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Rules of the road · about 2 min read

General and vehicle-specific speed limits

Understand the rule, its conditions and how to apply it

What you will learn

  • Explain the purpose of this rule.
  • Apply the procedure and recognise its limitations.

Purpose and essential terms

A speed limit sets the maximum permitted speed, not the speed you must aim for. General limits apply even without a sign: the reference manual gives 60 km/h in urban areas, 100 km/h outside urban areas on roads other than freeways, and 120 km/h on freeways, unless a sign indicates otherwise.

Some vehicle classes have lower limits. You must know both the road’s limit and the limit applying to the actual vehicle or combination. Weather, grip and visibility can require a speed below every legal maximum.

Key idea: A speed limit sets the maximum permitted speed, not the speed you must aim for.

How to apply the rule

Identify the road type and any posted restriction. Check the vehicle’s class, gross vehicle mass and combination details. GVM is the manufacturer’s specified maximum mass of the vehicle and load, not merely the load aboard today; GCM refers to a combination’s specified maximum mass.

The reference states 100 km/h for buses and minibuses and 80 km/h for the specified goods vehicles above 9,000 kg GVM, qualifying goods-vehicle/trailer combinations and articulated vehicles above the listed mass. A breakdown vehicle towing another vehicle is also in the 80 km/h list. Obey a lower applicable posted restriction.

Key idea: Identify that its GVM places it in the reference 80 km/h vehicle-class restriction.

Conditions and easily confused points

A 120 km/h freeway sign does not cancel a lower vehicle-specific limit. An empty qualifying heavy goods vehicle does not automatically escape a rule defined using its specified GVM.

The 30 km/h rope-or-chain towing restriction is a separate rule and can be lower still. Work through every applicable restriction rather than choosing the largest number seen on a sign.

Key idea: Apply the full rule to the actual vehicle, road and conditions.

Worked road situation

A goods vehicle has a GVM of 10,000 kg and travels on a freeway posted at 120 km/h.

  1. Identify that its GVM places it in the reference 80 km/h vehicle-class restriction.
  2. Do not use the 120 sign to override that lower limit.
  3. Reduce further if conditions make 80 km/h unsafe.

Quick recap

  • Identify that its GVM places it in the reference 80 km/h vehicle-class restriction.
  • Do not use the 120 sign to override that lower limit.
  • Reduce further if conditions make 80 km/h unsafe.

Practice questions on general and vehicle-specific speed limits

1 Does a 120 km/h sign cancel a lower limit applying to your vehicle class?

  1. No, the lower applicable limit still applies
  2. Only at night
  3. Yes, every vehicle may do 120
Show the answer

Answer A: No, the lower applicable limit still applies

General limits are 60 km/h in urban areas, 100 outside urban areas except freeways, and 120 on freeways unless a sign indicates otherwise. The manual sets 100 km/h for buses and minibuses, and 80 km/h for specified goods vehicles or combinations over 9,000 kg and breakdown vehicles towing another vehicle. A higher posted limit does not cancel a lower vehicle-specific limit.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

2 What limit does the manual state for a goods vehicle with GVM over 9,000 kg?

  1. 120 km/h
  2. 80 km/h
  3. 140 km/h
Show the answer

Answer B: 80 km/h

General limits are 60 km/h in urban areas, 100 outside urban areas except freeways, and 120 on freeways unless a sign indicates otherwise. The manual sets 100 km/h for buses and minibuses, and 80 km/h for specified goods vehicles or combinations over 9,000 kg and breakdown vehicles towing another vehicle. A higher posted limit does not cancel a lower vehicle-specific limit.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

3 What limit does the manual state for a bus or minibus?

  1. 100 km/h
  2. 130 km/h
  3. 150 km/h
Show the answer

Answer A: 100 km/h

General limits are 60 km/h in urban areas, 100 outside urban areas except freeways, and 120 on freeways unless a sign indicates otherwise. The manual sets 100 km/h for buses and minibuses, and 80 km/h for specified goods vehicles or combinations over 9,000 kg and breakdown vehicles towing another vehicle. A higher posted limit does not cancel a lower vehicle-specific limit.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

4 Must a general speed limit always be displayed on a sign to apply?

  1. Only in towns
  2. No
  3. Yes
Show the answer

Answer B: No

General limits are 60 km/h in urban areas, 100 outside urban areas except freeways, and 120 on freeways unless a sign indicates otherwise. The manual sets 100 km/h for buses and minibuses, and 80 km/h for specified goods vehicles or combinations over 9,000 kg and breakdown vehicles towing another vehicle. A higher posted limit does not cancel a lower vehicle-specific limit.

Memory tip: Read the full rule, including its conditions and exceptions.

All vehicle codes

Part of the guide: Speed limits and following distance

More rules of the road chapters

Sources: NaTIS Rules of the Road, PDF p. 28, sections 6.27–6.29; iDriving K53 manual, PDF pp. 91–102 (comparison; incomplete text extraction checked against official reference).

AceK53 is an independent study aid based on public road traffic manuals and is not an official test. Always confirm requirements with your driving licence testing centre.