Tag Archives: trailer regulations nsw rta motorcycle

Motorcycle Trailer Building Notes, Regulations

So my bike is all happy for touring again, I’ve done ~ 2000km on it in the last month, trundling back and forward to work, and there’ve been no hiccups.  Working through my pack list for the Karuah River Rally in a month’s time, my brain started ticking over how it’d be nice to be able to pack some extras (you know, couple of extra car batteries for power, couple of 10L water cans, etc..), and just to get the normal camping weight off the bike..  And I started thinking about trailers again.  So lets pick it back up as a project, and potter on it 🙂

Note that everything here is geared towards a small trailer TOWED BY A MOTORCYCLE.  If you are looking at building a box trailer to tow behind a CAR, then the dimensions, and thus quite a few considerations (especially IRT lighting) will be VERY different..

Initial Planning

First things first, we need to find out what regs we need to follow, and build a bit of a checklist!

First thing to do, is download Vehicle Standards Bulletin 1.  It’s the federal bible for trailer building!  VSB 1 lives here.

Firstly, we’ll need a Vehicle Plate.

A Vehicle Plate must show at least:

  • Manufacturers Name
  • Trailer model
  • Vehicle Identification Number
  • Date of Manufacture (month/year)
  • Certification Statement – This trailer was manufactured to comply with the Motor Vehicle Standards Act 1989
  • Can include the tyre placard (VSB1:section 16) to save having an extra plate.  Letters to be at least 2.5mm high
  • VIN issued by RTA

Ahhh, the VIN. That was where I came unstuck last time.. – At the time, I was doing contract work in Sydney (and living for the most part), but was officially living (and had my business registered) in the ACT.    VIN Numbers are theoretically managed by Standards Australia.  But in reality they just hand out chunks to each state Registering Authority.  Where it’s tricky for someone who lives/works across two states, is that the trailers VIN must be issued by the state Registering Authority in the state where 80% or more of the supplies were *delivered*. This is irrespective of what state you are actually going to do the initial registration in.  So in the case that I spent more time in NSW, and wanted the supplies delivered there, and I’d build the trailer at nights while in Sydney, after enquiring with the ACT, I was informed that I would have to contact the NSW RTA to secure a VIN number to provide to ACT Urban Services.

Ok, so I contacted the RTA.  No, they only issue VIN numbers where THEY are the actual Registering Authority.  They suggested I contact Standards Australia, as the ultimately responsible VIN issuer.  Standards Australia came back to me saying that no, they only maintain the STANDARD, and do not have ANYTHING to do with actually issuing the numbers, and please talk to ACT Urban Services to get a number, as they are legally required to issue a number at the time of registration.

At that point I replied to the lady from Standards Australia, Cc’d in the fellows from ACT US, and NSW RTA, with a ‘Hi all, I am EXTREMELY confused here..  My trailer will be built at nights in Sydney, registered in the ACT, as that is my official address.. HOW do I get a VIN number??  ACT says talk to RTA, as ACT only issues VIN’s where the trailer is 80% built in ACT, as proven by delivery addresses on receipts.  RTA says they ONLY issue VIN’s when they are the registering authority, but as I live in the ACT, I *CANNOT* register the trailer in NSW, so talk to Standards Australia to get a ‘federally issued’ VIN.  SA say that they only maintain the standard, but the standard says that ACT must issue the VIN.     Pleeease figure this out!! 🙂 Thankyou.’   I received a reply from the fellow at ACT Urban Services, saying he’d push it up his chain of command and get something sorted out..  That was two and a half years ago now, and I haven’t yet heard back.

However I have since sorted out the clusterf*** that was transferring my license from the ACT to NSW (ACT never cancelled my NSW license when I shifted to the ACT back in the dark ages!), and I’m ‘officially’ an NSW resident, so I’ll just be registering an NSW-built trailer in NSW.

Ok, back to the checklist, where were we?

Oh, Vehicle Plate.  I’m sure I read somewhere that the RTA supply the plate.. But I can’t find that ANYWHERE.  You can buy plates from trailer supply places, so add that to my purchase-list..  But ask the RTA..

Now we keep reading through VSB1..

