MXT SPORT Carburetor 19mm compatible with Honda Mini Bike Dax CT70 ST70 CT90 ST90 with Fuel Tap

The MXT-SPORT carburetor with a 19mm bore is intended for Honda Mini Bikes as well as similar Pit, Dirt, and Trail Bikes. As a central component of the mixture formation, it controls the metering of the fuel-air mixture depending on engine speed and throttle position. The design is coordinated for easy integration into existing intake systems.

Product Features:

• Carburetor with 19mm bore
• Flange connection for the intake manifold
• Integrated fuel tap in the float chamber
• Main and pilot jets pre-installed at the factory
• Designed for Honda Mini Bike and comparable vehicle types

The flange mounting and defined bolt hole spacing are crucial for mechanical fit on the intake manifold, ensuring the carburetor sits without stress and does not draw in air leaks. The integrated fuel tap combines fuel shut-off and reserve function directly on the carburetor, simplifying integration into setups with limited installation space. For stable engine operation, the basic tuning via main and pilot jets remains decisive, especially if the engine or intake side deviates from the standard condition.

Technical Details:

• Bore: 19 mm
• Bolt Hole Spacing Flange Intake Manifold: 48 mm
• Connection Width Air Filter Side: 33 mm
• Main Jet: No. 60
• Pilot Jet: No. 35
• Fuel Tap: integrated in the float chamber with function Off-Reserve-On

The bolt hole spacing of 48 mm determines whether the carburetor can be mounted without modifications to the intake manifold, while the connection width of 33 mm on the air filter side is relevant for compatibility with the air filter and therefore for the air flow. The jetting of No. 60 and No. 35 forms a basis for the basic tuning in the standard condition, but may require adjustment if the air filter or other engine variants are changed. The Off-Reserve-On function on the fuel tap supports controlled fuel supply and is functionally important to avoid malfunctions due to incorrect position.

Vehicle and Model Compatibility:

• Honda Mini Bike
• Pit Bike
• Dirt Bike
• Trail Bike
• Honda Dax models such as CT70, ST70, CT90, ST90

Note: Compatibility requires standard intake and mounting dimensions of these vehicle types.

Mounting and Application Instructions:

• Before mounting, bolt hole spacing and connection widths must be checked. The carburetor must be mounted without stress on the intake manifold. The fuel line is correctly connected to the integrated fuel tap. After installation, idle speed and throttle response must be checked. Careful mounting supports uniform mixture formation and stable engine operation.

Stress-free mounting and tight connections are functionally relevant because air leaks distort the mixture formation and impair idle speed and throttle response. If the fuel tap is correctly connected and operated in the correct position, the fuel supply remains stable, which makes the tuning more understandable. The final check of idle speed and throttle response shows whether the existing jetting is suitable for the respective setup or whether re-jetting is required.

Note regarding inspection before purchase:

• Before purchasing, the specified connection dimensions and the installed jetting must be compared with the existing vehicle setup. Deviations due to previous modifications may require an adjustment of the jetting.

Brief info: Carburetor - Installation, Setting & Tuning

Installation: Mount carburetor without stress, check intake manifold and gaskets for air leaks, adjust throttle cable smoothly, ensure fuel supply (gasoline, oil & vacuum).

Basic Setting: Mixture screw usually 1.5 - 2.5 turns open, adjust idle screw for stable idle speed, always tune engine when warm.

Tuning:

• Main jet = full throttle / high load
• Needle position = partial load & acceleration
• Pilot jet = idle speed & starting (usually does not need to be changed)

Check: Inspect spark plug image

• white = too lean
• black = too rich
• brown = optimal

Important: New carburetor tuning is absolutely necessary after changes to air filter, exhaust or cylinder.

About the Manufacturer MXT

MXT is the powerful in-house brand of Heavy Tuned and stands for high-quality replacement and tuning parts for motorcycles, scooters and mopeds.

As a reliable alternative to OEM parts, MXT offers a wide range of cylinder kits, carburetors and crankshafts to variator components, fairing parts and batteries. The products convince by solid workmanship, precise quality and a strong price-performance ratio.

Ideal for riders looking for durable spare parts and tuning parts for many vehicle models.