This is a top to bottom explanation, slide, needle, fuel feed tube, main jet, bowl. At the bottom of the fuel feed tube is the main jet. The needle moves in and out of the fuel feed tube which is where the fuel is fed up from the bowl into the carburetor. When the throttle is twisted, it opens up the slide, allowing more air and fuel to be drawn into the engine, producing power and increased revs.Īttached to the base of the slide is the needle.

The slide is controlled by the throttle cable. The slide controls how much air can be drawn through the carb. The Engine draws air through the carb, the carbs internal shape creates a venturi effect drawing fuel in with it. Below I’ll be going through a very simplified explanation of the functions of each part of the carb, and some basic examples of tuning it.Īll carburetors work off a few basic principles, fortunately for scooter tuners, scooter carbs are some of the most mechanically simple around. The next obvious step before doing anything else, is to familiarize yourself with the components of the carb, and what they do. Certainly an easy way to save yourself alot of extra hassle, as many scooters have different fitment methods. For many models Malossi make a specific kit with included fitment parts to fit specific bikes, which is really handy particularly when it comes to chokes, inlet & outlet size, and mounting type. If you’ve gotten yourself a performance carb, the first thing to do is make sure that fits the scooter. These principles can also be applied to standard carburetors. In this article were going to be going through the basic components of carb tuning, in particular the PHBG ( a benchmark carb in performance scootering). Where do you start, what does what, and how do you make sure it doesnt blow up?! If that's not for you, then we've loads of other cool scooter parts too! Supplied with a 65 main jet and 50 pilot it's readily set up for 50cc engines with a fully de restricted exhaust system however if you have a different setup the main jet size will need.Performance carb tuning can be one of the most daunting tasks of tuning a scooter. Get tuned with our Dellorto PHVA 17.5mm carburettor for Piaggio 50cc engines here. How To Quickly Determine The (Dell’Orto) Carburetor Main Jet Size 106151 views / Posted SeptemHow To Check Your Spark Plug for the Correct Carburetor Setting. Find your replacement battery to power up your scooter, razor or electric bike. Electric Bike and Scooter Batteries from Batteries Plus Bulbs. 2.25 & 2.50 nominal section widths are rated for 75 mph. Raise the Main Jet size ONE It should be about the color of a pancake or waffle.

Drop the Main Jet size ONE Is it white? Then it's lean. These are answers to questions we get asked over and over. Tuning tips for bike engines, monkey bikes and pit bikes.

Piaggio zip 50 main jet size calculator