Engineering Data

Technical Specifications

Precision engineered in Australia from Australian steel. Every iSi carrier is manufactured to a verified strength to weight ratio. Lightweight enough to handle daily, strong enough for corrugations, carbon frames and full off road loads.

Two Bicycle Carrier manufactured in Australia

Two Bicycle Carrier

Lightweight 2 bike platform

Unit Weight 14.15kg
Rated Load 64kg
Bicycle capacity
1 to 2 bicycles
Per bicycle
32 kg
Per wheel
16 kg
Modularity
Drawbar and Vehicle mount compatible
Max wheelbase
Up to 1600 mm
Max tyre width
Up to 5.1 in
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Four Bicycle Carrier manufactured in Australia

Four Bicycle Carrier

High capacity 4 bike platform

Unit Weight 25.75kg
Rated Load 84kg
Bicycle capacity
1 to 4 bicycles
Per bicycle
32 kg
Per wheel
16 kg
Modularity
Drawbar and Vehicle mount compatible
Max wheelbase
Up to 1600 mm
Max tyre width
Up to 5.1 in
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Drawbar Mount System manufactured in Australia

Drawbar Mount System

Caravan and camper drawbar interface

Unit Weight 9.80 to 21.20kg
Bicycle capacity
n/a
Per bicycle
n/a
Per wheel
n/a
Modularity
Compatible with 2 and 4 Bicycle Carriers
Pivot function
Pivot up and over
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Vehicle Mount System manufactured in Australia

Vehicle Mount System

Ultralight vehicle interface

Unit Weight 4.80 to 6.30kg
Bicycle capacity
n/a
Per bicycle
n/a
Per wheel
n/a
Modularity
Compatible with 2 and 4 Bicycle Carriers
Pivot function
Pivot down to ground
View product

Engineering Philosophy

Why we manufacture in steel

The obvious question: if lightweight matters, why not aluminium? Because lightweight isn't a material property. It's an engineering outcome. Here is why iSi carriers are manufactured from Australian steel, and how we achieve aluminium class weight without aluminium's compromises.

Fatigue life under corrugation

Steel has a true fatigue limit. Below a defined stress threshold, steel can withstand effectively unlimited load cycles without crack propagation. Aluminium does not share this property. Every cycle counts toward eventual failure. On a corrugated outback track, where a bike rack can see millions of high frequency load reversals in a single trip, this difference is the difference between a rack that lasts a lifetime and one that does not.

Repairable in the field

Steel is weldable with standard equipment available in almost any rural Australian town. If the worst happens, your rack can be repaired and put back into service the same day. Cast or extruded aluminium components typically cannot be repaired without specialist equipment and heat treatment, meaning a damaged part becomes a replaced part.

Strength through engineering, not mass

Our stadium style geometry places material only where the load path demands it. The result is a carrier that rivals aluminium competitors on weight while retaining steel's impact resistance, torsional stiffness and long term durability. Lightweight is achieved through design, not by trading away structural margin.

Fully recyclable, made locally

Steel is the most recycled material on earth and our supply chain is entirely Australian. Every iSi carrier is manufactured in Mitcham, Victoria using Australian mild and stainless steel, supporting local manufacturing and minimising embodied transport emissions.

Materials and finish

Primary structure
Australian mild steel and stainless steel
Finish
Sandblasted, zinc primed and textured black Dulux powder coat
Corrosion testing
Salt spray tested
Fasteners
Stainless steel, optional titanium upgrade
Country of origin
Manufactured in Mitcham, Victoria, Australia

Lifetime Warranty

Every iSi carrier is backed by a lifetime warranty against manufacturing defects. We manufacture them once, properly, in Australia, and we stand behind them for the life of the product.

Warranty details

Buyback Program

Upgrading your vehicle or caravan? iSi will buy back your carrier so you can move into a new configuration without waste. Our products are designed to outlast the adventures they are fitted to.

Buyback policy

Weight and specification FAQ

How much does the iSi Two Bicycle Carrier weigh?

The iSi Two Bicycle Carrier weighs 14.15 kg and carries up to 64 kg total load, with a maximum of 32 kg per bicycle and 16 kg per wheel.

How much does the iSi Four Bicycle Carrier weigh?

The iSi Four Bicycle Carrier weighs 25.75 kg and carries up to 84 kg total load, with a maximum of 32 kg per bicycle and 16 kg per wheel.

How much does a complete iSi drawbar mounted bike rack weigh?

A complete two bike rack mounted on a drawbar typically weighs 28 to 29 kg, and a complete four bike rack mounted on a drawbar typically weighs 38 to 39 kg. These figures include both the bicycle carrier and the drawbar mount system.

How does an iSi drawbar bike rack affect tow ball weight?

Because of our unique stadium style carrier design, the centre of mass extends further back from the tow ball than a conventional rack. As a result, approximately 70% of the total mass (including the weight of the bicycles) transfers to the tow ball, and the remaining 30% translates to axle weight. This rearward weight distribution is a key engineering feature of the iSi system and is what allows us to achieve the lightest possible tow ball delta with bikes on board, protecting valuable tow ball capacity for water, gas and gear.

What size bicycles will fit on an iSi carrier?

iSi carriers accommodate a wide range of bicycles including road, gravel, mountain, fat bike and e-bike configurations. Refer to the wheelbase and tyre width figures on each product card for exact fitment limits.

What drawbars does the iSi Drawbar Mount System fit?

The Drawbar Mount System is engineered to mount to a wide range of caravan and camper trailer drawbar profiles. Please contact us with images of your drawbar and we will confirm a solution to suit.

What is the lightest iSi Carrier component?

The Vehicle Mount System is the lightest component in the iSi range at 4.80 to 6.30 kg, depending on the specific vehicle interface.

Are iSi bicycle carriers rated for off road use?

Yes. Every iSi carrier is rated for both on road and off road use, and is manufactured in Australia from Australian steel with a lifetime warranty.

Are iSi carriers safe for carbon frame bicycles?

Yes. All iSi carriers use Carbon Safe cradles and require no straps or tie downs, making them safe for carbon fibre bicycle frames.

Looking for fitment for your specific vehicle or caravan? Browse our Adventurers guide →