Modern Vespa

Hi there

Has anyone run across a wiring diagram that could aid with sorting this harness? It seems original given the presence of a green wire replacement outside the loom but the colors are off from the usual diagrams floating around. I also got service records with it going back several years for work at a reputable Vespa shop.

The multiple yellow wires are baffling.I can probably figure it out pretty easily working from the horncast and stator, but I was hoping someone might have seen this before.

From what I can see, it looks as if you have a later (1980 on) red-yellow stator with an earlier (1979 and before) double-yellow wiring harness. I can also see an external 12v AC regulator (little square box with yellow and black wires coming out of it) in the first picture hooked in parallel with your head light circuit (purple).
The head light coil on the later stator, purple (or gray in your case) wire, is stronger than the earlier ones. It sends current through a different regulator/rectifier (5-post) and caps the juice going to the headlamp so it won't burn out, hence the added 12VAC regulator on your system. Earlier regulator/rectifier, which you probably have (4-post) did not have the head lamp regulator circuit. The earlier stator sent juice straight to the head light unregulated, but was a tad dimmer.

The correct hookup should be yellow stator to yellow harness, red stator to yellow harness, (doesn't matter which yellow or red from the stator), purple stator to purple harness (with the yellow from the little square regulator spliced in). I can't seem to see a purple from your stator... might be faded or replaced to the gray colored wire. The yellow wire with the eye coming off of the blue CDI box goes to ground. There are a lot of yellow wires in your system!
Some wiring diagrams below.

Hope this helps.

http://scooterhelp.com/electrics/wiring/VSX1T.USA.after.pdf

http://scooterhelp.com/electrics/wiring/VSX1T.USA.before.pdf

http://www.vespamaintenance.com/elec/charger/index.html

Post 1979 stator with pre 1979 wiring harness? Then they used purple for a grey? Think grey out of stator is more common on PX.

Open up the 6 different possibilities via the link below and start compare/contrast.
https://www.scooterhelp.com/electrics/pages/VSX1T.p200.html

The purple tied to the yellow from bike harness is throwing me off.

Edit: old Poidog did a better job than me explaining.

I think you might be right Captcha about the gray lighting wire on the later PX stators. Good catch!

Thanks, everybody! I was beginning to think I'm crazy. This is an early 79 P200.

I've got a VBB1T with an early VIN that has similar issues...wiring and other bits that match 1950s scooters despite being a 61. Sometimes I think the factory (and service centers) just made do with what they had on hand.