Modern Vespa

We need help with wiring. The scooter is a 1980 Bajaj Chetak with original low use wiring that actually looks pretty darn good considering. This scooter came with almost all the bells and whistles a 1980 P200 had minus a turn signal indicator but it also came with points and 6 volts.

Looking at the Lavender colored wire going from the kill switch/Ignition switch, does this wire perform the same function as the green wire on the P200 which goes the the CDI to kill the engine?

If I am using the traditional P200 CDI would the lavender wire provide the engine kill circuit?

The stator in the picture above is non battery European PX 90 watt with a single power wire. I don't know how you can use it with a battery.
It seems the lavender wire is for the kill switch and prob the same as green on P.
That brown wire was connected to the fuse box from the key switch but you can run continuity check with a multimeter to verify.
What's your objective in updating the electrical system? Do you want to go 12v AC, or convert like a P with AC and DC?
You can try to use this non battery P diagram along with the Bajaj diagram to hook up the 12v stator without a battery but you will need a regulator and get rid of the diodes. You will need to change the bulbs, brake switch, and change or modify the handle switch to work with 12v vs 6v. If you keep the turn signals, a different flasher is needed.http://www.scooterhelp.com/electrics/wiring/VSX1T.no.battery.pdf

Thanks Rowdy that changed my thought process. The intention if possible maintain (as much as possible) the original wiring with battery and 12 volts. So far the only circuits I understand are the kill (LAVENDER) and the Neutral switch (BLACK/GREEN) leaving a WHITE wire a YELLOW wire and a pair of BLUE wires at the engine junction. Looks like YELLOW heads up to Key Switch, WHITE goes to the positive side of the Battery and the blue pairs go to the Diodes it seems. I do not know what this means.

Is there an alternative stator plate to support the Bajaj AC/DC system? What is needed for the regulator is the Vespa/Piaggio P200 type or the new small BGM type the best choice? Already have a new signal flasher.

I'm not familiar with the Baja motor and not sure what type of crank was used on them. Does the current P stator fit on the crank you have now? If so, you can try the P stator http://www.scootermercato.com/Scooter-Parts/Complete-Stators/186147.
The one in your picture above looks like this one. http://www.scootermercato.com/Scooter-Parts/Complete-Stators/217866

Bajaj has a 12v conversion if its the old type crank but that's a different animal easily found with a search. Of course the more expensive variable timing kits is an option for older cranks. Most just convert to AC without a battery using other methods.

I'm just recently getting a better idea of these old electric systems and someone may come along with proven options.

Left out the detail about the engine having 60mm with P taper crankshaft. Using the 1600g flywheel and a traditional electronic type stator plate. Wasn't necessarily looking to go variable ignition but if we need to shop for something more appropriate few extra pennies might not be so bad. Suggestions welcome.

[quote="hibbert" Looks like YELLOW heads up to Key Switch, WHITE goes to the positive side of the Battery and the blue pairs go to the Diodes it seems. I do not know what this means.[/quote]

I maybe wrong but YELLOW grounds when the key turns on so the stator can provide electricity. BLUE provide electricity to bike lights. In diagram goes to diodes but after conversion goes to regulator. WHITE maybe electricity from the battery but after conversion goes to regulator. This is all a semi uneducated guess as I've never worked on this type of electrical. Still not sure of all the components running off the battery. I would have to pull out the multimeter and run test.

Stay with the P electrics since you said you have the P crank.

I think there is a fair amount of DOT DC lighting in this scooter.

Here's my theory for connection.

With this stator http://www.scootermercato.com/Scooter-Parts/Complete-Stators/186147 and using this diagram http://www.scooterhelp.com/electrics/wiring/VSX1T.no.battery.pdf should get you close to what you want.

For spark: The stator's red, white, and green wires with single connection goes to the CDI. Lavender from wiring harness goes to green slot in CDI.

For Lights: The stator lighting wires are in the white multi-connector. Separate wires or hookup another multi connector with the correct wiring path.
The red wire from the stator connects to the WHITE wire from the harness and should go to the battery via a new fuse connection.
The blue wire from the stator is AC for headlights and goes to the BLUE wire from the harness. The BLUE wire should go to the regulator for AC power.
The yellow wire from the stator is unregulated AC into regulator for DC power out and should connect to the other BLUE wire.
The black from stator is ground.

Prob wrong but my head hurts after looking at diagrams. Somewhere the I think some wires should get spliced and re-connected. Someone that's done this should correct my theory.
There was a scootershop in the US that had an easy wiring harness connection for p motors in older bikes but can't remember who.

the wires from the PX Stator. The Red, White and Green go to the CDI.
The Violet wire from the kill switch goes to the other green terminal of the CDI

The black and blue wires from the PX Stator with the connector on the end go to the G, G terminals of a Vespa five terminal regulator.

The white wire which goes to the fuse block connects to the +B terminal of the Regulator.

The yellow wire connects to the C Terminal of the regulator. (The regulator also needs a terminal connected to the Chassis).

The Brown wire inside the panel with the diodes should be red and connects the Battery to the fuses.

Ignore the blue wires to the Diodes. They acted as a full wave rectifier in conjunction with the centre tapped magneto coil.

The brown wire in your hand in the photo below the PX stator looks like it connects to the chassis terminal crimp.

Thanks Rowdy and Worrywort!

Wow can I use a BGM 4 pin regulator?

Hello. Yes you can. Join the yellow and whit wires together.
The only risk is if you leave the lights on the battery will go flat.

If That was my scooter i would go all AC and leave the Battery on the shelf, along with my Sat Nav, Mobile phone, Kirby Trouser press and Lady-Shave,

darn it now I'm confused again. I do not plan to use any other devices what is a Kirby Trouser?

