MOPED ARMY

Alright! Thanks for the reply.

That treatland.tv has a lot of parts, but every single one I wanted is out of stock, including the exhaust you recommended.

OK, so new list:

-Simonini Circuit exhaust

-Dellorto 13/13 Carb

-Malossi air filter

-malossi performance variator

-New belt/pulley

Also, I've seen a lot of posts involving "jets" or "jetting." What is that? Will I have to do that?

Thanks!

sorry I meant to say "it looks like they Don't have the Circuit in stock"

I'm sorry, I should pay more attention to what I am typing.

The Simnini Circuit is a good option. Better performance and is a few $$ cheaper priced than the Polini you mentioned getting from Zippy. But Treatland.tv is out of stock right now.

Here check out this other Post all about Vespa Exhaust :

http://www.mopedarmy.com/forums/discuss/7/121213/121213/

Hmmm, actually treatland.tv does have the Puch Proma Circuit in stock? Will that fit on my Grande?

So, Proma Circuit vs. Simonini Calibrata............thoughts?

Too many decisions!

That's what I thought. What about the Puch Proma Circuit? Would that be good for me?

I have basically the same setup and can hit 35 but I have the stock variator and wrong belt. I bored my carb out so it's not as good as a real 13.13. I have the techno circuit 2 and like it ok. it's not restricted like the original. You should be ok on the 66 jet that comes with the 13.13

Polini top one and Sp are good. Simo circuit interfered with my peddle sprocket, I can't hang with that, I'm keeping my pedals. I think its gonna take some porting and crank cutting to get the stock cylinder past forty.

Your Bravo is probably held back by that Polini pipe. There is no reason that setup should not be well above 40, especially on a light Bravo.

Ed, they do or did make a Proma Circuit for Vespa's. I have one sitting at the shop waiting to go on a Ciao, but I havent run it yet and don't know how good they are. I would go with the Simo Circuit, I think the Calibrata might be too aggressive for your stock cylinder, as was mentioned.

You will definitely need to rejet when you do this. This means swapping out the main jet in the carburetor for a larger or smaller one. This is crucial to tuning your moped correctly making it run right, and you must understand the how and why. I'm sure a small book has been written on it, but basically larger jets = more fuel, smaller ones = less fuel, which, given a constant volume of air, means richer or leaner fuel/air mixture, respectively. This mix is what is pumped into the combustion chamber, and affects engine temperature, carbon buildup, spark plug life, engine lubrication, and, when too far from ideal, can lead to engine failure, either because of a fouled plug that wont spark (not very bad) or a seized engine due to too much heat and not enough lube (very bad).

DCC: I agree with the that statement accept for vespa peds.

I have the 13/13, hi flow filter from treats, polini top one, a milled head, and am going to install my malossi multivar as soon as I get a belt.

Without the variator, You can expect like 34-36. Also a lot of this depends on what speed your bike was to start out with, but most of the grandes were the 30mph models so whatevs. Considering you are pretty green to small engines it seems, I would suggest just the pipe and the filter. The reason most people buy the 13/13 is because either they got one of the crappy 12:10 or 12:7 or 10:7 carbs stock. Grandes I believe have the 12:12, and considering the intake is only twelve millimeters, its kind of pointless.

A vespa intake can be bored out to 13mm and cutting the crank will help with mixture intake and exhaust duration, but thats varsity shit.

For my two cents, buy either the tecno circuit, the proma circuit, or if you have the cash, the polini top one. Then get whatever hi flow filter you can, and read about jetting ad plug chops. You will need to change the jet inside your carb, and its not hard. Also, search the performance section for "vespa variator mod" and you will find out how to get rid of the brass bushing in your variator that sucks.

Thanks friends!

and actually the vespa intake is just 10mm. or atleast that is what i have heard.

I just ground my brass bushing down, I know some people can push theres in, but not mine. You are right about the 10mm intake, sort of. The 20mph versions had the 10mm intake. I think the 25mph and 30mph versions had the 12mm intakes.

Also, Ed, get a new belt and install it. It got me a couple mph and helped my acceleration. They are like 15 bucks and chances are yours is like 30 years old, dried out, curled up and stretched out. Its one of those things that you don't really think about, but actually makes a big diff.

Also, turns out I have an extry high flow filter. If you want it I can sell it too you.

OK, This is going to be a marathon because I just got home from happy hour so... my apoilogies. Firstof all, most vespa engines have a 10mm intake. The 20mph versoins have a 6mm intake and a diffrent timed crank.

The polini long or country is actually a pretty good exaust with a variator. It gets a bad rap but I have 3 variated vespas including a Grande an it works better than you would expect. Of course, it's not on any of them at the moment but ..i still think it's a good pipe and a decent value. I have a Techno ciurcuit on a bike and it's OK. I have a Polini top one and it woks well but I don't know about $170 well. I have A Calibreta Simo pipe on the other and it destroys for the same price. if you are going to spend close to 200 bucks on a pipe, get the Calibreta and aside kick stand. Get what you can afford for now. If you really get into your moped, you can always upgrade later.

I think your problem is that the valve attached to your float is worn and leaking thus it floods your cylinder. That is why it ran great at first and won't run after it sits for a period and drains the tank. A new 13/13 carb will fix this problem. Get one and if you decide to drill out your intake (it's not that hard) you already have the bigger carb. Treats has a good deal on a carb, air filter, and throttle cable package. They also have a decent bolt on 64cc kit for $100.

Free speed upgrades are clean and repack your bearings, change your rear hub oil, pump up your tires, and make sure you have no brake drag. Look on the wiki and 1977 mopeds has a free vespa manual on their site. Learn how to work on your bike. It's not hard to do.

Having said all of that, I'm going to do an order from Europe next week and I'm going to order some Proma circuit pipes for vespa. I think they will be around $110 bucks or so. I have heard great things about them but I don't have one yet. If you want one, keep an eye on the buy sell forum in about 3 weeks.

Good luck on your bike and send me an email if you need help.

Tyson

iv'e already changed the rear hub oil, and checked for brake drag, but how do you repack bearings?

as for the manual, i have the vespa owner's manual for the grande, and the manual that went to vespa dealerships for assembly of the grande. i also have a ciao repair manual which gives a ton of great info. much more then the grande manuals i have give. just thought id share that.