A one-way road has no sign prohibiting right-side parking. What is the key limit if parking on the right-hand side is otherwise lawful?

1. The outer edges of the right-side wheels may not be more than 450 mm into the roadway
2. The motorcycle must face oncoming traffic
3. The rider must leave the headlamp on for 24 hours
4. The motorcycle must be parked exactly in the centre of the lane