Vespa Grande performance

XBrandon EdgeX /

I just bought a 1979 Vespa Grande and I can't seem to find any performance parts for it. Does anyone know if I can get an aftermarket carb or exhaust for it? Does Polini or Leo Vinci make something? I would imagine an exhaust for a ciao or any other vespa moped would work, but all I see is stuff for the scooters.

Re: Vespa Grande performance

I did a search on Vespa and found this post:

How to Make a Vespa Faster!

Author: Brian (---.NIPR.MIL)

Date: 06-08-01 18:56

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.

Hope this helps!!

Vespalad

Re: Vespa Grande performance

Thanks,Vespalad! I have the parts but have yet to DO the same exact mod on my Hero-Majestic ANKUR. B.J. at Handy Bikes had the parts I needed and treated me right on them.He sold me a #48 jet,so that sounds about right.

Re: Vespa Grande performance

XBrandon EdgeX /

Thanks a lot! I was thinking that the exhaust looked a little restrictive. The airbox has no screen in it, no plugs in the inlet holes, and a plug chop shows a golden brown, so I don't think I really need to mess with that too much. I don't want to cut the exhaust up on it, though. I'd rather find another used exhaust pipe to experiment with or get a polini if they're available.

I was thinking that since it's a variable ratio belt drive, that there was something I could do to the front pulley to make the top end ratio a little higher, like the clutch weight mod for the honda PA50 that was posted a while ago.

Re: Vespa Grande performance

You can get a top end kit from vespasupershop.com. They are the only place I've found that are a knowledgeable and reliable source of Vespa moped parts.

Do put the screen back in the air box. It is the only air filter the motor has.

I've seen one of those air boxes with the three "tubes" under the cover cut off. Since the tubes taper, I imagine it has something to do with the motor's operation.

Be sure you have the right air box too. The disc the screen sits against should have six holes.

Jim

Re: Vespa Grande performance

The inside of the airbox (under the screen) should have six holes in it. The version for the Ciao has three. The Grande uses a 49 jet in a Dell'Orto 12.12 carb. The Ciao uses a 43 in a 12.10 carb. Regarding the variator, I bought a Malossi performance variator (Malossi Multivar) for mine. It allows better acceleration by creating a smaller pulley diameter on the front and adds a very slight amount to the top end by creating a larger pulley on the front end at higher speed. It is also tuneable by buying different weights. Polini, LeoVinci and Sito all make exhausts which can be used on the Grande. You can use anything made for the Ciao or Bravo, since they mount exactly the same way. I use a Sito expansion chamber/exhaust which was actually made for the Ciao. It adds an easy 5 mph to the top end and the bike accelerates better because it is totally unrestricted. It is pretty loud, however. The exhaust, in my opinion, is the best way to get better top end. If you mess with the pulleys too much, you may also have to do a gearing change in the rear hub. If you really want it to run like gangbusters, buy a Polini cylinder kit and a performance exhaust. You will add plenty of speed and power. The risk, however, is that you will increase the engine rpms by more than 1000 and will rapidly accelerate engine wear.

Chris

Re: Vespa Grande performance

XBrandon EdgeX /

the airbox does have six holes where the screen should be, but the screen is missing in the airbox, also, the airbox hits the engine case on the left side of the bike (the case around the flywheel) so I'm not sure that it's the right box. It fits, though. do minarelli bikes use dellorto carbs? they look similar. would a screen from a minarelli work? also, where did you get your exhaust pipe and variator from, Chris?

Re: Vespa Grande performance

I got both the pipe and the variator off of eBay. They came out of Italy. I've seen some of the airboxes on dell'Orto carbs mounted upside down. They don't fit well on the Piaggio engine that way, however. Do you have it mounted with the three air tubes up or down? They should be up and it will fit. I can't answer your Minarelli question. Another thought about the posting above that mentions the 20, 25 and 30 mph versions of the Ciao. There is another major difference between the 20 mph version and the other two: it has different gearing in the rear hub to slow the bike down (14 to 1 wheel to pulley ratio compared to 8.5 to 1 for the faster bikes) and then has different size pulleys (the driven one and the clutch hub). You should really use the screen in the airbox, so that the air is filtered and so that the fuel/air mix is correct. They're not expensive and you can get a new one from Fabio at www.vespasupershop.com. He's a great guy, tell him Chris from Missouri sent you. He also sells Polini pipes and Malossi variators. I'm not sure whether he has them in stock for mopeds right now. Let me know if I can help further.

Chris

Re: Vespa Grande performance

XBrandon EdgeX /

I emailed vespa super shop about those parts and I haven't gotten a response yet.

Re: Vespa Grande performance

Yeah man, screw the Vespa supershop!!! I've been trying to call there for 2 weeks, every day its the same - before they open and after they close you get the machine, and when they are open the phone line is busy ALL DAY. It wouldn't be so bad if their website was finished and you could just order you parts from there, but there is no prices for half their stuff. It sucks. It's the only place in the country that (usually) has all the parts we need for Vespa mopeds, but it is impossible to get ahold of them (I too have unaswered emails from them, while my ciao waits for ten bucks worth of parts that I can't seem to get ordered).

BUT, on the other hand, when you DO get ahold of them, service is prompt and usually correct.

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