Modern Vespa

Hi guys, so from what I've read on et2s, stock restricted ones go around 30mph. I've upgraded the carb to the 17.5. And on flat ground I can go about 33mph, downhill about 37mph. Does that mean that I have the restricter in the cvt? And is there anything in the cdi I have to change to go faster?

Definitely no restrictor in the CDI. Don't remember if there's a spacer in the variator or restrictor in the exhaust. If there are, you're definitely not going to get much more speed wise.

I read that replacing the exhaust with a performance one adds a few mph. But my carborator is from California so there is no air-fuel mix screw. It's stuck in the tune its in, so would the aftermarket exhaust mess up how the bike is tuned or would it be ok?

Yes on a two stroke motor like the ET2, an exhaust will make some difference. Itll accelerate better and allow the motor to rev out higher. Be aware that even brand new racing exhausts can sometime come with the restrictor cone installed. Legal reasons probably!

As far as the carb, yes you should adjust it every time you change things. The air/ fuel screw, the needle and then the main jet. Since your carb does not have an air/ fuel screw, you may need to swap idle jets. Dont get hung up on the carb coming from California, that means nothing.

For now, I'd start getting your hands dirty and open up the bottom of the carb and figure out what you have jetting and needle wise (theres little numbers stamped into it) as well as look for a restrictor in the exhaust/ variator. With everything removed, best case you'll get 40 mph. Anything higher, and you'll need to swap to race parts.

That seems a bit slow, are you talking about gps mph or speedo mph, there is a 3-4mph difference.
Upgrading the carb to a 17.5 on a standard et2 won't make it any faster Imho.
I have an ET2 (PHVA 12) and 2 LX50's (2T PHVA 17.5) and they are the same, they will hit 45mph on the speedo on the flat.
On the ET2 I have added a Sito original pro exhaust and a Malossi variator and it's a bit quicker, enough to make a few more mph on the steep hills so it works for me.
If you change the exhaust you will have to put lighter rollers in as the exhausts are designed to give more power at a higher RPM. Without this it will feel slower pulling way then you will feel the difference over 30mph.

If I were you I would try and sort out what you have first.
If it has a spacer, it will be on under where the belt goes. If your belt is worn this will have the same effect so worth checking that.
Your carb should have at least a 60 jet in it, check that.
The exhaust might have a restriction on it, depending on what exhaust it is that can be different.

Top speed wise without changing the gearing the only way to go faster is higher revs.

Thank you for the replies. My numbers are mph GPS. Speedo doesn't work lol. When I got the bike I noticed that it had its factory tires from 2001 so I'm suspecting that everything is factory, including the belt. I'll change it this weekend and look for the washer. I don't think the exhaust as a restricter because to change the tires I had to remove it and I didn't see anything in it.

It's my first bike so I'm just worried that if I change something like the exhaust and I didn't do something right in the carborator that I could destroy the bike. That's why I'm so worried about not having a air/fuel screw. Changing the idle jet would work to keep it properly tuned without the screw?

I need to change the fuel petcock so ill check what jets I have when I start taking the bike apart for that

The main jet is the thing you need to get right as that's controlling the fuel at full throttle.
I haven't changed the idle jet and the mixture screw is still more or less factory position. If the main jet is a 60 or 62 it should be fine.
(The lx50 2T restricted comes with a 53 here)
The simplest way to spot an issue is you will feel it loose a bit of power at higher throttle if the jet is not right.


If it's had no servicing for years check your foam air filter is good as they disintegrate over time. I'm assuming you have the standard air box or the jet would need to be much bigger and even then it probably won't run right.

It's got a new filter and the rubber bit and manifold because they were all ruined when I first got the bike. I feel this. But right now I suspect it's my vacuum line and the petcock. The vacuum line says windshield washer fluid on it so im thinking under full throttle it's closing because it's not a proper vacuum line. If a proper line doesn't fix it than ill definitely look into bigger jet. Is there anything else I need to change when I change the jet or is it just the jet and it's good?

Some people change the needle for fine tuning , that is for the throttle mid range. The standard needle should work fine on your set up though.

