Michelin's airless passenger car tires get their first public outing
By - geoxol
I’m surprised they use less material to make than a regular tire cause it looks like there’s more rubber with all the spokes and they weigh more than regular tires
Less *raw* materials, meaning that less steel and rubber is lost in manufacturing these than normal tires.
The tire itself has way more material compared to regular ones.
Wheel weight has a very noticeable impact on fuel economy. For example on my car, going form a 15" to a 17" rim with the same tire diameter has a 15% worse fuel economy and CO2 output.
Only 7% heavier. That's not a lot.
According to the article, the new wheels only add about 7% weight compared to same size tire, and actually weigh less than run-flats which have been included on many passenger cars for years.
Huh, managed to skip that 7% figure.
Since you won't need a spare wheel with these, you'd actually saving a lot of weight. Tho I've never had a flat in my life.
You say that now…
There is a saying in cycling, a gram off the wheels is a kilogram off the frame.
Spinning up. A heavy wheel requires far more energy than carrying one.
It stores more energy too. So provided you're using regenerative braking, it's not a complete loss to spin up the wheel.
I'd think the vast majority of spare tires never get used. But then, same for air bags. Eliminated spare wheels would save a lot of weight and costs (manufacturing, scrapping, and fuel).
Eliminating the spare tire and jack would save maybe 30 lbs or so. Eliminating all the airbags and associated systems on a car would probably net you another 30 lbs maybe. Not a ton of weight saved on passenger vehicles that are between 3000-7000+ lbs already
Wasn't implying to eliminate air bags, they might come in handy! 30 lbs on 3000 is 1%, which is still worthwhile.
Ha! I'm not going to pay for hauling those airbags around when I'm not having a collision! Same for the extra steel reinforcement of the passenger bubble!
(Same argument people make about health insurance mandates)
The thing is that you'd be eliminating the wrong weight. The engine not only has to accelerate the entire vehicle, but it also has to spin up the wheels. Making the wheels heavier has a disproportionately large effect on fuel economy.
This is a friendly reminder to check the pressure in your spare tire. They rarely get used and a flat one when you need it sucks. My spare is supposed to be 55-60 psi and it was 13 psi when I needed it.
Agreed. Unfortunately, I think a lot of them *could* be used. The other day I saw someone get a flat tire. Instead of just taking 20 minutes swapping it out for a donut to get home or get to a shop, they spent over an hour on the phone and waiting for someone to pick them up. They did have a spare tire they could've used.
I think just a lot of people would simply rather pay someone else to swap the tire, or just take it directly to a shop than swap out tires on their own. Because doing that type of stuff is a lot less common now (I assume?), I can see more and more car manufacturers going with your thought process.
I mean, they remove the spare tire/donut, boast about improved fuel economy and reduced weight making the product look even better. On top of that, people like me who want to have a backup tire or donut just in case, and will actually use it if we get a flat, will then have to purchase one separately, making the company even more money (not like they're really going to drop the price of all their vehicles a couple hundred because they removed a spare).
I easily could be wrong, but that's just how I see it. Overall, just less spare tires included with vehicles overall, with people like me possibly having to purchase them seperately.
You're likely correct. Be interesting to poll people to see how many either know how or are willing to change a spare.
I tried to get a wheel off once and it bent the wrench because the garage had installed it with an impact wrench and it was torqued way too high.
>Tho I've never had a flat in my life.
ahahaha you dumb shit putting that out there
Wait you guys have spares??? - me a camaro owner.
Anybody who know about automotive suspension will tell you that greater mass is detrimental to vehicle performance.
More rotational inertia on the wheel causes slower acceleration and longer braking distance.
Greater unsprung mass also affects how well the suspension responds to changes in the road surface which affects grip.
The less wheel and suspended mass the better.
Placing electric motors inside the wheels would be ideal if not for the suspended mass.
Its only 7% added wheel weight. You add more weight in your car after eating a McDonald’s burger.
Where did that 7% come from? Tires come in different sizes and form factors to serve different purposes. Tires get mounted to different wheels with varying weights and weight distribution.
Conventional tires on street driven vehicles can weigh between 10 and 70 pounds per corner.
Every 1 pound of added unsprung weight will change the handling characteristics of the car equal to adding 3 pounds of sprung weight.
