Where can I weld a lambda sensor bung on the exhaust system?
The placement of the O2 sensor is not very critical. It is a heated sensor and its temperature is controlled by the AFR Tuner, so it will adapt to the placement between wide limits. If the sensor is anywhere on the collector pipe near the footpeg then it will be fine. Motorcycle exhausts are too short for overcooling to be a problem and overheating is unlikely to be an issue on naturally aspirated engines.
