YESON System EFI Motorcycle Oxygen Sensor 27H-03 Universal Type Factory Direct

This EFI motorcycle oxygen sensor is designed for bikes equipped with YESON EFI systems, fits 125cc-250cc motorcycles from brands such as Chunfeng, Lifan, and Zongshen produced after 2015. This sensor monitors exhaust oxygen content in real time and feeds the ECU to adjust the air-fuel ratio, ensuring combustion efficiency and emission compliance. OEM number YESON; compatible models 7H-03, 27H03, 27H-03L, 27H03L for cross-checking stock. Replacement difficulty: medium; remove front exhaust pipe section; use a dedicated socket and apply anti-seize compound. Factory-direct supply; volume pricing available; suitable for repair shops or parts distributors.