A device engineered to replace the oxygen sensor in specific Husqvarna motorcycle models. It simulates the signal normally sent by the oxygen sensor to the engine control unit (ECU). This allows the ECU to operate under a pre-programmed fuel map, often bypassing closed-loop fuel control.
These devices are often employed when modifications are made to the exhaust system, such as installing aftermarket pipes, or when seeking to optimize engine performance. They can be beneficial in addressing issues stemming from oxygen sensor malfunctions, providing a cost-effective alternative to sensor replacement and, in some cases, improving throttle response and overall rideability. Historically, such devices arose from the need to circumvent limitations imposed by stock emission control systems, especially in off-road or racing applications where absolute power takes precedence over emissions compliance.