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NASA Technology

NASA-Inspired Airless Bicycle Tires Are Now Available (newatlas.com) 157

Posted by BeauHD from the never-go-flat dept.
The Ohio-based Smart Tire Company has started a Kickstarter campaign for its shape memory airless bicycle tires that were created in partnership with NASA. New Atlas reports: At the heart of each Metl tire is a Slinky-like spring that runs all the way around the tire. That spring is made of a shape memory nickel-titanium alloy known as NiTinol, which is described as being strong like titanium yet also stretchy like rubber. Importantly, when NiTinol is placed under pressure, it initially deforms but then goes back to its original shape. This characteristic allows the Metl tire to gently compress and rebound, providing a smooth ride just like a pneumatic tire.

The spring is encased in a poly-rubber material which forms the tire's transparent sidewalls and replaceable tread. According to the company, this setup incorporates only half as much rubber as a regular tire. Additionally, while the tread may have to be replaced roughly every 5,000 to 8,000 miles (8,047 to 12,875 km), the main tire should reportedly last for the life of the bike. For this commercial introduction of the technology, the Smart Tire Company is offering a road/gravel tire in size choices of 700 x 32c, 35c and 38c. The 35c model is claimed to weigh 450 grams (16 oz), which is around the middle of the weight range for comparable pneumatic tires.

And we're told that while this first version of the tire will be of a fixed firmness, future models may allow users to increase the firmness by pumping in more air. So they'll be semi-pneumatic, but they will still never go completely flat. Assuming the Metl tires reach production, a pledge of $500 will get you a set of two -- getting them retreaded should cost about $10. Complete aluminum or carbon fiber Metl-clad wheelsets are also available for pledges of $1,300 and $2,300, respectively. Potential backers should note, estimated delivery isn't until next June.
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NASA-Inspired Airless Bicycle Tires Are Now Available More

NASA-Inspired Airless Bicycle Tires Are Now Available

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  • Replacing air by a metal spring. Yeah OK.
    It is supposed to be "green" ? Nope.

    • Re: (Score:2, Redundant)

      by fahrbot-bot ( 874524 )

      Ya, but you forgot the part where you can add "more" air to these airless tires:

      ... future models may allow users to increase the firmness by pumping in more air.

      (sigh)

      • In this case, it might only be that you put in a few pounds to adjust the ride. Like how some cars can adjust ride height by pumping more air into the shocks or such.

        • I think people would be attracted to the idea that you wouldn't need a pump. Sounds like you do, though.

          • Re: (Score:2)

            by Jeremi ( 14640 )

            I like the idea of a tire that is still perfectly rideable even after it has been punctured by something on the ground; having to patch a tire by the side of the road isn't much fun, and I'd much rather just keep riding and do any necessary repairs after I get home.

            That's with all else being equal, of course; the critical question is what kind of performance and cost tradeoffs have to be made to achieve that ability, and whether it's still worth using after they have been taken into account.

            • I like the idea of a tire that is still perfectly rideable even after it has been punctured by something on the ground; having to patch a tire by the side of the road isn't much fun, and I'd much rather just keep riding and do any necessary repairs after I get home.

              That's with all else being equal, of course; the critical question is what kind of performance and cost tradeoffs have to be made to achieve that ability, and whether it's still worth using after they have been taken into account.

              I went to tubeless tires on my MTB, using Stan's race sealant. There is some maintenance involved, the sealant needs to be cleaned out and replaced occasionally, which is a messy job I pay the bike shop to do, but they work quite well. Drive over a nail and you hear a hiss for a few seconds and then it stops. Has saved me many trailside tube patching sessions.

          • Re:Misses the point (Score:5, Informative)

            by Ed Tice ( 3732157 ) on Thursday September 14, 2023 @12:31PM (#63848450)
            I take it you have never gone on a long bicycle ride and had to deal with changing a tire. A pump is the least of your issues. You have to carry spare tires and the tools to change it and a pump and it's a PITA. Many people don't have the skills to do it. Even if these are pressure-adjustable the value would be that you don't have to carry tire changing equipment or risk having to walk back thirty miles. Every cyclist who doesn't have a personal support vehicle behind them will be interested in these if they work.

            • No they won't.

