O2 Port Bung Adapter - 18 mm to 12 mm

The Bassani O2 Port Bung Adapters reduce an 18 mm O2 sensor port to 12 mm, so Bassani pipes fit newer-model sensor threads.

Sensor thread sizes changed across model years, which can leave a Bassani pipe and a bike's O2 sensor mismatched. These threaded outer and inner adapters bridge that gap, reducing an 18 mm port to 12 mm so the exhaust can run on select newer-model motorcycles. Sold in pairs.

⚠️ VERIFY your sensor thread size and model year before ordering to confirm you need the 18 mm to 12 mm reduction.