Modern Vespa

I have an early p and the harness has the following colored wires for the stator. 2xyellow, 1xgreen, 1xblack, 1xpurple.

I am putting together a motor and I am going to need a stator soon. Which stator is the easiest to adapt to this harness? The bike has a battery but no electric start.

You are wanting a new stator for the SAME scoot which used the double yellow? The EASIEST thing would be to fix your double-yellow you have, or find another double-yellow for replacement. Otherwise, if you want to use a single-yellow stator (much easier to find) you'll have to alter your harness is my understanding.

1977-79 Ps (serial pre-34627) have stator plates with a 1A or 1B stamped on the back, a mostly unobtainable 4-pole regulator, an unobtainable 4-pole keyswitch, and a speedo in mph only. Off the stator plate you'll have double-yellow wires to the regulator, purple to the headlight, black to ground, and red/white/green to the CDI. The tail- and brakelights will only work when a battery is in the frame.

1980-82 Ps (serial post-34627) have stator plates with a 2A or 2B stamped on the back, a 5-pole regulator, an 8-pole keyswitch, and a speedo in both mph and kph. Off the stator plate you'll have yellow & purple wires to the regulator, red to the battery, black to ground, and red/white/green to the CDI. The tail- and brakelights will work off of the magneto.

Perhaps there's a hack on the BBS about rewiring a single yellow to work on a double-yellow setup... I've seen a number of discussions about the two stators there. But the path of least resistance would be to stay double yellow I think.

I don't have the stator. the bike had no motor when I got it but it has everything else. I am having a hard time finding a double yellow stator which is why I was looking for a way around it.

Ahah. I think I've seen some discussion of rewiring the single-yellow to work on a double-yellow harness on the BBS. It might be best to just upgrade the harness to the more modern single-yellow, but that would be more work and expense of course.

I found what I was looking for. A nice neat way to adapt a single yellow stator to a double yellow harness.

Thanks for the replies.

Sweet! If it's not too much trouble you should post it here. I am sure someone will have the same problem some day.

I have the same problem. Sorry, I know this is an old thread, but I need the help. I have double yellow frame with a motor (I installed) that has a single out with black ground and red/white/green to CDI. I can't seem to find any writeup on how to convert the single wire stator to the double wire(yellow) regulator so I can run my lights and charge the battery.

Thanks for any help in advance!!!

My understanding is that to convert a single yellow stator to a double yellow, you need to 'float the ground'.

If you look closely at a single yellow stator and trace the yellow wire back to it's source, you will see that it is wound to form a series of coils and then is grounded to the plate of the stator. Detach the wire from where it is ground at the stator plate, insulate it and extend this end of the wire with yellow wire of the same gauge as the original yellow. Now you have a double yellow stator, with each wire carrying half-wave AC.

I think I'm right, but if not, please someone else correct me.

I have read about that before, but I think I might just buy a new harness and be done with it. It seems that the double yellow stators are not easy to find as the singles like mine are.

Thanks everyone for the input.