              A patchkit, spare tube, plastic tire levers, 2X2 bit of canvas and a pump will cover anything ever likely to happen to your tires, and probably not weigh much more than a pair of these airless tires (which BTW, still require air pressure to adjust ride quality).

              Tubeless tires are an even better solution, being self sealing, and are now standard on all new bikes intended for back-country cycling.

              • I carry this exact kit and I've still gone on some long walks (including one where my friend's derailleur hangar broke) But there are *many* people out there who don't know how to change a tire and many more (like me) who don't practice and haven't done it so long that I might embarrass myself when the time comes.

              • Some people agree with you. In our experience over the last 3 years of market research, at least 90% are on the other side of the fence and would prefer a tire that simply doesn't require any of that. To each their own, of course.

    • It might make sense somewhere like the Moon, where air is at a premium and metals might be cheaper.

      It also would have the benefit of being naturally 'run flat', able to still function with more damage than an air based tire, or the downsides of run-flats.

      I think these would wear out just as fast - as it's tire tread. Unless you go back to "tubes" and just replace the outer tire?

      But pneumatic tires are a well developed technology.

      • You didn't even read TFS let alone TFA. The whole point is they can retread the tire cheaply instead of the entire thing being waste.

        • >> The whole point is they can retread the tire cheaply instead of the entire thing being waste.
          Re-threading bike tires ?
          Yeah. That is some industrial-grade B.S. right here.
          Hint: we do not re-thread car tires any more since ages because it is not deemed worth the effort, only truck and plane tires are re-threaded today.

          • That's the whole point, this changes the entire equation. All you need to do is refresh the consumable part instead of replace the entire tire, on top of the benefits in safety and reliability.

          • You are completely out of your element and don't know what you're talking about.

            The whole point of one of these tires is that you buy the tire and it lasts the lifetime of the bike, because you can separately buy tread that affixes in some way to the much stronger tire that also is basically a run-flat without the downsides of a run-flat. A "retread" would essentially be buying a new circle of just tread from the bike shop or whatever, going home, removing the worn out tread and affixing the new one.

            It's n

      • Ever since I swapped to kevlar outer tires, flat tires have been a thing of the past. To me, that problem has already been solved. I'm sure they're doing their best trying to hype an overpriced product that does not add much, if any, value. Alright, I still have to check the pressure once or twice a year, not having to do that would be a big gamechanger (sarcasm).
        • Are you riding kevlars and not carrying tire tools/pump/spare tube? Or do you still carry the extra equipment.

          • That is the real question. If they are riding long distances without a patch kit or spare then they are risking a long walk home no matter how dependable their Kevlar tire is.

            Once these come down to $200 Canadian a set I'm probably going to get a pair, right now they are in early adopter pricing and the economy of scale for production has not kicked in.

          • I don't carry a repair kit. Thousands of km and not a single puncture. Sorry for the late reply.
    • What are tire pumps made of?
  • I can see people putting LEDs inside the tyres, that would look great and be good for visibly too.

    • Re: (Score:2)

      by stooo ( 2202012 )

      It looks great, and is illegal.
      Like putting random lights on vehicles.
      Vehicle lighting is precisely regulated for a reason.

      • I bet you are fun at parties.

      • No, they're not illegal.

        https://www.way.com/blog/are-c... [way.com]

  • How long does a traditional high-quality bike tire last? Car tires can last 20K, 30K, 40K miles... so how long will a bike tire function?

    Given this tire uses half the rubber but needs to be re-treaded every 8K miles - that's an important part of the equation. If a traditional tire lasts more than 16K, then this may actually require more rubber overall.

    • A few 1000km for a cycling tyre, the types I use are optimised not for pure race performance but usability, puncture resistance and such like.

      I ride my bike tyres until they fail - not what the manufacturers recommend but they have a vested interest. The front lasts a lot longer than the rear: less weight, no traction load, and it never skids.

      I always feel I'm getting a raw deal, a quality bike tyre costs $40 or thereabouts, you get a car tyre for twice that, with maybe 20x more material on it!

      John Bo

      • I always feel I'm getting a raw deal, a quality bike tyre costs $40 or thereabouts, you get a car tyre for twice that, with maybe 20x more material on it!

