Are Motorbike Carriers Legal in Australia? Plates, Lights and Weight Rules Explained

Short answer: yes, towbar motorbike carriers are legal everywhere in Australia, as long as you follow three rules. Your number plate must stay visible, your lights must not be obscured, and the combined weight of carrier and bike must sit within your towbar's rated download. This guide covers all three, plus the state differences.

Rule 1: Your number plate must stay visible

A towbar carrier with a bike on it will almost always block the rear plate. Driving with an obscured plate attracts fines and demerit points in every state and territory, and a handwritten or homemade copy plate is illegal nationwide.

The fix is an auxiliary plate (sometimes called a bike rack plate or accessory plate). It is a smaller official plate carrying the same characters as your rear plate, ordered from your state roads authority for a modest fee. Fit it to a hard flat surface on the back of the carrier or bike, keep it below 1.3 metres from the ground, and make sure it is lit at night. In WA these are ordered through the Department of Transport auxiliary plates service; every other state has an equivalent through its transport authority.

Rule 2: Your lights and indicators must not be obscured

Australian road rules require your brake lights to be visible from about 200 metres and your indicators from about 30 metres. A dirt bike sitting across the back of a ute or SUV will usually block at least one of them, and that makes the setup illegal even if your plate is sorted.

The answer is a carrier light kit: a rear light bar with tail, brake and indicator functions that mounts behind the bike and plugs into your trailer socket. MotoCarriers makes a light kit with indicators and brake lights sized for our carriers, and it is the difference between a rig that gets defected and one that sails through a roadside check. If you already run a trailer, the wiring is identical, so fitting takes minutes. See it alongside the MotoCarrier 190.

Rule 3: Stay under your towbar's download rating

This is the rule most people miss, and the one that matters most for safety. Every towbar has a rated ball download (static vertical load), stamped on the towbar tongue or listed in your vehicle handbook. The carrier and bike hang entirely on that point.

The maths is simple. Our carrier weighs 25 kg. Add a 105 kg enduro bike and you are asking the towbar to hold 130 kg of download. Most factory towbars on utes and 4WDs are rated between 150 kg and 350 kg download, so a full-size dirt bike is fine on most of them, but a small hatchback with a 75 kg rated bar is not the vehicle for the job. Check your own numbers before you buy any carrier, ours included.

Two related points. First, the carrier's own load rating matters: the MotoCarrier 190 is rated to 180 kg, which covers every MX, enduro and trail bike and most e-motos. Second, weight this far behind the rear axle also counts toward your rear axle load, which is another reason to keep the whole setup as light as possible. An aluminium platform carrier at 25 kg leaves far more of your towbar's rating for the bike than a 40 kg steel one.

Overhang and projection

A motorbike sits across the vehicle rather than pointing backwards, so rear overhang is rarely an issue. Width is the one to watch: if the bars or wheel project past the sides of your vehicle, keep the projection modest and make sure nothing sharp leads the edge. If any load projects more than 1.2 metres behind the vehicle, you need a flag in daylight and a red light at night, though this almost never applies to a sideways-mounted bike.

State by state

The three rules above apply nationally. The paperwork differs slightly: NSW, VIC, QLD, WA, SA and TAS all issue official auxiliary or accessory plates through their transport authorities, and Tasmania publishes a specific guidance bulletin for carriers. Fines for obscured plates and lights vary by state, from roughly $100 to over $500 plus demerits. If in doubt, a five minute call to your state authority settles it.

The compliance checklist

Before you drive: auxiliary plate fitted and visible, light kit plugged in and tested (brake and both indicators), carrier and bike weight added up and checked against the towbar download rating, bike strapped at bars and rear wheel, anti-wobble bracket tightened, straps re-checked after the first 10 to 15 minutes of driving.

FAQs

Are motorbike carriers legal in Australia?

Yes, in every state and territory, provided your number plate remains visible (use an official auxiliary plate), your lights are not obscured (use a light kit), and you stay within your towbar's download rating.

Do I need a light kit on a motorbike carrier?

If the bike or carrier blocks your brake lights or indicators, yes. Brake lights must be visible from around 200 m and indicators from around 30 m, so most setups need a rear light kit with brake and indicator functions.

Do I need a special number plate for a bike carrier?

You need an official auxiliary plate matching your rear plate, ordered from your state transport authority. Homemade or printed copies are illegal in every state.

How much weight can a towbar carrier take?

Whichever is lower of the carrier's rating and your towbar's ball download rating. The MotoCarrier 190 is rated to 180 kg; most ute and 4WD towbars are rated 150 to 350 kg of download. Always check your towbar's stamped rating.

Are towbar motorbike carriers safe at highway speed?

Yes, when the weight is within ratings, the bike is strapped at the bars and rear wheel, and an anti-wobble bracket takes the slop out of the hitch connection. Re-tension straps after the first 15 minutes.

This guide is general information, not legal advice. Rules change; confirm current requirements with your state road authority.

Ready to carry the bike without a trailer? The MotoCarrier 190 is 180 kg rated, 25 kg light, from $349 delivered with free shipping Australia-wide, and the matching light kit keeps the whole setup legal.