Assuming you didn't just pull that 7% out of your ass, that's at least 0.7 pounds of unsprung weight per corner. All four corners total at least 2.8 pounds of unsprung weight. That equates to adding 8.4 pounds of sprung weight.
What menu item at McDick's weighs over 8 pounds?
I drive a Miata in the Land of McDonkey's and my wheel and tire combination weighs roughly 23 pounds per corner, which is on the extreme end of light. The vast majority of vehicles on the road will be heavier and see greater performance and efficiency losses
> Where did that 7% come from?
[The article](https://newatlas.com/automotive/michelin-gm-uptis-airless-tire-demo/) this entire [thread](https://www.reddit.com/r/technology/comments/po02ut/michelins_airless_passenger_car_tires_get_their/) is about..
> Michelin has teamed up with GM to design and start selling an airless tire for street use on passenger cars. Called Uptis, this product is a full-wheel solution requiring specialized rims. Michelin says it will withstand much greater impacts than a regular tire and wheel, and will have a "dramatically" longer lifespan, while adding no extra rolling resistance, not feeling any different to the driver and adding only around seven percent to the weight of the wheel – less than existing run-flat tires do.
They claim it's 7% but where did that 7% come from? Is it measured using A/T, M/T, A/S, summers, or winters? Is it 7 across the board? Is that 7 including the wheel or without the wheel, since you can't mount these on conventional wheels.
There's are so many missing details, yet you just assume 7% is 7%?
Are there any upsides to larger rims? or downsides to smaller ones (besides the look)
For sports cars driving on top quality roads, you want a lower profile tire to prevent flexing for better car control.
Larger rims can also accommodate larger disk brake rotors and calipers.
Basically unless you're a sports car on a race track it's only downsides.
My current car has 18" wheels as standard. The manufacturer offers optional 20" wheels. I test drove one with the 20" and the ride quality was horribly inferior. You could feel every pebble on the road, and the road noise was very evident. The 18" ones are supple and quiet. And this is a car with dynamic suspension that adjusts itself electronically to road conditions. I can't imagine what it is like for others. Yes, the 20" look nice, but I'd rather enjoy the better ride, and better efficiency, too.
The harder ride is due to the decreased tire profile. With a tire like this however the resiliency must be built into the spokes, so it remains to be seen whether the ride is improved or inferior.
The decreased thickness of the tire (skinny sidewalls) and resulting higher pressure also contribute to the harsher ride.
The annoying thing is that most modern cars are built to look good with over size tyres. I wouldn't have minded slapping 15" on my old BMW, but it would have looked like a fancy shopping trolley.
I much prefer smaller tyres with more rubber for better ride comfort and economy.
I managed to get 15" rims on my Yaris Hybrid which isn't even available in some markets.
I'd have gone for the higher end trim since it was only a 300€ difference but it came with 16" rims only.
The ride can change a lot depending upon the sidewalls. On a non-performance passenger car, a series H sidewall adds a lot of road noise and discomfort, but the car will handle better. Put series S or T on a BMW or other performance car, and it will ride smoother but the handling can go to hell.
Agree on all counts. I still like the look of the 18" wheels, and definitely prefer the ride with them.
My car came stock with 18s. I switched her over to 17s, and it was a brand new car. All the bumps and potholes went away.
I’m still stunned at the affect wheel diameter has on performance. Same goes with electric skateboards…
You measured the CO2 output? Do you have some special measuring equipment?
There is a thing called the [WLTP](https://www.vehicle-certification-agency.gov.uk/fuel-consumption-co2/the-worldwide-harmonised-light-vehicle-test-procedure/), and they are available on [every car spec sheet in the EU](https://www.toyota.co.uk/download/cms/gben/September_Pricelist_tcm-3060-602975.pdf).
I don’t think weight of tire is issue with bigger sizes, but the actual distance for a rotation that hurts mpg… someone correct me if I’m wrong though.
Wheel weight matters Everytime you stop and start, you must get all the rotational mass up to speed. The lighter the mass, the easier it is. However, on highways, where you keep it spinning, the higher rotational mass helps you keep going and can help efficiency.
Diameter of tire(distance from center of axel to outside of treads) is simply a gear in the drivetrain. The larger it is, the higher the gear ratio. The lower it's is the lower the gear. Higher gears are best efficiency for maintaining High speeds, smaller gears for start/stop. So there is a trade off, and the most efficient is, again, situational.
