With solid tyres never really catching on for roadies, could this new airless metal invention using tech straight from NASA's labs consign punctures to history? The start-up SMART Tire Company says its new METL bicycle tyre uses the same airless shape memory (SMA) tyre technology that NASA invented for use in outer space on Mar Rover missions, and "still rides smooth” despite being made of a light and flexible metal.
Made from advanced, lightweight materials known as NiTinol+, the METL tyre promises to be elastic like rubber but is as strong as titanium. Basically, it holds perfect shape memory without going flat, eliminating the need for ever replacing tubes or tyres. The SMART Tire Company says METL could completely transform everyday bike rides by turning tyres into a permanent part of the bike, with no regular maintenance needed.
The original Superelastic Tire, developed by NASA, is an airless tyre that eliminates the possibility of punctures or running under-inflated, as to avoid failures when stuck in space with no one nearby to fix a flat.
The SMART Tire Company , an acronym for Shape Memory Alloy Radial Technology, has brought this space technology back to Earth for new applications and to “revolutionize the global tyre industry with a new way of thinking for all vehicles, from bicycles and electric scooters, to automobiles, trucking and aerospace.”
The Smart Tire has a patented load-bearing design that is said to take advantage of the unique properties of shape memory alloys that NASA used.
“These special metals can expand, contract, bend or unbend at a very rapid rate (like rubber) and with so much force that it can move heavy objects. Even with extreme deformation, the tyre regains 100% of its shape through phase transitions at the molecular level,” says the brand.
The SMART Tire Company explains that many issues with pneumatic tyres are addressable by its technology, including lower weight, less rubber, higher load not governed by tyre pressure, zero flats and a significant reduction in waste.
The METL tyres are eco-friendly as it uses long-lasting materials. “Developing a long-lasting tire for the circular economy is a core goal for our company, to make a positive, more socially-conscious global footprint.”
These aren't the first airless tyres and probably won't be the last, with automotive tyre firm Bridgestone being one of the more notable examples to reveal a concept in recent years. Showing off versions for motor vehicles and bicycles, Bridgestone said it intended to start selling the tyres in 2019 when we published our article in 2017; although to our knowledge, and scanning Bridgestone's website, that never materialised.
The SMART Tire Company says METL tyres will be available from 2022 - you can find its website here.