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Molto Verboso
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
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Location: Tucson, AZ
 
Molto Verboso
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71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
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Here is some feedback. I purchased this P200E last week. It is a P200E (American) with the battery wiring. The battery was dead but I put a new one. The voltage regulator was a Chinese aftermarket one so I went and replace it with a 4 pole aftermarket unit that scooterwest sells(in lieu of the Ducati one yellow, purple, pink., etc)

The stator is a double yellow wire. Here is the problem, the headlight is still dim, very dim, it gets slightly better whenever I rev but like I said, slightly better.

I put thesame headlight on my other P200e and is bright. I also connected the same head light to a 12volts DC battery source and is very bright.

The stator seems to work great, the motor is starting on the first or second kick and all the electrical system works well except the headlight.

Would you please direct me at some basic T-shooting tips. The wire that comes from the stator that suppose to source the head light comes out of the stator as a blue wire and it mates a purple wire.

What should I be looking next? I have a digital multimeter and I can take some readings. Could it be just one single coil on the stator going bad? That would explain that the engine still runs great but the little coil inside the stator that feeds the headlight might be bad.

I have the HAYNES owners workshop manual but it doesn't really show a specific way to Tshoot . Any help would be appreciated
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Vespa lxv 125 vie dell moda Chianti
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Addicted
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Vespa lxv 125 vie dell moda Chianti
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What voltage are you getting out of the stator to the bulb, if not 12 volt then the problem is there
@aviator47 avatar
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2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
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@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
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If the tail light comes on good and bright when you turn the headlight on, that pretty much rules out the stator, and suggests a problem in just the headlamp circuit. You can check the voltage at the regulator input and 12 VAC output terminals to verify this.

If you are getting proper voltage in the above checks, then I'd begin by checking voltage at the input (not ground) terminal to the headlamp. If it's 12V or higher, that would suggest a poor ground. If less than 12 V, then the problem is probably between the switch and the headlamp.
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Hooked
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Hooked
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Aviator47 wrote:
If the tail light comes on good and bright when you turn the headlight on, that pretty much rules out the stator, and suggests a problem in just the headlamp circuit.
Not necessarily, on the double yellow stator only the headlight is AC, fed by it's own coils. The rest of the machine is DC.
Unplug the stator blue (should be purple?) from the junction box and connect a 12v headlight lamp between this and earth. This will tell you if the fault is in the stator (lamp dim) or wiring (lamp now bright).
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Molto Verboso
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Molto Verboso
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You could swap flywheels and see if it gets brighter.
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1974 Rally 200, 1974 Rally 200 with sidecar, Vespacross bike
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1974 Rally 200, 1974 Rally 200 with sidecar, Vespacross bike
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Does your other bike use a double yellow stator or does it use a red/yellow?
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Molto Verboso
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
 
Molto Verboso
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71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
UTC quote
Gasmk1 wrote:
What voltage are you getting out of the stator to the bulb, if not 12 volt then the problem is there
I put the DMM and I am reading a fluctuation between 7 volts to about 9.5 volts at idle and it goes to 20 plus some volts when I rev up.

My other P also read the same
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Molto Verboso
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
 
Molto Verboso
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71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
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Mattgyver wrote:
Does your other bike use a double yellow stator or does it use a red/yellow?
Actually it was originally a double yellow wire but I am looking at it right now and it a red-yellow connecting to a yellow yellow.
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Molto Verboso
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
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Posts: 1614
Location: Tucson, AZ
 
Molto Verboso
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71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
UTC quote
Well, after messing around I think that the headlight is much brighter now with the new voltage regulator. It gets brighter when I rev but it is much dimer than my other P 200.

I think that part of the reason is because I am running a stella headlight with a true halogen bulb on my other P and it gets very bright.

As off right now, I am reading 7.5vac to 9.5 vac at idle on both p 200 headlight connections and both can reach well over 30 VAC whenever I give a good rev. I think I am going to go ahead and order a Stella headlight.

My question now is : why in the hell Vespa engineers didn't want to run the unregulated purple wire that goes to the headlight and run it through the voltage regulator first?
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Molto Verboso
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
 
Molto Verboso
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71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1614
Location: Tucson, AZ
UTC quote
So I kept Tshooting and even with simple test I still can't figure out. My last test was the test that I did yesterday which was putting a 3 prone H4 halogen light to my "good p200", this thing lits up brightly. Output at the plug when the engine is rev peaks over 30 vac and around 8 to 9.5 vac at idle.

Plugged the same H4 halogen 3 prone light o the other "bad vespa" and this thing can't even lit up but the connector gets the same voltage.

Could it be that the stator flunks whenever it gets a load (I am talking about just the blue/purple wire coming from the stator).

I took a look at the switch and it seems in to be in great condition. I am thinking about making a 5 or 10 minutes video showing all the 10 plus test that I have done.. Please help!

I am willing to run the headlight directly from the battery if that is what it takes to ride with a normal light. At least the battery gets some charge.
@aviator47 avatar
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2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
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Location: Paros Island, Greece
 
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@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
UTC quote
If you are getting correct voltage at the headlamp socket, but no weak illumination, take the bulb out of the socket and check the ground connection for that socket with the ohm meter function. One lead on the socket's ground terminal and the other on a good ground. Should be close to zero. If it is showing high resistance, you have a bad ground.
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Molto Verboso
Joined: UTC
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Location: NC, USA
 
Molto Verboso
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Location: NC, USA
UTC quote
firekdp wrote:
Aviator47 wrote:
If the tail light comes on good and bright when you turn the headlight on, that pretty much rules out the stator, and suggests a problem in just the headlamp circuit.
Not necessarily, on the double yellow stator only the headlight is AC, fed by it's own coils. The rest of the machine is DC.
Unplug the stator blue (should be purple?) from the junction box and connect a 12v headlight lamp between this and earth. This will tell you if the fault is in the stator (lamp dim) or wiring (lamp now bright).
^^^^^^^^^^ Do that. A bulb is both a voltmeter and ammeter (wattmeter). Like a stator version of a battery load tester. Separate the stator wire at the engine junction box and hold it to one of the tits on the bulb. Hold the base of the bulb against engine metal. It should glow brightly.

If not, insufficient stator output. Weak magnets can cause yellow illumination of a 30 watt bulb, but still provide spark and proper engine running. Swapping flywheels from a bright light engine verifies magnetism. An 1157 brake/taillight bulb has about 20 watts brake, 5 watt tail. Using that, revving up should blow or be blinding. Playing around will give you approximate total output wattage.

The blue wire that should be purple may indicate a rewire due to a past problem. If the stator flunks the load (bulb) test, stator/wiring inspection time.

Vespa engineers did run the purple wire through the regulator on the 5 wire regulator red/yellow system. The double yellow unregulated AC type works fine and removes the regulator (possible problem) from the headlight circuit.
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