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CHECK THOSE TIRES, SIR?
GRANDPA WILL have to explain that “service station” attendants used to ask whether you wanted your tire pressures checked during refueling, this along with giving the windshield a polishing.
These days “service” typically has the prefix “self” attached. What’s more, news from SAE International is that GM is partnering with Michelin to bring an airless wheel into widespread automotive use.
Closeup of Michelin’s airless Uptis mounted on a Chevrolet Bolt EV. Image from SAE International Automotive Engineering, July/August 2019.
Terry Costlow gives details in “Michelin, GM Partner on Airless Wheel for 2024,” SAE International Automotive Engineering, July/August 2019: “This novel structure, which has been long in development and is covered by about 50 patents, is made with aluminum, rubber components, and resin-impregnated fiberglass.”
To be called the Uptis (Unique Puncture-proof Tire System), this new automotive application broadens the use of the Michelin X Tweel, already marketed for a variety of off-road and commercial vehicles. Included are all-terrain vehicles, garden tractors, golf carts, and industrial skid steer loaders.
Costlow writes, “The airless structure eliminates the possibility of blowouts, improving safety and ensuring that drivers won’t be stranded by flats.” Michelin’s Eric Vinesse is quoted estimating that 200 million tires annually are discarded because of punctures.
The need is greater in other world markets than in North America. As an example Costlow observes, “North American drivers typically have tire punctures every two or three years, while punctures occur every six to eight months in China.”
Back in May 2018, Tire Technology International cited availability for vehicles such as the BRP Can-Am Defender, Kawasaki Mule, and Polaris Ranger. The Michelin X Tweel UTV 26x9N14 is rated for 60 km/h (37 mph) and 1300 kg (2866 lb.). Various bolt patterns are available, a typical Tweel priced at $750 each.
The Michelin Newsroom offers details on other Tweels, including its SSL All Terrain designed for skid steer loaders. Michelin cites advantages beyond the evident damage resistance: These include “exceptional operator comfort, reduced operator fatigue, improved productivity, and longer wear than standard pneumatic tires.”
Details of the Michelin X Tweel SSL. Image from Michelin.
THMotorsports lists the Tweel SSL All Terrain R17 for $956.35 each.
A Michelin Uptis mounted on a GM Bolt EV. Image from ctvnews.ca
SAE’s Costlow notes that the Uptis weighs about 5 percent more than conventional tires, this added weight being offset because no spare tire is needed. Still to come are government standards and regulations for road use of non-inflatables. With an intended 2024 introduction, it’s too early to set prices for road-going automotive applications. ds
© Dennis Simanaitis, SimanaitisSays.com, 2019
Simanaitis Says 
Dennis,
My uncle was the car guy, my dad was the architect and my great-grandfather invented and patented the pneumatic tire!!
Erin
Although the multi-ribbed architecture theoretically could make such a tire laterally stiffer than a sidewall in flexure, it looks like the lateral performance of these wheels would be poor. I don’t think that these will be replacing P-Zeros or PS-2s anytime soon. Possibly a design with ribs and sidewalls might though.
A vandal could slip a long piece of rebar through the tire structure, and the resulting damage would be spectacular. I’d do a full walk-around any time I parked in a sketchy neighborhood.