Why connect the AC and DC together? Seems AC in from stator (Blue/black) AC out (YELLOW harness) and DC out (WHITE) to battery.

I don't know why it's a good idea to change to all AC other than no battery. Is more alteration required to go full AC?

Nooooo. Not that yellow and white. The other ones.

Update: see my reply below. Sorry for the confusion.

O

Here in the US the headlights have to be on when the bike is running and AC is whats on US P series headlights so they don't stay on when bike is off. DC is used for the turn signals to make them work better. AC turn signals work OK but not a good as when they have a 12 volt DC current coming from the battery.

Hello.
Reading you post I assumed you wanted a 12V Battery on your scooter.

If you don't (And you obviously don't have a Kirby Trouser press). Then fit a simple regulator, AC Horn and Indicator relay.

Hello Mate. Let's step back and look at what we have here on the stator.

The old system has three circuits. The Ignition which has a coil, Points and condenser.

A second coil which feeds the lights via a yellow wire. ( I'm not going to include every item on the circuit as they're already wired together).

A Third coil with a Diode on each end and a White wire in the middle. This is an AC circuit which crudely converts AC to DC, for the Battery.

The PX Stator has two circuits. One has coils and a sensor dedicated to the Ignition.

The other one is an AC output which goes to the regulator. That's it.

The output from the regulator is split into two. The DC side +B goes to the Batter via the original white wire. The AC output from the regulator goes to the switch via the original yellow wire.

It's still the same in theory. Both have an independent ignition circuit.
The AC and DC circuits have been moved out from the stator to a regulator

Variable timing is always a very good idea with any tuned engine. If you went with a SIP Vape kit, it's very easy to wire up if you decide you want to go with full DC or all AC power.

Hello.
I have had another look at this thread and Think I should add this note.

If you wish to use the BGM regulator. Connect the white wire to the 12V battery connection and the yellow wire to the 12V out connection.

DO NOT connect the yellow wire to the stator directly as the old one did. The PX stator has a much higher output and MUST go to the regulator only

Sorry for the confusion.

As whodatschrome says the sip vape is an excellent bit of kit. I have it fitted on my engine.

made some progress on the wiring with the BGM regulator and standard P stator plate. Still need to get a battery connected but it appears all of the lighting is functioning on the AC. Have a question on the flasher, it comes with 3 spades, we have 2 wires to connect red/brown. Where do the wires go on the spades and is the 3rd for ground?

Where'd you get the flasher relay? Is that a 6V one? Might be easier to buy a 2 pin one from Motorsports.

I know on a P200 the 3 pin relays have one pin strictly dedicated to the indicator lamp. Look at a US spec V90/ Primavera and that has a 2 pin setup. Only difference is an extra wire going to the headset.

I got the flasher from Scooter Speed it says VF312-12V and DO NOT DROP. The picture does not show well the 3 spades are L, P and X. Maybe P for power L for Light and X for ground? Is Red P power source Brown signal switch L and Ground?

For a 12V P200 looking at a wiring diagram, X is power in from the regulator, L is to your switch and P is the indicator. The relay is just a pass through and the system grounds at the regulator and at the bulb.

Hello Hibbert
I asked around and that flasher is also used on old Japanese cars. It's a 12V Dc unit. X goes to the Battery. L goes to the Lamps and p goes to the pilot light on the Dashboard.

To answer your question Red goes to X. Brown goes to L.

If all the battery does is power your horn and Indicators, you could save money and weight by fitting a sealed lead acid battery like they use in Burglar alarms and Computers. 12V 2.5A will do the job fine.

Thanks guys haven't had a chance to test those connections just yet but another question came up. What size fuse should I use now with the 12V system?

Thanks again guys connected the flasher as worrywort said. Connected a small sealed 5 amp battery which fits nicely and 10 amp fuse. Tailight, rear brakelight, neutral light and blinkers all working with key ON engine not running. Front brake switch is not working at all?

Is it the switch or the wiring? I think the switch is the same as the neutral indicator switch.

If you touch the wires together do you get the brake light to turn on?

Need some help again with the wiring. Having trouble with rear brake switch and never got the front switch working.

I tried as MJRally suggested and touched the two wires at the front brake switch together, no brake light and did not pursue further until today.

After I got everything working the rear brake went out after a few miles not sure how many. Removed switch and it looked weird the spring inside turned white and black. It no longer plunged. I suspected a wiring issue.

Replaced the rear brake switch and after just a few miles same thing, no brake light, it's not plunging but it's more burnt inside this time. The plastic plunger thing totally got warm and deformed.

I do not know if I am doing something wrong but doing some trouble shooting on the neutral light I determined the neutral switch was intermittent. Then I tested the front brake switch which is the same as neutral switch and same as P200 and it seems the front brake switch is working good. It's a normally closed switch at rest it is opened when the brake is at rest and closes when brake is pulled.

Rear brake seems to operate same switch closes when rear brake pressed. When I touch the wires together at the rear brake switch the brake light goes ON.

No power at red and grey wires at front brake switch. 12VDC at red wire at rear brake switch.

Continuity at Red wire rear brake and Grey wire front brake

Continuty at Grey wire rear brake and Grey wire front brake

Couple of questions, what could be the cause of the rear brake switch apparently getting hot and going out?

Not sure what the continuity test means why is there no power at front brake switch? Is there something funny with red/rear and grey/front continuity? I chased the front switch wires they seem to go out of the headset down the center channel, not sure where they terminate no indication of them at rear brake.

Thanks I'm lost.