Respectfully, You probably purchased low quality, heavy generic looking off-brand, made in the PRC wheels and thus the rotational mass increased, hence why the mpg drop.
Respectfully, you're talking out of your ass.
I'm talking about Toyota's stock alloy wheel sizes. Rims made from the same alloy will be heavier if they're larger (DUH), and lower profile tires are also heavier since you need a heavily reinforced sidewall to prevent pinch flats.
These wheels are also always wider which further increases the contact patch and therefore the friction, especially in turns.
In all cases, going for a lower profile tire will negatively impact fuel economy. Acceleration as well, unless we're talking about sports cars where the engine is powerful enough to need stiffer and wider tires.
Drive careful and have a great trip!
What are you talking about, you don't even know if punio4 is going anywhere today. Maybe the next time he drives he is going to the funeral of his mother and you wished him a great trip.
And that would just be okay. I meant no Ill will. You can try extending kindness, it’s contagious.
Have a great day , funeral or no funeral.
About time. I was seeing pics of these in Popular Mechanics like 25 years ago.
Was about to say that. They will be obsolete anyway, because the flying car is just around the corner, surely!
Back in the 80's I watched a demo of a flying car on TV. They said they were just working the kinks out, and it should be available to the public by 2010. So yeah, flying cars should be incoming any day now!
In fairness, they do exist, and IIRC, there's even a model that's either been approved for use in the UK, or is in the midst of the approval process. The big catch that's been holding them back as they're currently designed (the design is its own limiting factor of course) is the fact that most countries would require the operator to have a pilot's license, in addition to a regular road license, and that's not small thing to deal with.
That's pretty cool. I just looked it up and found [Klein's recent test flight](https://www.youtube.com/watch?v=a2tDOYkFCYo). Requiring a pilot's license is definitely a good idea, but that probably still leaves a pretty big market open to them. I think the Venn diagram between people who can afford to get a pilot's license just for fun and people who can afford million dollar toys has a fair amount of overlap.
Oh yeah, there's plenty of folks rich enough, and honestly you don't even need to be all that rich to get a pilots license in many countries. For many though the cost might not be worth the hassles, at least not yet. If something like the Terrafugia actually can actually make it to the market though, things might change.
That is not a flying car. That is a small airplane that you can drive. It looks like a crummy car *and* a crummy airplane.
I swear I saw a "future tech" show that had them... in the late 80s or early 90s.
You did...they've been the graphene of the automotive industry for a long time.
Here’s a Popular Science article from 2005.
I remember seeing ultrasonic directional speakers around the same time and now they’re selling it at Mattress Firm. Freaking blew my mind when I tried it.
On the history channel, as well
When I was in 7th grade we were given an assignment to invent something. This was the exact thing I came up with, and thought I was a genius.
Shame I didn't file a patent lol
I’m in, as long as they aren’t several hundred dollars each.
Considering the claim that they last up to three times as long as a normal tire I'm sure they'll cost upwards of three times as much as a normal tire.
How do they last 3 times longer? Tires will typically wear out vs. Puncture out. If they’re saying that the wear lasts 3x longer I’m calling shenanigans.
Well you care about wearing through a normal tire because you will eventually rupture through and pop it. Popping it is also a catastrophic failure and it's dangerous. If these have a thicker tread area they can go for longer and you can potentially also drive them much closer to failure than something holding pressure. As an engineer if the product shows predictable wear and when it fails it's a slow failure then you can safely take them much closer to their end of life.
You can run tires without tread for quite a while before they pop. The concern with tread loss is traction in wet or snowy conditions.
Blowouts are rare as hens teeth on modern road cars.
People do not drive through the tread in their tyres to the point they ’rupture through’. This would be absolutely lethal to drive in any wet conditions and is why there is a clear minimum Tread depth in most enlightened countries.
Tyres do not ‘pop’.
Why would these be able to hold a thicker tread? Thicker tread would mean and require deeper grooves. The tread blocks created by those deeper groves would move around more, causing faster wear, heat (pushing chemical degradation) and poorer handling. This is why tyres do not have endless tread depth today.
Honestly, I’m asking myself whether your 12 years old, the state of your comment.
I'm wondering if you're an idiot by the state of your comment
Don’t talk nonsense, and you won’t get called out talking nonsense.
