This property meant that nitinol could be used in NASA rover tires, as they could withstand freezing temperatures, won't go flat, and could envelop obstacles all the way down to the rim without plasticizing the material.
Nitinol can and has been used for various other purposes, such as constructing F-14 fighter jet wings, developing flexible eyeglass frames, or in the medical field to make stents. The METL bicycle tire will be the first consumer product to use nitinol, and its maker says the tires will last a lifetime, never going flat. Such a claim is hard to ignore.
The Smart Tire Company has a Space Act Agreement with NASA and an exclusive license to develop and commercialize the superelastic tire. The SMA tire technology has been in development for over 12 years, with more than $10M in government funding and research.
If you're familiar with Kickstarter, you know the projects there can be a hit or miss. These projects often run into delays and missed deadlines, and many end up not even being finalized. Moreover, when you back a product on Kickstarter, you're not necessarily buying it, as the platform's policy states that Project Creators may cancel or refund a pledge at any time for any reason, and they do not have to fulfill the reward. That doesn't mean you can't find genuine and successful projects - I've personally backed a project on Kickstarter, and I'm happy with the product I received.
With this disclaimer out of the way, let's take a closer look at the METL tire. The product aims to make cyclists' lives easier by eliminating the possibility of flat tires. Of course, that's already been done with airless tires, but they come with a few downsides, such as a rougher ride and increased rolling resistance.
METL tires feature a spring made from Nitinol that runs around the tire. It's encased in a poly-rubber material forming the tire's transparent sidewall and replaceable thread – the company claims this setup uses half as much rubber as a regular tire. As more than a billion tires reach their end-of-lie per year, it's refreshing to see products that keep sustainability in mind.
Smart Tire Company will offer road/gravel METL tires in size choices of 700 x 32c, 35c, and 38c, with medium-low rolling resistance. Moreover, they're manufactured in the United States and tip the scales at around 450 grams (almost 16 ounces).
Smart Tire Company says that its tires are "DIY easy install" onto most common gravel or road bikes. Furthermore, they're designed to offer a lightweight, smooth ride with superior handling and durability, as well as increased traction compared to typical air-filled tires. Believe it or not, its maker claims it has even shot a bullet through the tire and kept riding.
If the technology does reach production, delivery is scheduled for June next year. As of now, 140 backers have pledged $73,265 (€68,672), significantly surpassing the project's $25,000 (€23,433) goal. In fact, it took just 18 minutes for the funding goal to be met. Plans for the Smart Tire Company include developing wider METL tires for MTBs and e-bikes.