The neutral switch mechanism on Ps
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Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Tue Feb 26, 2019 8:30 pm quote
Hi, I have a 1980 US spec P200E stateside, that has a "plug" that looks like this (I stole a pic from a topic here because I had none available):



I've installed cosa selectors bought in Europe on my other P2 and T5, but they look like this:



The switch thingy is missing, which, as I seem to recall, screwed into the white plastic part you can see on both mine and the first P2's selector box. But here's the thing: the protruding plastic part on my European Cosa selectors don't have a thread to screw anything into, and in any case, I wonder how a push button such as what's usually on the switch devices would work, as there seems to be nothing moving inside when I change gears that would press or depress the button when in neutral.

Pics taken for evidence:

Neutral:



3rd gear:



Anyone have an idea on how this is supposed to work? The only way to fit the switch seems to be to remove the white plastic part, but then I don't see what's going to operate the switch button, unless the copper tab actually moves outward at some point



Last edited by Frank N. Stein on Sun Mar 17, 2019 2:21 pm; edited 1 time in total
Hooked
GS160
Joined: 11 Jun 2014
Posts: 265
Location: Åland
Tue Feb 26, 2019 10:36 pm quote
Neutral switch

Seems to exist different types of switches, tho.
Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Wed Feb 27, 2019 6:26 am quote
Thanks for the link. Unfortunately, there's no evidence the switch system for smallies works the same as P-series bikes. The pics show that the switch plunger is depressed by the gear selector on the smallie, whereas on mine, shifting gears showed no movement of the copper tab against which I suppose the plunger would rest.

At first I thought maybe the system was set up as in Spanish Lambrettas, where a single wire goes to the casing, and the circuit closes with a ground in the casing itself. But connecting the live wire from the headset to the copper tab didn't work either.



If anyone has a working selector box with neutral switch laying around and doesn't mind unscrewing the switch and taking a few pics, that would be greatly appreciated, if only to see if there's anything missing or different in my setup..
Addicted
GL, PK, PE200
Joined: 24 Apr 2012
Posts: 642
Location: Deep in the heart of Texas
Wed Feb 27, 2019 9:41 am quote
I was confused with the neutral switch and finally just had to live with what I got. The neutral switch and the front brake switch looks the same but acts different. I got the front brake switch to work and I'm sticking with it.


The neutral switch when not pressed the light at the headset turns on. Turning the gears to 1st-4th will press the button and turn off the light.

http://www.scootermercato.com/Scooter-Parts/Switches/126938_2

The front brake light when not pressed, the light at the headset turns off. In neutral there's no light. Turning the gears to 1st-4th will press the button and turn on the light. This is what I'm using. No light, I'm in neutral. Turn gear, green light is on and go.

http://www.scootermercato.com/Scooter-Parts/Switches/126899

I have both and they just screw into the back of the gear selector with a washer. The one with the white tip is the neutral switch. I don't recall where I got it but it was too loose for the back of the gear selector but probably something I was doing wrong. The one with the black tip is the front brake switch. It fits better and I added the washer from the neutral switch and I'm using that. Its not a neutral light for me right now. It's in green in gear light now.

With all the things I had to do to get the scooter going, that was one of the least of my worries.

I hope that helps. Good Luck!

switches.jpg

Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Wed Feb 27, 2019 12:02 pm quote
That was super confusing. I get that you used a brake switch for your neutral light, and that it therefore acts in reverse from what it's designed to do: on when not in neutral; off when in neutral. But it also seems from what you're saying that neutral switch and brake switch act in the same manner: light on by default. The brake light turns on when the lever depresses the button, which by your description the neutral switch seems to do as well:
rowdyc wrote:
The neutral switch when not pressed the light at the headset turns on. Turning the gears to 1st-4th will press the button and turn off the light.
So I'm guessing the neutral switch in fact turns the light on when pressed, not the opposite?

Also, does the inside of your selector box opening look like the pic I posted? (the copper tab doesn't seem to move when shifting through the gears)
Addicted
GL, PK, PE200
Joined: 24 Apr 2012
Posts: 642
Location: Deep in the heart of Texas
Wed Feb 27, 2019 1:01 pm quote
Neutral light is on by default. While in neutral, the button sits in a small hole and not pressed. When gears are moved the button is pressed against a plastic piece and turn off the light. Using a test light on the switch will show you that pressing the button turns off the light.
My gear selector did not have the brass piece like your picture. May have fell out when I open motor two years ago and I may recall seeing a brass piece but lost through the years.

