I am not suggesting this way, let us say, I am writing this for fun.
Some people use this way to adjust fuel. I used it for one of my Harleys.
1.Buy O2 sensor bungs and plugs.
2.Weld them to exhaust pipes about 2" (?) from cylinder head.
3.Install narrow band (I used narrow band) O2 sensor, connect heater wires to battery, voltmeter to signal wire.
4.Find 0.45V screw position, then turn it out 1/4 turn.
5.Remove sensor, install plug.
Some people use this way to adjust fuel. I used it for one of my Harleys.
1.Buy O2 sensor bungs and plugs.
2.Weld them to exhaust pipes about 2" (?) from cylinder head.
3.Install narrow band (I used narrow band) O2 sensor, connect heater wires to battery, voltmeter to signal wire.
4.Find 0.45V screw position, then turn it out 1/4 turn.
5.Remove sensor, install plug.

O2 Oxygen Sensor Weld On / Weld In Bung Plug & Nut Cap Kit M18 x 1.5 | eBay
Type: Oxygen Sensor Bung / Curve Notched Adapter. 1xStainless Steel Oxygen Sensor Bung. 1xIron Oxygen sensor plug. if item is defect or wrong when it. Communication always is best way to solve problem.
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