Registration plate.  Provision must be made for mounting of a 372x136mm registration plate to the rear of the trailer.  no part of the plate to be more than 1300mm above the ground. (This is a motorcycle trailer, that’s not a problem, lol!)

Rego Label holder.  Must be on the left hand side of the trailer.  See ADR61/02:9.2 for more information.  Ok we’ll look that up later..

Some terms we need to define..

Trailer Type.  Well that’s easy, we’re building a Box Trailer

Trailer Category.  Under 750kg, Very Light Trailer (TA).  That’s us!

Aggregate Trailer Mass (ATM).  The total mass of the trailer including the maximum load as defined by the manufacturer (aka me!).  Includes the mass imposed on the towing vehicle.  (AKA you can’t subtract the 30kg or whatever that it puts on the towball..)

Gross Trailer Mass (GTM).  The mass imposed on the ground by the tyres of the trailer.  So that’d be the ATM less the ball weight?  Hehe, ball weight, lol.

Tare Mass. The total mass of the trailer when not carrying any load, but when ready for service with all standard equipment and options fitted.  So including things like tent pole holders, or antenna mast mountings, etc.  Includes the ball weight.  So essentially GTM but unloaded..

Length. That’s towbar to rear of trailer.

Width.  Point from the side extremities, including lamps etc.


First thing to note, is that all lights must meet ADR requirements.  This is either by being listed on the RVCS, or being stamped with ECE compliance.  That means no cheap-arsed ebay knockoffs.. 🙂

Rear position Lamps (tail lamps), 2 lamps.   Must operated with towing vehicle tail lamps.

Rear stop lamps (Brake lights), 2 lamps.  Must operate with towing vehicle stop lamps

Direction Indicator Lamps (Turn Signals), 2 lamps.. Must operate with towing vehicle indicator lamps.

Rear registration lamp, at least 1 (Some lamps may only be approved if fitted in pairs).  Must operate with towing vehicle tail lamps.

Side marking lamps, arrangement at the side, one lamp each side within the first third and/or one within the last third. (aka in the first or last third of the length.  Since the drawbar will be long on a bike trailer, I’d have it within the last third).  Note, that these are ONLY required on trailers more than 6 meters long.  However as anyone who has towed at night knows, side marker lamps are the only way to know where your trailer is!  So I ALWAYS have them on a trailer…  There is no specific requirement for how these are electrically connected.  I’ll have them on with the tail lights..


Front – non triangular, 2 required at the outer edges of the front, 150mm maximum in from the edges, at least 600mm apart, at least 250mm from the ground, and 900m maximum from the ground

Rear – triangular OR non-triangular, 2 required at the outer edges of the rear.  If triangular, must point up.  If non-triangular, may be grouped as part of the rear lights. (so reflector in the light group? ok, that’s easy..)  400mm maximum in from the edges, at least 600mm apart, at least 250mm from the ground, 900mm maximum from the ground

Side – non–triangular, At least one on each side, within the middle third of the trailer, minimum 250mm from the ground, maximum 900mm from the ground.

Interesting, there is no specific mention of colours!  Although earlier there was mention of the trailer NOT showing white to the rear, or red to the front..  So that would suggest white to the front, and red to the rear.. and yellow being the only safe colour to the side 🙂

Electrical Wiring

  • Must be supported at intervals of no more then 600mm apart.
  • Be insulated at joints
  • be located so that it does not become overheated, or contact moving parts
  • be protected from chafing
  • have an earth return between the trailer and the towing vehicle.  OMG, are they kidding? someone would consider the hitch-to-ball coupling a suitable connection for the earth? lol!

Draw bar, chains, couplings

Drawbar to be securely attached to a ‘substantial portion’ of the trailer.  Longitudinal tension and compression (Newtons) 1.5 x 9.81 x ATM (kg).  That would suggest to me that it needs to be able to withstand the towing vehicle accelerating at 1.5 gravities.  Having owned a ZZR1100, and knowing that it was only JUST able to reach 1G of acceleration, I know that that’s quite a bit of force 🙂

Transverse thrust, and vertical tension/compression is (N) 0.5 x 9.81 x ATM (kg).  Tranverse thrust, what’s that?  Vertical tension/compression? that’d be up and down on the towbar as you go over bumps?