        Wow...where do you get a car tire for only $80 each?!?!?

        And what brand, what rating is it? What size?

        I don't think I've ever seen a tire that cheap.

        • Walmart [walmart.com]. Arroyo eco P195/65R15. $51.04. 91H for the temp/speed rating. You actually have 6 options under $60.

          A bit of googling [sizemytires.com], that's a bunch of Audi, Chevy, Honda, Mercedes(wtf with cheap tires for them?), toyotas, VW, and volvos. It's basically a size common for standard sedans.

          At that price, you can pay for mounting, lifetime balance/rotation, and get the road-hazard warranty and still stay under $80.

          And as I'm typing the above, I realize it's because it sees my car. Changing to my truck bumps the

          • At that price, you can pay for mounting, lifetime balance/rotation, and get the road-hazard warranty and still stay under $80.

            Wow....that's intesting. Thanks for the info.

            I think all my tires have been in the $140-$190 or so range? Its been so long since I last bought.

            I know my Z5 corvette that had the run flats...THOSE were $$$$$. But I put that up as specialty vette tax.

            But well over $100 each to me has always been normal. I guess since mine were all speed rated, etc..?

            • Yes, you're paying for the speed rating, your tires are probably wider as well, for better gripping. Combine the better manufacturing for better heat handling for higher speed driving, along with a less common size, and your price easily balloons.

              The tires I quoted are for people who view driving as a task to be done as cheaply as possible.

              The last time I bought tires for my car(which takes the cheap size), I still paid better than $100/tire. Because I got *good* tires that offer superior handling than th

      • I ride my bike tyres until they fail - not what the manufacturers recommend but they have a vested interest. The front lasts a lot longer than the rear: less weight, no traction load, and it never skids.

        I like to swap the front and rear tires of my bike when the rear starts getting worn for that reason. Prolongs their use.

    • Re: (Score:2)

      by DrXym ( 126579 )

      I've seen this too with airless car tires [michelin.com] which look like regular tires with open sided sort of stiffened rubbery spokes to act as the "pressure". Every now and then there will be a puff piece about them touting how they resist punctures and don't need pumping up and how they'll be eco friendly because less tires replaced due to punctures. But they always seem to skirt over such factors as cost, material, wear, performance, durability, and impact on fuel efficiency.

    • How long does a traditional high-quality bike tire last?

      Depends if you like doing skiddies.

    • Puncture vines give bike tires a five minute life time here. This might be an alternative to filling the tire with Slime. That doesn't do much for the ride.

      https://en.wikipedia.org/wiki/... [wikipedia.org]

      • Re: (Score:2)

        by Reziac ( 43301 ) *

        Yeah, here it's also goat heads vs bike tires, feet, animals, and anything else neither metal nor less than an inch thick. Regular bike tires last from here to the corner and back. Puncture-proof bike tires would be hailed as a miracle.

        I managed to eradicate the fuckers on two different rural properties by going into hunter-killer mode every time I saw those little rows of leaves or pretty yellow flowers, and religiously yanking them up by the roots. Now all I get are what the deer bring me, and from a few

    • Re: (Score:2)

      by dfghjk ( 711126 )

      No one gets 8K on a set of bicycle tires. For touring, the limit may be that high at most. For other kinds of cycling it is far less. Mountain bikers often replace their tires multiple times a year.

      The amount of rubber consumed doesn't matter at all, the purpose of the retread is to spread the absurd cost over a lifetime of the bike.

    • Re: (Score:3)

      by Dusanyu ( 675778 )
      Depends on the rider how they ride riding conditions there weight etc even the type of bike is a factor. for example if you put Standard bike tires on a electric bike, Schwinn Wizzer, or Zeta Kit the tires will probably last all of 300 Miles. As far as a standard push bike I can give anecdotal evidence of how long they last under the conditions of long range bicycle Touring. in my Year i took between High school and university i took a Bicycle tour between the east and west coast of the US (roughly 2,70

    • As someone who rides close to 16k km a year, a high performance tire (say Conti 5000) lasts around 5000km. That's assuming there's no damage, which also occurs quite a bit. I've had tires with just a few 100 km and a slash from road debris rendered useless. This might be less of an issue with this design as well.

