Modern Vespa

I want to fit an LED headlight on my P200E. What must I do to get DC power for the LED?

The easiest way would be to open the HI-LOW beam switch and identify the feed wire to the headlight (should be the one NOT colored purple or brown- I think it is either yellow or white for your bike). Find the other end of that wire at the junction box under the front of the horn cast, disconnect it and tape its end.

The next step is to solder a short jumper wire from the horn button feed solder joint to the headlight wire on the HI-LOW switch.
Then choose an LED headlight bulb that fits.

Voila'! And if you need to return it to the stock set up, all you have to do is snip the jumper wire in the switch and reconnect the original headlight wire in the horn cast.

Not sure if the SA models are the same as American spec battery models, but if they are, you could run a jumper off any of the white wires. White is key switched DC and you can avoid the handlebar switch.

If I look at the wiring diagram of a PX Vespa, the supply to the switch, and from there to the horn, comes from the C connection on a 5-pin voltage regulator. Since it is a DC horn, this supply must be DC?

So it looks as if I must replace my voltage regulator with a 5-pin regulator and run a wire from there to the light switch (grey connection) and from there to the
LED headlight. (I am not just replacing the globe, I am fitting the SIP headlight 57268300).

Do you guys agree?

First, let's clarify if you have a P200e or a PX200? What year?

P200E 1980

Thanks- look here for a better wiring diagram. PX is a totally different beast.

http://www.scooterhelp.com/electrics/pages/VSX1T.p200.html

Just looking at the wiring diagram, I'd say disconnect the purple wires at the junction box behind the horn cast, and build a jumper from the purple handlebar wire to the white wire at the horn. That should feed the handlebar switch DC and you don't have to try and cram anything else into the headset.

PHOTOS... WE LOVE PHOTOS of whatever thingee you are talking about.

What about a bridge rectifier?

I'm thinking about doing something similar, looking forward to seeing what route you take & what works.