Well, basically what those two are saying, is the drawbar needs to be REALLY WELL ATTACHED.. 🙂  I’ll likely have mine very securely welded below the floor frame and front and back (and any other cross-braces I put in the floor..)

Chains.. Well, under 2.5 tonne ATM, must have one safety chain complying with AS 4177.4-1994 or AS 4177.4-2004-Part4  The attachment point for the chain should not come into contact with the road when the trailer is disconnected.   ‘Safety chains, which ave the mechanical T grade property, are not suitable for welding’.  Do we HAVE to weld? Or is a shackle between trailer and chain ok?  Find out!

Coupling – Must have  quick release coupling which is designed to be used without tools.  It must be positive locking with provision for a second independant type.  Coupling to be mounted so that the height of the center of the body of the coupling is 350-420mm above the ground when loaded.   Hmm, check the height of my motorcycle’s tow-ball!.  Coupling to be marked in accordance with ADR62/01 and ADR62/02.  This is:

  • The manufacturers name or trademark.
  • The mark ‘50’ (50mm ball)
  • Maximum rating for the coupling (750kg)
  • a code to indicated serial, batch, production date, or similar
  • ‘DO NOT WELD’, if made from non-weldable material
  • ‘WELD ONLY’ if the coupling is to be attached by welding only.

Mud Guards

Must be designed to protect other road users from thrown up stones, ice, snow, water, mud, etc, and prevent people contacting the moving wheels.

Wheel guards must provide continuous protection between a point in area ‘A’ and a point in area ‘B’, and must cover the overall width of all tyres.  May include mudflaps, and need not be less than 230mm from the ground.

Axles and suspension

Wow, there is no information given for this, for a single-axel trailer which is not going to have galvanised springs. Booyah!  I think..

Wheels and Tyres

All wheels and tyres must comply with ADR’s 23 or 42.  Must haev a tyre placard in a prominent position, can be part of the vehicle plate.  Must show:

  • Manufacturers recommended tyre size
  • Tyre load rating
  • Speed rating
  • Cold inflation pressures
  • ‘The tyres fitted to this vehicle shall have a speed category not less than ‘L’ (120km/h)’    (There is another option, but i wouldn’t want less than 120k/h on a bike trailer!)


Rear Overhang – Must not exceed the front load space.  There is no definition of ‘front load space’, but one can assume that it is the ‘load space’ portion in front of the axle. As compared to the portion behind the axle, which is the ‘rear overhang’…  So what this is saying is that there must be more of the ‘box’ on the box trailer, to the rear of the wheels, than at the front of the wheels..

Ground Clearance – Within 1 meter on front and back of the wheels, must not be less than 100mm ground clearance, excepting the wheels, tyres, and wheel hubs.

And that’s all she wrote, as far as regulations relating to *getting the trailer registered* go.  The only other caveat is that the trailer must be build ‘fit for purpose’.  I.e. don’t use weak materials and ‘hope it will do’..

NSW RTA Towing Regulations.

Refer NSW RTA ‘Towing Trailers’ booklet.

Maximum Towing Mass (Loaded trailer weight).  Must not be more than the unladen mass of the towing vehicle.  In my case, this is 243kg.  That’s PRETTY. DARNED. HEAVY.   Of course, if the vehicle manufacturer has specified the towing mass, then that would be the maximum (up to the 750kg trailer limit). But most motorcycle manufacturers (even BMW!) don’t actually specify a maximum towing mass…


  • Vehicle Plate
  • 2 x rectangle white reflectors
  • 2 x rectangle yellow reflectors
  • 2x rear light groups (yellow indicator, red reflector, red stop/tail combo)
  • 1 coupling (swivel type, since it’s to tow behind a motorcycle!)

Ask the RTA

  • Do they supply the Vehicle plate?
  • At what point to I get a VIN? Does the RTA put that on the build plate for me after inspecting?  Do they even inspect, or is that only the inspection mob?
  • Does chain have to be welded? Or is bolted fine?

Other things to find out

  • Talk to eco-tec auto gas (My preferred vehicle inspection place – They’re VERY easy to deal with!) and find out if they can do a blue-slip on a home-built trailer..  RTA site says they just need to be a full AUVIS station, which they are..
  • What is chain with a ‘T’ grade property?