    • Only a person who does not ride a bicycle would compare a bicycle tire to a car tire. Bicycle tires are designed to be light since the force required to spin the wheel is proportional to the mass of the tire. A heavy tire impacts the energy a rider has to exert to get moving more than a heavy bike because of the radius multiplier on the inertia. The bicycle replacement tire market is almost 1/7th that of the entire bicycle market in the US. Tires cost a lot less than bicycles, so people clearly go throug
    • I doubt the point of this is to require less rubber. But if it's similar rubber to what's used in existing tires, likely the replacement period will be similar. The point is not to have to carry tire changing equipment.

    • Re: (Score:2)

      by eepok ( 545733 )

      I ride a touring bike with robust touring tires and ride 99.99% of the time on asphalt. I normally replace my tires and chain annually and ride around 3,000 miles/year.

      Oddly enough bike tires contain *very little* rubber as compared to vehicle tires. Depending on the type of tire, there may be equal amounts of thread, fabric, metal, and plastic in there. It's why few automobile tire recyclers are willing to take bike tires. There's just not enough rubber in them.

  • "NASA inspired" (Score:4, Insightful)

    by DrXym ( 126579 ) on Thursday September 14, 2023 @03:22AM (#63847330)

    When you see weasel words, treat everything else with a massive grain of salt - "long believed to help with the treatment of backache", "a source of prodildosterides (TM) for shinier hair", "naturally low in sugar", "derived from plant extracts", "up to 90% (*) off!!!", "voted car of the year (*)", "helps you lose weight as part of a calorie controlled diet".

    • Re: (Score:2)

      by mjwx ( 966435 )

      When you see weasel words, treat everything else with a massive grain of salt - "long believed to help with the treatment of backache", "a source of prodildosterides (TM) for shinier hair", "naturally low in sugar", "derived from plant extracts", "up to 90% (*) off!!!", "voted car of the year (*)", "helps you lose weight as part of a calorie controlled diet".

      Almost enough to make you wonder why other countries have advertising standards.

      • Re: (Score:2)

        by HBI ( 10338492 )

        Controlling narcissist marketers is a talent the US hasn't quite acquired.

        • Re: (Score:2)

          by mjwx ( 966435 )

          Controlling narcissist marketers is a talent the US hasn't quite acquired.

          I meant more along the lines of punishing misleading advertising statements, but that is also a very good point.

    • Re:"NASA inspired" (Score:5, Informative)

      by Anubis IV ( 1279820 ) on Thursday September 14, 2023 @08:46AM (#63847866)

      I understand your point, but it seems misguided here. They use stronger wording in the summary and the body of the article itself, such as “made in partnership with NASA”. Their Kickstarter then adds that “The SMART Tire Company has a Space Act Agreement with NASA and an exclusive license to further develop and commercialize this superelastic tire” and that they were recognized with NASA’s R&D 100 Award.

      Also, NASA itself has talked about them at nasa.gov: https://technology.nasa.gov/pa... [nasa.gov]

  • fancy space age tech, but air in a pneumaic tyre, is still better, isn't it.

  • no issues with low temperature? (Score:4, Interesting)

    by sonoronos ( 610381 ) on Thursday September 14, 2023 @04:56AM (#63847420)

    One of the useful characteristics of Nitinol is its martensite-austenite phase change characteristics, which give it its well known "shape memory" and its "superelasticity"

    The issue as it pertains to bike tires is that most nitinol alloys exhibit this R-Phase change at temperatures that are generally experienced in environments that you would ride a bicycle, and low temperatures - winter temperatures - will adversely affect the mechanical properties of the tire.

      Depending on the composition of the wire in the tire, the stiffness of the tire's wire alloy could be reduced by less than half just by riding in winter, and could deform very easily. Easily enough to be unusable.

    If the nitinol being used in this tire is formulated to exhibit a higher R-Phase temp, then it stands to reason that stainless steel would probably be a better choice for the wire than nitinol, as I can't think of any property of nitinol that would benefit the application over any other traditional material.

    • Re: (Score:2)

      by dfghjk ( 711126 )

      "Depending on the composition of the wire in the tire, the stiffness of the tire's wire alloy could be reduced by less than half just by riding in winter, and could deform very easily. Easily enough to be unusable."

