Typically found in a motorcycle’s intake and exhaust system., an O2, or oxygen, sensor is a data gathering component used on many fuel-injected motorcycles.
An oxygen sensor sends measurements of the amount of oxygen flowing into the intake or exhaust system to the electronic control unit. The ECU then adjusts the fuel-to-air ratio for performance or emissions-related purposes.
Most fuel-injected motorcycles run on a predetermined fuel setting with small adjustments made as oxygen levels change. At higher elevations, for example, the ECU would adjust the fuel delivery against lower oxygen levels.
Replacing the stock exhaust system with an aftermarket upgrade may cause problems if a mounting point for the O2 sensor is not present. An O2 sensor eliminator kit is recommended to prevent incorrect O2 sensor readings.
Tuning the fuel-injection system is possible with a stock O2 sensor through the use of an aftermarket fuel-injection controller, allowing the user to set the fuel curve as desired.
The capability to produce an ever-adapting fuel injection map is possible through the use of a properly equipped fuel-injection controller and O2 sensor. Designed primarily for closed-course racing, this type of system could produce a strong power curve against changing conditions.