Btw, is that the old frame from the old neutral switch at the back of the gear selector? I don't see any threads to screw in a neutral switch. That piece should be screwed out before a new switch can go I there.
Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Wed Feb 27, 2019 1:30 pm quote
rowdyc wrote:
Neutral light is on by default. While in neutral, the button sits in a small hole and not pressed. When gears are moved the button is pressed against a plastic piece and turn off the light. Using a test light on the switch will show you that pressing the button turns off the light.
OK, so although they apparently have different shapes/references/diameters, both switches work the same way: they open the circuit (light turns off) when pressed. I wasn't sure from your previous wording.
rowdyc wrote:
My gear selector did not have the brass piece like your picture. May have fell out when I open motor two years ago and I may recall seeing a brass piece but lost through the years.
But do you see something moving when you change gears (neutral/others)? Mine doesn't seem to move in any way that would press a button if I could screw a switch in. Evidently that's how yours works. Ill try later to stick something in there (a Qtip probably) to see if there's any kind of motion I might not have picked up on from the pics.
rowdyc wrote:
Btw, is that the old frame from the old neutral switch at the back of the gear selector? I don't see any threads to screw in a neutral switch. That piece should be screwed out before a new switch can go I there.
That's how I got it (both, actually: a second-hand Piaggio off a Cosa, and a new FA Italia for Cosa as well). No thread, which is why I'm confused as to how I'm supposed to screw a switch in. I checked Cosa diagrams, and they seem to have a 2-wire system, which is why I'd expect them to be based on the older US spec selectors.
Addicted
GL, PK, PE200
Joined: 24 Apr 2012
Posts: 642
Location: Deep in the heart of Texas
Wed Feb 27, 2019 4:12 pm quote
I just realized the selector box you're using is not the same as the selector box for the US PE200 that I have. That box is made for EFL P series.

Looks like there was an improvement and the connector was added to the box and no need to screw anything in. Seems like it will only need the one wire connection you have hanging from the back. The US PE200 requires a 2 wire connection. Your's seems broke.



https://www.scooter-center.com/en/7676353/gear-selector-box-oem-quality-4-speed-vespa-px-since-1984-t5-125cc-cosa-10-series-with-idle-speed-indicator
Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Thu Feb 28, 2019 4:44 pm quote
That would make sense. I checked the wiring diagram for the Cosa, and there IS a single wire leading to the selector, with the ground apparently inside. The routing of the wire by the starter relay tells me a Cosa probably won't start electrically unless it's in neutral. Nice touch.



The only thing is that neither of my selectors work, and I've modified my loom according to the Cosa diagram: 12V to neutral light to selector.

I guess I'll have to check the connections again and see if the problem is with the selector or the rest of the wiring...
Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Sat Mar 02, 2019 2:57 pm quote
As suspected, the problem is with the selector. I pulled the wire, started the engine, touched the wire against the rotor cowling, and the neutral light went on in the headset. This is annoying, because both scoots are having the same trouble, and I have no idea what's wrong...

Since at least one of the selectors is new, I'm wondering if there's something missing in my setup; more specifically: something that would normally provide solid grounding.
Addicted
GL, PK, PE200
Joined: 24 Apr 2012
Posts: 642
Location: Deep in the heart of Texas
Sat Mar 02, 2019 4:06 pm quote
The wire is grounded by the brass circle piece inside the gear selector. You can see it in your picture above the shows the gear selector from rear. When in neutral only, the brass piece inside is pushed toward the wire and grounds the connection.

You don't have a connection at the gear selector for your neutral wire. The picture from Scooter Center has the correct connection on the gear selector. Does your other selector box look complete like the one from Scooter Center?

If you find a way to connect that neutral wire to the brass circle piece inside the gear selector the neutral light will come on. Or just ground the wire somewhere. It would probably stay on, too.

There's always the option of throwing money at it and buying a new correct selector box or find a good used one.

Good luck.
Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Sat Mar 02, 2019 5:40 pm quote
If you're referring to the copper tab with a hole in it, it's what you see in my pic; only mine was bent upwards when the pic was taken. But when testing the connection, the wire was plugged onto the tab seen, to no avail.

Both selector boxes look the same, and neither work. I'm starting to wonder if there's a feature in the Cosa setup that provides a ground that lacks when bolting the same box straight onto PX or T5 cases.

It doesn't seem obvious how the selector box manages to provide a ground when you look at it separately. The secondary drive connects to the box via an arm that doesn't seem to be very conductive. The rotating platter on top is steel on the other hand, and the cables might help. I'll have to check out if bridging the platter or other parts in the selector with a known ground (the cowling) does anything.



Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Tue Mar 05, 2019 3:29 pm quote
OK, so it seems I know why neither neutral senders were working. Well, sort of.

First, how the system works: the neutral light is grounded when both arrowed parts touch.





So I bent the pole-like thing outward a bit, cleaned the surfaces with WD40 on q-tips, and lightly sanded the contact surfaces, and the result was:



I don't know which of the bending, the scratching or the cleaning did it, but now that one works.

When I tried doing the same on the other selector, I noticed that the pole-like thing was missing, so it obviously wasn't going to work..

Anyway, I'm glad this has been sorted out, as it was annoying me to have set up both systems and have neither work, without even knowing why..
Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 319
Location: Paris, France & L.A., Cal, USA
Sun Mar 17, 2019 2:19 pm quote
As I needed to rebuild a second-hand selector box given me, I took some pics of the operating parts inside:





If anyone reading this rebuilds a US spec selector box, I'd be interested in seeing what they look like inside, namely the mechanism that presses the push-button.
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