How to Make a Vespa Faster!

Being stuck with a Sluggish Vespa myself, I started the research and tinkering and here's what I found. The Vespa Caio's came in 3 different speed rated models from the factory, a 20mph model (the one I unknowingly bought), the 25 model , and a 30 mph model. After talking to the techs the difference between the peds is in 3 different areas. The Exhaust, The Air Restrictor attached to the Carb, and the Jet in the Carb.

After tweaking the Exhuast on mine; cutting it open gutting it and welding it back together again; My top end went from 20 to 24 mph. Next I changed the timing; this is done by changing the gap on the points. Factory calls for .016 setting, I gapped mine at .020. The wider gap advanced the timing and improved performance; again my top end increased to about 26-27 mph.

Next the big step, Tuesday my new jets will come in, it was a pain finding a supplier but I found one. The stock jet is a .043 and requires the air restrictor to be attached for the moped to run properly (Limiting the air and fuel the ped gets so limiting the power it can acheive). The jet I ordered a .049 does not need the air restrictor. With the new Jet and the Air Restrictor removed (the small plastic box attached to the carb) I should get about 35+ mph with no problem.

Re: How to Make a Vespa Faster!

Don't run too long with the unrestricted exhaust without changing the jet. You can easily seize the motor.

The restrictor in the air filter is the plastic disc behind the filter element. Ciaos use one with three holes. The Grande with a 12mm carb and .049 main jet uses a six hole restrictor.


Re: How to Make a Vespa Faster!

Thanks for the heads up. I bought the ped for my nephew, unfortunately I found myself enjoying buzzing around on the little thing, so it will be a little dificult to separate with it next week. Hopefully he will enjoy the ped, if not I have no complaints keeping it for my own use.

Re: How to Make a Vespa Faster!

Three years and 1400 miles later, I say the same thing about my Grande, which I bought to fix up and sell. Glad I didn't!

The Ciao also came as a "Super Deluxe" or some such name that also included a variator and turn signals. Don't know what size carb or type of exhaust it used, but a variator in my opinion iis the way to go.


Re: How to Make a Vespa Faster!

This particular model is the Supreme. It has all of the electrical goodies but not the variable belt drive. The funny thing is, all my buddies where teasing me something severe when they heard about me buying a moped, but at the campground they where all lining up to take turns riding it. Heck not even my Honda Magna got that much attention.

I am thinking that I should probably detune it before I give it to my nephew. Let him get use to it for month, then upgrade the topend speed from 20 mph to 35 mph. After all how much speed should a 14 yr old have on their first bike?

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