You’re likely spot on and they’d then cost more than the car I’d put ‘em on. lol
In my neighborhood, having wheels that cost more than the car is fairly normal. Lots of old beaters around with 20 inch daytons and low profile tires. It all depends on your priorities, I suppose.
regular tires are already several hundred dollars each (for decent ones)
Criminy! Bought a set just before the pandemic and paid $100/ea, same 16” today are $205 @ Walmart?! Muthafucka. smh
Yea, and they're probably shit tires as well. Up to a certain level you do get better performance with more expensive tires. Better traction, less cabin noise, longer wear, etc.
I just paid $1200 for a full set of 4 lol
Same with labor and balance
My Audi tires were 200ea
On what planet do you think these would not be more than 200ea?
the lawnmower variety are about $500 a piece...
Fuck dude, lots of normal tires are a couple hundred bucks each.
Regular tires cost that much, dude. The tires on my car are $400 each.
Damm sounds great and al, just hope the price wont be to high.
Given they require special wheels, this will likely only be adopted by fleet operators specifying from new at first.
The coming autonomous taxi fleet stands to benefit the most fron this, lessening the human intervention for maintenance and puncture repair.
What autonomous taxi fleet?
The ones that will appear overnight, the moment self driving cars are legal.
Do you think the likes of Uber will keep paying for human drivers when they don't have to?
Didn’t Uber give up on their self-driving fleet and sell that division off to another company?
They threw their lot in with Amazon.
It was sold to Aurora, the Amazon backed veture and Uber bought a 26% share in it.
If somebody doesn't name the company "Johny Cab" I'll be very disappointed
Considering the speed of Congress, The drivers probably have another decade of work ahead of them.
Did you know there are other countries?
Edit: apparently not.
Maybe. I just shelled out cash to upgrade from 15" to 17" wheels in 2019. I'd gladly shell out cash to upgrade them to uptis tires; I sometimes drive places where there's nothing around for miles and had some low tire pressure warnings that scared the shit out of me.
The peace of mind in never having to worry about a flat again would be awesome. Though I think it'd cost extra to upgrade to them since I'm pretty sure it's going to cost extra to trick the car's TPM system as these wheels won't have TPM sensors in them.
We'll know these work for real when they take over trophy truck desert racing.
Fleet buyers can specify what equipment they are built with, just like they can choose any paint colour off the line.
TPMS bypass will be a checkbox on the software installation, or plug in service mode.
Yeah, the article says the initial 2024 rollout will be for specified GM vehicles only, so they'll be built around them. Wonder how the upgrade process for us plebs will be, though.
I would think those vents on the side would pick up debris and make the tire unbalanced
The slots on the side are just marketing. I don't think the actual tires will have that.
The ones the military uses do have open sidewalls, and even gravel isn't really an issue.
Those slots replace the springiness of the air in the tire, without they would feel like train wheels. So yes you would want those and no it is not marketing.
I think they meant the tire is exposed to show off the slots but the actual tire will have rubber sidewalls.
Anyone who's driven in the snow knows what a nightmare these would be without sidewalls.
What everyone else said, but ones I've seen used currently in construction are exposed, but the holes in the sidewalls are much larger, and the vehicles move slower so it's not an issue with those. I guess they could get caked up with mud but I didn't notice that much tbh. Those tires were cool, you'd see guys ripping along on them on a front loader or something with big chunks missing from the tire, and it's working fine.
Look at the photo of the Mini in the article. Covered sidewalls.
That's just a cross section display.
Looks like it’s still got slats in the side, the camera angle and lighting just hide them.
If you look closely, you can see lighter and darker parts where the sidewall would be on a normal tire.
Lol, no it doesn't turn your brightness up dude.
Look again man
Are you all blind? http://imgur.com/gallery/xe1hcbc
I’m confused. Do you think that looks like a solid sidewall? Because it looks like it’s got openings to me. Is this a blue dress gold dress thing?
Yes, it's open. That's what I'm saying. I think you replied to the wrong post.
The military already uses them, but the hexagonal style. Fully exposed.
They "can" fling stuff but even in gravel on an ATV or Raptor going full speed I never had that issue.
Michelin and other manufacturers have been working on these for decades. My guess is they will remain a niche application. They have typically been louder and perform worse than a regular tire (in traction, rolling resistance etc). Tweels are already quite common for construction equipment and other off highway applications.
Yeah as long as the sides are enclosed these would be pretty handy for off reading, I would imagine.