So I changed the oil belt and the drive belt today and unfortunately no difference in speed even more unfortunate was there was no sign of a restricter. Sadly I think 33 mph is all it's got in it without modifications:/

Sounds about right. Also depends on the headwinds, your weight, the roads etc. etc.. Vespas are probably middle of the road speed wise. Yamahas and Hondas being the slowest to accelerate and top speed, Genuine/ PGO Buddy's being the quickest.

If you want to make this faster, its pretty easy and parts are relatively cheap. Another $600 in parts and you can break into the mid 40's.

Your speed does seem low. As said before, there are a lot of variables to consider.

My 2003 all stock ET2 can do 40 pretty easy and a lot of times between 40 and 45. That is going by the scooter's speedo so not sure how accurate it is.

Don't rule out simple things like tire pressure. When you lift up a wheel, either end, do they turn fairly easy?

I just changed the tires so they are good, and yes they turn pretty easy. I know my petcock is kind of sketchy, would that be slowing me down?

If that's your suspicion, I'd test it with a bypass. Here is how I did it when I was troubleshooting my recent issue. Be sure to give it a breather hole on the opposite end of the bottle you use.

I'll be "hot rodding" my ET2 this fall, once it's no longer 115°...I found LOTS of great info on YouTube...check the Piaggio Zip 50 upgrade vids on SCOOTER STREET (he's assured me it will ALL work on my ET2) and check Two Stroke J's channel, too. There's lots of "go fast" ET2 vids online.

Lots of Malossi 70cc stuff and Malossi exhaust, jetting/reeding carbs, variator weights, etc.

Victor

Victor,

Give Stage6 a look as well. They make some fantastic go-fast parts for Piaggio HiPER2 engines. I have an '05 Typhoon that will be getting "the treatment" soon too.

For the exhaust, I'd recommend either a Yasuni R or a Yasuni C10. They're a touch pricey, but worth it for the performance.

I built an '07 Genuine Buddy 50 with a Stage6 Mk.II Sport kit and a Yasuni C10 pipe. Wit a 21mm carburetor, it can wheelie on the low end and still hit 65mph.

This makes no sense. What sort of carburetor is it? Did you buy it used? Dellorto doesn't make a version of their carb without an air fuel screw. I can't think of anyone who makes a replacement carb for any two stroke that doesn't have an air fuel screw. And once you go off idle, the air fuel screw doesn't do anything anyway. It sounds like you're overjetted, because if it was too lean, you would likely be wondering why it's suddenly going 50mph.

Motovista's answer makes sense to me...and I ain't a wrencher! I live in Cali, own (only) 2 Vespas, 1 an ET2, and I know those Dellorto carbs can be tweaked, contrary to what I've been reading. I'm about to un-restrict my ET2 exhaust, rejet the carb, and other fun stuff this winter. I don't expect a whole lotta problems, based on the dozens of hours of videos I've watched from places -- and from Vespa riders -- all 'round the world.

But I could be wrong. Hell, I've been wrong before!

when you say you looked at the exhaust for a restrictor, which end did you look in?

as been noted, there's no restriction in the CDI. there is in the CVT, but the spacer there is fairly apparent.

33mph sounds about right if the tuning is off on the carb, the intake system isn't ideal and the motor is tired. or weigh more than about 180lb

When people talk about a restricted 50cc scooter, it's either been restricted to go less than 20 or 30 mph, depending on the moped law in the State where it was first sold. If you have the MSO, the horsepower rating on restricted bikes is always under 2 hp, because that's also part of the law that caused them to be restricted in certain markets. California was never a liquor sickel state, so you don't encounter restricted scooters sold new there. If it's a California bike, and it goes faster than 30, it might need to be tuned, but it's not restricted. And if you find the same site I did many years ago, where they show you how to cut into the CDI to derestrict one of the Piaggio models, don't do it. I did. Then I replaced the CDI so the bike would run again.

Gotcha! Thanks for the clarification for a California boy, Motovista.

V.

I looked on the side that goes into the engine.

I was there when California changed the law and classified 50cc mopeds as motorcycles. That probably is one of the key reasons scooters never took off in the US. Before that, you could buy a Motobecane or Sachs moped from Sears or Monkey Wards and turn your teenager loose on it.