#Mercury 125 2 stroke tuning how to#

The jet needle is connected to the throttle valve and controls the mixture from approximately Вј вЂ“ Вѕ throttle. Replacing the existing slow jet with a higher-numbered jet will make the mixture richer, while a lower-numbered jet will make the mixture leaner. The slow jet is interchangeable with jets that will provide a leaner or richer air-fuel mixture. Turning the pilot air screw in will richen the air/fuel mixture while turning the screw out will lean out the mix. The atomized air/fuel mixture then passes into the throat of the carburetor. The slow jet draws fuel from the bowl and mixes it with air from the pilot air jet passage. This system controls the air-fuel ratio from closed throttle to Вј throttle. The slow jet works with the pilot air screw. They come in many shapes, but their function is the same.Дў-Stroke Carburetor Jetting Structure Slow Jet 2-Stroke Carb Adjustment вЂ“ Slow Jet You will almost always find a slide style throttle valve on 2-stroke carburetors. Throttle Valve вЂ“ The throttle valve is directly connected to the throttle cable and regulates the flow of air through the carburetor.Getting that idle just right can be tricky sometimes. This is where you will spend a lot of time during 2-stroke carb tuning. Pilot Air Screw вЂ“ Controls idle speed by regulating the amount of air passing through the pilot jet passage.Float Valve вЂ“ The float valve regulates the flow of fuel from the fuel tank to the carburetor bowl.No 2-stroke carb adjustments will work if the bowl is always flooding. The floats are made of hollow plastic or metal connected to the carburetor body by a hinge. Float Assembly вЂ“ The float assembly sits inside the bowl to regulate the fuel level in the carburetor bowl.The bowl also houses the float assembly.Дў-Stroke Carb Body And Bowl Internal Carburetor Components Bowl вЂ“ The carburetor bowl is located on the bottom of the carb and holds the fuel to be sent through the jets.Body вЂ“ The carburetor body houses all the moving parts and jets, and mixes the air and fuel on its way to the cylinder.Parts of the Carburetor and What They Do Carburetor Body

#Mercury 125 2 stroke tuning how to#

Knowing how to change your jets and needles is one thing, but it wonвЂ™t do you any good if you donвЂ™t understand how the changes will affect your dirt bike. Although some may have different configurations or features, they all do the same thing вЂ“ mix fuel and air. Once you understand the basic functionality of one 2-stroke carburetor, you can apply that understanding to ANY carburetor.ДЄlmost all 2-stroke carbs operate the same way. This 2-stroke carb tuning guide will give you all the information you need to tune your 2-stroke carburetor for peak performance, no matter the make or model. Tuning Your 2-Stroke Carburetor For Peak Performance.Why Proper Carb Tuning Is Critical For 2-Stroke Engines.Parts of the Carburetor and What They Do.