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Could these NASA-developed 'space-age metal' bike tyres make punctures a thing of the past?

Using the same tech that NASA invented for Mar Rover missions, SMART Tire Company says its product could eliminate the need to replace tubes or tyres

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. 

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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.

SMART Tire Company METL 1

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.”

SMART Tire Company METL 3

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.”

> How green are your bike tyres? What the big brands are doing, and what YOU can do to help

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

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10 comments

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Xenophon2 | 2 years ago
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Setting aside the price elephant, the main issue would be grip, especially in the wet.  And the racket it's bound to make when riding over hard surfaces.  What's the point of the exercise if it regularly needs to be re-coated in rubber, which may be a lot less resistant to delamination under periodic plastic deformation of the metal.  I can see this being used if ever someone wants to cross Antarctica on a bike but for regular applications...no way.

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froze | 2 years ago
0 likes

That's all well and good but there was no word on how long the Metl tire would last, nor the cost of the tire, nor any word about how good the traction is on dry and wet pavement.

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Global Nomad | 2 years ago
1 like

no mention of how they allow for variable load and equivalent of changing tyre pressure. On the mars rover they are designed for a fixed and known load, on  abike people vary as does what they carry and weather conditions. Does seem useable/useful for some applications but not sure its one for bicycles...

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mdavidford | 2 years ago
1 like

Unfortunately, your bike computer will run with about a 13 minute delay (not that GPS will work anyway), and you won't be able to travel anywhere during the hours of darkness.

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Secret_squirrel | 2 years ago
2 likes

Its worth bearing in mind that having a tyre wear may be a preferable choice to having the road wear.  Not sure that it is or not but I'd like to see some data on it.

Also data on friction/rolling resistance/handling in the wet/temperatures etc etc

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andystow replied to Secret_squirrel | 2 years ago
1 like

There would still be rubber between the metal and the road.

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fwhite181 replied to andystow | 2 years ago
6 likes

Buried in the small print on their website is a bit about coating the real world version of the tyre in a "new, formulated poly-rubber material, for the longest-lasting tread and grip, for all weather conditions". Also known as...rubber. And as almost every cyclist knows it's a trade off between grip and long-life, so if they last for ages they'll probably grip like a gatorskin, and if they grip like a GP5000 the rubber will last...like a GP5000. Unless they've also invented some hitherto unknown chemistry the actual grippy bit will be much the same as every other bike tyre! 

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fwhite181 | 2 years ago
2 likes

Probably not.

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fwhite181 replied to fwhite181 | 2 years ago
1 like

But in more seriousness, they look like a potentially viable idea for HGVs/cars where tread-depth is measured in centimetres and a tyre would only need to be re-rubbered every 20-30,000 miles. For bikes I suspect they'll be quite heavy compared to the lightest, not quite as supple as the best, eye-wateringly expensive, and if the company goes bust there'll be no way to get them re-rubbered and all of a sudden you have a very expensive single-use metal tyre.

I can see applications for hardcore middle-of-nowhere touring cyclists, but probably not for roadies. For the kind of road/race cyclist that would get value for money from a re-treadable tyre (e.g. rides 10,000+km/year) the performance would have to be up there with the very best of conventional tyres. Most cyclists probably find that a standard rubber tyre is already a lifetime tyre.

I'd love to be proved wrong though. Punctures are a pain! 

Avatar
massive4x4 replied to fwhite181 | 2 years ago
0 likes

fwhite181 wrote:

But in more seriousness, they look like a potentially viable idea for HGVs/cars where tread-depth is measured in centimetres and a tyre would only need to be re-rubbered every 20-30,000 miles. For bikes I suspect they'll be quite heavy compared to the lightest, not quite as supple as the best, eye-wateringly expensive, and if the company goes bust there'll be no way to get them re-rubbered and all of a sudden you have a very expensive single-use metal tyre.

I can see applications for hardcore middle-of-nowhere touring cyclists, but probably not for roadies. For the kind of road/race cyclist that would get value for money from a re-treadable tyre (e.g. rides 10,000+km/year) the performance would have to be up there with the very best of conventional tyres. Most cyclists probably find that a standard rubber tyre is already a lifetime tyre.

I'd love to be proved wrong though. Punctures are a pain! 

I could see this potentially working like a chain that you need to periodically lubricate. Potentially this could work by the user painting a coat of rubber on it every few thousand miles when a coloured strip appears.

The other plus side is that you could change the compound by season or use case.

 

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