Modern Vespa

Hi folks!
Been posting replies in another thread, but thought it might be getting a bit off the original topic, so......

I've got a 1979 P200 (early one) with a bad regulator (4-wire; must be made of unobtainium!) Tested at the headlight socket, and got about 20V at idle, and revving it up nearly pegged the meter on a 50v AC scale....

So what's a scooterist to do? Are there alternatives to replacing the (nearly impossible to find) regulator with one of the same type? Can the 5-wire type be used? They seem to be a lot more common....

Also, this scooter's been fitted with a reed valve and Malossi carb (it's a 30), but it looks like the air bellows won't reach the horn it's supposed to hook onto.... and there's no air filter, either... this bothers me more than a little.... What do folks do in this kind of situation? Are there air filters that would fill the gap?

Thanks for any assistance anybody can offer!

Joe

Definitely sounds like you've got a bad regulator.

We do have new ones for sale. They're not the original style, but we've modified them to fit and plug right in.

Give a call if you'd like to go this route.

Thanks for the reply, and the good service on the phone, Max!
I Forgot to address the other issues: Air bellows ,which says "Malossi" on it, appears to be too short to reach from the carb to the body... Is there some technique involved here? Should I be able to stretch it that far (about an inch or so)? Additionally, there's no air filter on the carb.... Is there a better solution than duct tape and foam rubber? Thanks!!

Yeah, the air bellow takes a little stretching to attach to the body (and it can be annoying to get fully attached when there). You should look for a real air filter - I bet that foam rubber is more restrictive than the real filter would be (the real filter is kind of just several layers of wire grating)

Thanks for the reply!
Would it be acceptable to just stick an air filter on the carb (assuming one can be found), and forget about the bellows? Will the air flow under the cowl be sufficient?

Joe

It'll work fine off the frame, mine was running fine like that for a while because my bellows were shot. Technically, it might have BETTER air flow, because if your bellows are attached to the frame it can only suck air through the hole in the frame. But if it is not attached to the frame then air can come to it down through the frame but also under the cowl. The problem is you're more liable to get water and dust and crap coming up into the filter from the road than down through the hole in the frame. I think long-term you'll want the bellows attached.

the bellow serves as a clean, COOL air supply

the air under the cowl is to hot for the carb to operate properly, imho

the air from the frame is cooler and plentyfull

always run with the proper equipment

+1 - I can't imagine why the bellow won't reach. And if it doesn't... you should probably get a new one

Thanks, folks!
So are there others on here with the Malossi setup on P200's? What do you do for an air filter?

the malossi carb i had(never installed)had a bellow that fit the p

http://www.scooterwest.com/items/?_pageCCS=t#page=/item_details/Malossi-30mm-Carb-Kit-w-Rotary-Manifold/2363

that is the bellow you want, no need for filter, you could throw some k+ n foam in the bellow if you wanted

Oops! Sorry jimmyb865! Should have mentioned that it's got a reed valve, not the original rotary.... Bet that makes a difference!

not really, same bellow i believe

call max at motorsport/scooters west and ask if he has a articulated bellow for the malossi carb-reed/rotary

Ok, so back to the electrical issue... Replacement regulator (and headlight assembly, by the way) arrived today, all plug-n-play, no problem there, everything fit just as it should, but.... 20 seconds after starting the scooter, the headlighht blows again! Now what? I've heard of a "clipper diode" that is somehow supposed to shunt everything over 13V to ground, but it seems like addressing the symptom, rather than the cause... Anybody got any ideas as to what I might check next? Where to measure, and what to expect? I'm in the dark (in more ways than one!)...

Joe

I talked with my mechanic and he said to regulate your headlight circuit with an inline regulator or clipper diode.

ok, so here's what I know: There's a 3-prong connector on the back of the headlight with black, brown & green wires going to it. I have surmised that the black wire is common, the green is high-beam, and the brown is low-beam. Measuring between the brown-black and the green-black pairs with nothing connected to the connector (except the test leads, of course!) gives similar results on both circuits - about 13-14 at idle, and around 22 "at speed"....

Will I need to put a clipper diode in both the green and the brown wires? How does it connect? Is there some place I can introduce the clipper diode that will protect both circuits?

Thanks for your help!!

