Modern Vespa

I've got an '81 p200e that I've been trying to get into reliable riding shape since picking it up a few months ago. The wiring harness was aging, so I started by replacing that with one from Scooterworks. Then I had the reg/rectifier replaced.

About that time it became clear that the stator wasn't charging the battery. I told a couple of the guys I ride with about the issues I was having and I heard a few suggestions to convert the p200 to a batteryless setup.

Before I start ordering parts, I want to land firmly on one option or the other and be convinced of why I'm making that decision. I was hoping for some input from the members to sway me one way or the other.

I've been told that batteryless will be more reliable but that I have better horn options and lighting if I keep the battery.

My goal is to keep the bike as simple and reliable as possible. I don't mind spending a little extra money to do this right, I just know that "right" could be subjective here. Thanks in advance for any comments/thoughts.

I mean ...reliable is sort of the wrong word.

Yes, a battery will get you bright horn and lights. It will also make your lights not flicker with rpm. But, it's one more thing you have to service on your bike, and that can be annoying. Also, if your battery dies on the road due to whatever reason ( broken rectifier, boiled all the water off, etc ) then you've got no / very weak lights.

So, it's a point of failure as well.


But, my wife's electronic ignition, 12v non battery lambretta is BLINDING bright, and no flicker. So... going non-battery doesn't necessarily mean you'll have weak or flickering lights. It's all a matter of what the stator puts out and what your wiring condition is.

Go non battery set up. I love it. Hate having to check the battery..charge it and all that BS.

drop the battery its dead weight .... then go an ickle faster

One other thing I forgot to ask, if I go batteryless would I need to change the wiring harness out?

In almost every case, yes. Not just that, but now your horn is DC, and it will need to be AC ...your brake switch often needs swapped out, and depending on your handlebar switches, they may need to be modified.

So... that's the RIGHT way to do it. THere's other folks who just throw a batt-pack eliminator ( which is just a big capacitor ) in there in place of the battery and leave it at that.

So, I'm hoping this thread develops into something good, I'll be watching intently.

My 79 P200 is a Euro Spec, meaning it doesn't have a battery, nor a Neutral Light. It does have a CDI, Indicators, etc, etc.

Before I rebuilt it, it was full of electrical gremlins, after rebuild, it still is. The wiring harness is old and frayed, I'm sure it's full of shorts.

Essentially I've got everything "working" except for the signals. Which I can live and drive without. But over this winter, I want to properly sort out the electrics.

I could not find a replacement harness, I called several shops. Plenty of US P wiring looms though. Also, I ordered new handlebar switches, but they are wired completely differentl from the original ones on my P (which are garbage too).

I had planned on starting a "how do I convert my P to a non battery" thread and just do that with my bike....

here's the wiring for your bike from scooterhelp.
http://scooterhelp.com/electrics/wiring/VSX1T.USA.after.pdf

and the one for no battery
http://scooterhelp.com/electrics/wiring/VSX1T.no.battery.pdf

options that I can see are:
1. remove the battery and ground the yellow wire. Your headlight would still be regulated (provided the purple wires go through the regulator) but the rest would be 12AC unregulated. Horn and signals would not work unless replaced with AC and a bit more on the signals.

2. the non-battery is confusing but I think if you got a non-battery regulator then you could connect the purple wires to have a non regulated headlight. remove the battery, ground the yellow wire and connect the red wire to the regulator where the diagram shows the yellow. Not sure what to do where the green wire goes into the regulator, on one path it seems to ground, and the other runs the brake lights and signals.

If it was me, I'd keep it stock and sort out the problems. It's not like it's a 74 150 super or something. The P200 had a strong working electrical system.

your switches are different from the US ones, try looking at SIP and maybe at some of the PK switches as well. I found a PK switch that was the same as an early 6v p150x. Most of the gremlins on the non-battery bikes are in the headset, so I'd start there.

Not to sound defeatist, but if replacing the wiring harness (again) is necessary to go batteryless, then that just about makes the decision for me. To me, losing a 'point of failure' as Eric called it isn't worth the pain that it was to get the harness up through that headset again.

I was a little puzzled at the strong push to lose the battery from the locals, it doesn't sound like it buys me all that much. Particularly if I'm rolling with one of those sealed gel batteries.

Great! I did find the ones I needed.

Yeah I think the P200E with-battery electrical system is pretty solid... if having a battery itself is the "major weak spot" I'm pretty happy. You can sort it out!

One other thing. Stators for the American p-series don't seem to be available anymore.

I've heard that with a PX stator (european?) and PX regulator all you have to do is wire it using one of the two yellow wires that run to the current regulator as the AC input, then wire the battery following the PX-150 wiring diagram for the new/post-95 PX.

Has this been done by anyone here before? Or is there a more effective way of dealing with getting the correct stator?

Thanks.