      And don't forget, 90% of the load on a bicycle tire is rider weight. There is no way to determine what the stiffness of the tire needs to be.

      These things will never be anything other than an abject failure. THE MOST IMPORTANT feature of a bicycle tire is rolling resistance, not how often you in

    • Nitinol was in the news quite a bit about 15 years ago with the media calling it "muscle wire". I was intrigued and bought a small spool of it to play with. I found that using electricity made for very quick transitions. However, using temperature change instead of electricity made transitions much slower. I don't understand how Nitinol in a bike tire is going to useful without active heating/cooling or electricity applied.

    • Re:no issues with low temperature? (Score:4, Informative)

      by thegarbz ( 1787294 ) on Thursday September 14, 2023 @11:31AM (#63848246)

      The issue as it pertains to bike tires is that most nitinol alloys exhibit this R-Phase change at temperatures that are generally experienced in environments that you would ride a bicycle, and low temperatures - winter temperatures - will adversely affect the mechanical properties of the tire.

      NiTiNol Specifically has the R-Phase change tuneable between -150 and +350C during manufacture. NASA specifically certified their NiTiNol tires for use on Mars missions where it will be subjected to -80C constantly (though ended up going with an Aluminium tire instead on their recent rovers). You're not going to be cycling at that temperature in winter on earth.

      You're right, depending on the composition of the wire in the tire is may deform, but depending on the composition of the material in any other tire it may break too. Composition is an engineering variable to control, nothing more.

      I can't think of any property of nitinol that would benefit the application over any other traditional material.

      Traditional wire mesh tires require a bump guard as they can only handle a certain deformation before breaking due to plastic deformation, and precisely why NASA stopped using wire meshes after the moon landings as the bump guards wear out. NiTiNol increases this tolerance dramatically to the point where not only is a bump guard not required, but should damage occur it would also be easily repairable simply by applying heat.

      You may not be able to think of why this would be better, but the clever scientists who specifically developed this to address the shortcomings of other materials certainly can.

      • Letâ(TM)s assume for a moment that these tires are made from an alloy that is formulated with a transformation temperature well below 0 degrees C.

        Now you are operating the wire as a tire as an austenite only . Letâ(TM)s assume you are operating an alloy where SIM properties are uniform and useful across a wide variety of temperatures, say between 0 and 50C, where cyclists would use the tire.

        Nevertheless, the superelastic properties of this supposed wire will now have recoverable strain but a modul

  • ...is a scam.

    • ...is a scam.

      It hasn't been for me..I've gotten some really cool and useful stuff for a reasonable price on there.

      I've gotten some cool lenses...macro flash and lighten set ups, a really fantastic macro book this guy put out, coming soon, an instax film back for my Hasselblad 501 CM camera...anamorphic lens sets (I think you see a trend here).

      The point is...some of these were pretty high dollar, but I found them to be a great bargain and the majority of them come in on time that I've experienced.

      There's

  • Saving rubber when the tire is $500 is just greenwashing.

    In the modern economy all earnings come from fossil fuels to a large degree.

    To earn $500 costs far more in resources than a pound of rubber can save.

    And then let's talk about mining and forging nickel and titanium.

    I hate fake environmentalism. Among the most wicked of lies!

    I don't buy new products from known liars - duh!

  • Currently, Earth doesn't have the same environmental conditions as the Moon. I can't think of any practical reasons for this technology other than separating cash from wallets.
  • If these Nitinol tires have less rolling resistance than conventional pneumatic tires, they will become a must-have on the bicycle racing circuit.

  • NASA developed the wheel technology, in partnership with commercial partners. This kickstarter campaign is attempting to use the output of that partnership, they were not part of it.

    • The SMART Tire Company has an exclusive commercial license, a Space Act Agreement with NASA to co-develop the tech, and employs one of the original inventors. All of these being publicly verifiable facts through NASA.gov and the patent office.

      • None of which facts are the same as the SMART company "creating the technology in partnership with NASA." It's wordsmithing. Sure, there's a license, and sure an original inventor was later hired by the company. That doesn't mean the company created the technology in partnership with NASA. NASA developed it, the company came later and licensed the tech. That is a more honest way to characterize the relationship.

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