Tuning a TMX 38 requires a systematic approach, as the carburetor is highly sensitive to fine adjustments and fuel contamination.
In an age of closed-loop EFI systems, where a laptop and a wideband O2 sensor do the thinking, the TMX 38 manual feels almost archaic. It demands that you get your hands stained, that you learn the acoustic signature of detonation versus pre-ignition, that you carry a Ziploc bag of spare jets to the track. And yet, for those who submit to its teachings, the reward is incomparable: the crackling, instantaneous throttle response of a perfectly jetted two-stroke, the feeling that the carburetor is not a bottleneck but an amplifier of intent.
The air screw is on the engine side of the carb body. Mikuni Tmx 38 Carburetor Manual
Symptom: Fuel drips out the overflow hoses while parked or running. Causes:
The Mikuni TMX 38 is a performance-focused, radial flat-slide carburetor designed specifically for . By utilizing a flat-slide design in a smooth-bore venturi, it provides significantly improved throttle response and a wider powerband compared to standard round-slide models. Technical Specifications Tuning a TMX 38 requires a systematic approach,
A lean main jet seizes engines; a rich main jet loses top-end power.
The TMX has tiny internal passages. Use pressurized carb cleaner and compressed air; never poke wires through the brass jets. And yet, for those who submit to its
Many Yamaha YZ250 owners swap to the TMX 38 but use the (part #16010-KZ3-J41). This changes the emulsion characteristics slightly, reducing the dreaded "midrange stutter."