The knock sensor is attached to the top of the cylinder block in the areas between the 2nd and 3rd cylinders.
You will need a TORX E12 key.
1. Place the vehicle on a pit or lift.
2. Disconnect the wire from the terminal «minus» battery.
3. Remove the crankcase protection (see «Removal and installation of mudguards and engine crankcase protection»).
4. Press the spring retainer of the knock sensor wiring harness block and disconnect the block from the sensor.
5. Loosen the bolt securing the sensor to the engine block...
6.... and, having unscrewed the bolt by hand, remove the knock sensor.
7. Install the knock sensor in reverse order. Tighten the sensor mounting bolt to 20 Nm.