Hello to all: This is my first post and I hope you will excuse my english. I am from Sevilla, Spain, and I drive a Vespa PX 200 E 1995 to work every day: I need more power. I have a Polini cylinder kit (140.0082) and a Polini exhaust. The question is: what else do I need to make it run perfect? No engine porting modifications, same carburator. Do I need a new head? Will a head gasket ( 1,5 mm) do it? Timing 18º'? What jets do I need? etc. Thank to all of you, and excuse me for been so telegram-writing.
Thanks, I am expecting your answers.
Hi, you need to move the timming to IT' about 18-17 degrees,get the head done[:)] leave the fourth gear as a p200 as the polini will easily pull this (malossi's need T5, they need to rev's)
match the ports in the crankcase,cut the crank, clean and match the inlet(don't open too much)
jetting, start at 125 and work down
run it in well, as this kit has weak pistons
fine but you will loose your autolube mate.
malossi manifold and a 28 or 30mm delorto carb 
30mm has definitley bigger venturi so youll have more air to go in so more fuel mix to burn so more power but of course more gulp! gulp! hope this helps.
Thak you, I was thinking no body new .... well, thanks a lot.
Wat do you think about the head, or the head gasket?
Dont you think that 120 is too small?
Thank again. My name is also Alejandro.
E-mail: [email protected]
Please add Alejandro to the subject.
for the polini kit its known for its greater torque than malossi so i suggest 30mm is cool but its more fuel gulper.but with 30mm you are covered from low mid to top. go for it santacama and enjoy the wheelies on stop ligths
ride safe mate
That sounds good mate. What would be the difference between 28 and 30?
Thaks.
Thanks, but I know the basic functioning of carburetors, what I want to know is how the 28 and 30 will work with my setting to avoid spending money and time unnecessarily. If you use a carburetor too large the engine will not work well, so I want to know the behavior of the engine (Polini kit + Polini exhaust) with 28 and 30.
If you are sticking with the original cylinder, open up the exhaust port about 1mm each side, this will give you a bit more power. Don’t open too much though.
I already have mounted the cylinder kit and the exhaust Polini. What I want to know is what will best carburetor, 28 or 30. The behavior of the Polini kit and the Polini exhaust is very good wiht the original carb, so I think that a larger carburetor will get more power, but which one: 28 or 30.
Thaks.
Hi you should Run a 120 or above Jet and change your 4th gear to a T5 4h gear you also need to gill a small hole under your air filter give me your email and i will send you a pic of one done also what clutch are you running
Alex
Buy a MMW head for Polini, works very well.
No autolube anyway.
What will be better 28 or 30 for city use?
Thaks mate.
You are going to ride this to work, so it needs to be reliable.
Please don’t do all this if this is your first time tuning and you still want it to be reliable enough to get to work.
Forget about the polini. It needs to worked over if you want it to be reliable. Port edges are too sharp and the bore is a little tight. Big carb will drink too much fuel and be alot of hassle to port right and is not really needed unless you plan to have more than 20hp.
Stick with the original cylinder and just get a sito+ exhaust if you want to do it simple. If you want to change the cylinder too just get a pinasco 215. It has got a head, and needs no more porting than what is there already. Pinasco and sito+ will give you about 14-15 hp at the wheel which is quite a lot more than the standard 9 hp@wheel (12hp is at the crank)
In any case you MUST forget getting the polini exhaust. It makes no more power only noise. For a good high revving exhaust (which the polini pretends to be) get a JL or a SIP pipe. Or perhaps a simonini if you want it cheap…
I just order a carburetor type PWK 28/38 from scootrs.com, apparently the largest main jet is 118. Will it be enough? What would be the appropriate jets?
Hi: Now I am thinking about a new carb.
What do yuo think: 28 or 30 mm?
Thanks a lot.