charging happening. Looks like you have a bit to sort out there!!.

Thanks for your answer, this helps, even though it wasnt the answer I was hoping for lol

Anyone can tell me if the wiring look good? I have seen different versions of it. I am getting spark.

Also the dynamo is missing the timing fixture and timing plate but was able to set the timing and even turn it on, it ran good for a bit. Thanks in advance for your help. This forum has been awesome.

This is what you should have. Go to the tech library and look for a 125 parts list up to 76. Pretty much the same bike up to that point electrically. You’re missing a few part there, but you should be able to piece it back together. Peppy little suckers once you get it going. The 125s are a bit unique compared to the other bikes which are 6v systems. Due to being different, parts tend to be more available at a reasonable price. Good luck!

Hello Mandarrin , the color of the wires can help you to figure out where they connect. On the outside of your dynamo there should (hopefully) be some different colored rectangles.
The above picture shows how there is some variety throughout the years but the big pale green is from starter relay to start motor, orange is the ignition circuit (as mentioned above it’s totally independent of the starting and charging circuit) small dark green is a wire that the voltage regulator grounds to activate the charging circuit, and the white going to voltage regulator supply’s power generated it connects to both positive brushes and a wire from the starting coils.
Included a picture of my 1970 AT1 as the brushes were being replaced, two brushes are grounded to housing two connect to the white from voltage regulator.
The plate to set timing - if unable to purchase you could just bend up a piece of metal or stiff wire and attach so it came close to what they call the governor.

Thanks for all the help. I got new brushes and set it up like the pic you provided. It kick starts good but the electric start clicks or turns slow. Any ideas? Thanks.

If you put a meter on big pale green wire there should be close to 12 volts DC present when cranking, if voltage way low put meter directly on battery while cranking. If difference between the two locations is large then starter solenoid or wiring is suspect. Try removing spark plug it should spin over fast
The service manual in tech section shows how to test various parts of the dynamo / cleaning copper sections brushes contact, cleaning mica slots etc.

Will give this a try, thanks for all the help!

I havent tried checking the solenoid, I have a carb issue now.

I ran it and it was fouling the plugs, since I bought this used i order a carb rebuild kit. Anyone know what the standard main jet size is. The manual says 100 for the 125c and 140 for the 125a,b. The one on there now does not have a mark indicating the size. so how do I know which one?

Thanks in advance