Why is EFI better than a carburetor?
Choosing a carburetor and tuning it is always a series of compromises. A carburetor is a demand device dependent upon the velocity of the air entering the venturi to create the air/fuel mixture that feeds the engine. A carburetor maintains a series of fuel circuits to help maintain the best possible fuel mixture. The idle circuit, intermediate and main jetting circuits are used to tune the mixture across the operating RPM range of the engine. These different fuel circuits can interact with each other creating rich and lean spots in the fuel curve. Some riders will go as far as to add one or more additional fuel circuits (Thunderjet) in an effort to improve the fuel curve. The interactions of these additional circuits further complicate the tuning efforts. A change in jetting to one fuel circuit can impact the required jetting in another circuit. Sound complicated? It certainly can be. Lets simplify matters and assume a carburetor with nothing more than an idle circuit and main circuit.
