Unless a road sign says otherwise, the general speed limits are:
- 60 km/h on a public road in an urban area.
- 100 km/h on a public road outside an urban area (not a freeway).
- 120 km/h on a freeway.
A road sign always takes precedence over the general limit. If a freeway is signed at 100 km/h, that is the limit.
Some vehicles have their own maximum regardless of the road:
- 80 km/h for a goods vehicle with a GVM of more than 9 000 kg.
- 100 km/h for a bus or minibus (taxi) carrying passengers with a GVM of more than 3 500 kg.
The lower of the two limits always applies: a heavy truck in a 60 zone is limited to 60, and the same truck on a freeway is limited to 80.
The speed limit is a maximum, not a target. You must drive at a speed that lets you stop within the distance you can see to be clear, so slow down in rain, fog, dust, heavy traffic or on loose surfaces. There is no allowance for exceeding the limit while overtaking; if you cannot complete an overtaking manoeuvre within the limit, do not start it.
Source: iDriving manual p.91