Joe

from what i remember that aint right

everything up front should be 12volt

horn, bulbs, ect

check that the two violet wires are not crssed at the rectifier
http://www.scooterhelp.com/electrics/wiring/VSX1T.USA.after.pdf

Thanks, JimmyB, but my regulator has only one violet wire, one pink., and 2 yellow going to it (originally, anyhow - Now the violet's taped off, and then regulator's been replaced with one from Max that doesn't use the violet wire... I'm assuming there's no difference between the 2 yellow ones.. doesn't matter which one goes on which terminal on the regulator?

Thanks again,

Joe

give me a minute...............

You want to put the clipper diode on the headlight wire going to the headlight switch, so that the both the high beam and the low beam wires coming out of the switch are regulated.

yes

your lamp is powered straight from the lighting coil

Ok, thanks, guys! I found (in the junction box on the engine) where the purple wires are joined from the stator to the wire that ultimately goes to the headlight switch, providing juice to either the low-beam or high-beam light... Measured there, and got the same too-high readings I'd gotten elsewhere, so... that's where the diode goes, I reckon....

Yellow wire teed into the purple wire? Black wire to ground? And I guess with a longer screw, I could just mount the diode itself on top of the junction box...

On to other mysteries.... Is the taillight supposed to be on without the scooter running? Trying to figure out which is taillight and which is brake light... The one that comes on with the switch is the one with the white wire going to it (took it apart to see... ) ...

Thanks again for sharing your experience with an old fart who's been away from Vespas for 20 years, and suffers from CRS...

Joe

Just checked, and the front brake-light switch is working fine, just the back one's not doing anything...

Okay, progress! Both brake-light switches are working now! Amazing what 25 years in a basement will do to electrical contacts! Now all that remains to getting it ready to ride is the headlight issue! Am I really just one clipper diode away from having a functional scooter?!?!? Cool!

yes

and like max said is how it should be wired

and get it to fit under the headset

what is a clipper diode?

This site has good diagrams. The difference seems to be the two yellow wire stator type regulator vs the other regulator that has the "A" terminals that seems to provide the AC clipping for the headlight via the purple wire.

Notice the purple wire feeds to the switch, then to the headlamp on the earlier model without going through the regulator. It seems it was designed for the stator coil to not overload the lamp without regulation, as on the old balanced systems.

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

If your Vespa has this unregulated headlamp stator output, then a clipper from the purple wire to ground should work. Since the output is AC, it takes two Zener diodes in series or a special package. If your headlight blows, all the stator output goes through the Zeners to ground. That is equal to or greater than your headlamp wattage, and that generates a good bit of heat. They would need to be sized accordingly. The two Zeners tied together are at the bottom of this page. You could make it from lower wattage Zeners, and just keep a spare in case they blew. A single Zener would be seen as a short to ground during one half cycle.

http://www.allaboutcircuits.com/vol_3/chpt_3/11.html

A simpler fix might be to install a series voltage dropping resistor in the purple wire. It would make for a dimmer headlamp at idle, but keep the voltage down at higher rpms. Your scoot may not have the original stator with the appropriate lighting coil for the unregulated system.

You could install behind the engine cowl, tapping into the purple wire at the junction box.

I use Electronics Distributing, on Brookstown Ave for electronic parts. I live about 30 miles west of you.

It's a device that, according to what I've been hearing, prevents over-voltage in a circuit; in this case, the headlights...Not real clear on the "how" of it, but they seem to work, where the actual regulator fails...

Anyhow, I'm gonna try one in my headlight ciruit to see if that will prevent headlight blowing, which, thus far, has been 3 times, all within seconds after installation....

Good luck!

Joe

Thanks, BlackBart! I work about 3 blocks from Electronics Distributing, so maybe I'll drop by and see what they recommend...

30 miles? would that put you in the Statesville area?

Hi again folks! I've seen many references to the scooterhelp.com wiring diagrams, but found them too small for my old eyes... here's a link to another site that has a larger, and to my eyes, clearer diagram for my early P200.... http://24.101.58.15:8080/schematic/p200e_1.pdf

Hope it helps others with old eyes!

Joe

if you click on the diagram and then use your zoom tool it is great, my eyes are shot too

the other site will do as well

JoeP833, I'm in west Yadkin.

Thanks, Max!! Got the clipper today, installed it, and all is well! Measured about 10v at the headlight socket, which makes plenty of light for my purposes, and no blown bulbs anymore! I'm a happy camper!

Joe