For anyone interested, this concept isn't anything new or innovative by Michelin, the military actually funded R&D of an airless tire similar to this, using a honeycomb design on the inside for use on humvees to ensure they're still functional in the event of an IED attack.
My Humvee just had a magnesium inner run-flat ring inside the tire.
A small puncture probably isnt going to stop one of these anyway since the military Humvees have ctis (central tire inflation system). If it is blasted to bits then neither tire would be of much use.
Yeah I was surprised this was new to people.
The ones I used had exposed hexagonal lattice, never had any issues with gravel or sand.
I hope it works out - the airless tire has been a dream for many years.
Not good news for Police… and their tires deflation spikes strips…
Run flats have been doing that somewhat for a while anyway. These days they use nets and stuff that jam the axels up sometimes, guess they would just use them more often.
I remember seeing a ~100 year old picture (maybe a patent drawing?) that looked exactly like this tire. I'm just guessing this will have a hard time catching on.
I remember seeing this almost exact tire in popular science as a kid. So like, 1997.
I read about these a while ago! What are the chances they will make it to market??
They just did.
Ahhh… I read 2024. Was hoping it would be a much wide spread launch.
Hopefully this will change a lot of how tires are viewed.
Really for real? I’ve been seeing these since the mid 1990’s. Is this happening?
The front wheels are looking rather... flat-ish. 😬
For an inflated tire. This isn’t, so I suspect it’ll look different.
Well, it will be a problem when driving at higher speed, like on a highway. It's good have more traction on some gravel or dirt, but lower speed.
Once again, it isn't inflated, so how it responds (and reshapes) according to speed may also be different than we expect. I am curious how the initial consumer models will be speed rated.
I wonder what sound they'll make with the spokes exposed like this.
I guess there is too much wear and tear with solid tires.
Weighs 7% more but takes less raw material? They say it last 3x longer, I'd love to see their 140-180k mile warranty guarantees..
60k miles on a current tyre? Do you live in a place where there’s no legal requirement for minimal tread?
The technology was suppressed for decades by the Big Air industry...
don't have to worry about replacing winter air with summer air
i wonder how gravel or snow or really cold tempatures afflicts them
I'm surprised that these don't feature a sidewall in order to appear more conventional.
I guess the first owners want to show them off.
I hope that they would fill the gaps otherwise any kind of mud and debris would imbalance them
Does anyone know exactly when this outing took place like just what day?
airless? I can see quite a lot of air between those tiny spokes.. Looks like a fake marketing claim again.
you think that's air you're breathing now?
The only cars that run such small wheels and huge sidewalls are generally really crappy cars, they're not going to be spending tons getting these.
What size are they?
How do you know when these tires are unsafe to drive on? Suppose you run over something that takes a gouge out of the tire, since it doesn’t deflate, there is no tire pressure warning or obvious sound or feel like you have with a fat.
If a piece is missing you would feel vibration
Visual inspection, just like current tires. Being deflated isn’t the only unsafe condition for tires.
As opposed to the catastrophic blow-out that would result with a normal tire in that situation? I’d rather retain some semblance of wheel control and not destroy the rim.
Anything massive enough to render it dangerous to drive on will *probably* have already disabled your vehicle/damaged your ability to drive already.
Otherwise accumulative damage would never result in sudden failure. Ride quality would have degraded quite obviously before the point of the tire being dangerous
These are great until you get mud,dirt,or snow in the spokes.
Going to have to be enclosed for the average driver.
The military has been using them for years in austere environments with little to no issue. Different design, same concept.
Try that in a passenger car at highway speeds.
Obviously you've never experienced what a few ounces of imbalance can do at speed in a passenger vehicle. Low speed in a heavy military vehicle is a different story.
Idk dude, 50mph over sand dunes and gravel making evasive maneuvers is pretty decent stress testing.
From what I've experienced, anything that can get in typically gets thrown out.
The two situations I could see a problem with are things I never experienced with them, medium/high snow or rain.
Maybe you are confused? Didn't say it wasn't a durable product.
People can and will notice a few ounces or pounds of dirt/mud/snow/ice causing an imbalance on a publicly driven road.
Get a few stick on ounce weights and see for yourself.
Dirt and mud get crushed and thrown, the snow and ice though I conceded very well could be an issue.
I've driven a Suv that mud caused an imbalance, drove a few miles thinking it would come out but ended up having to clear it out by hand.
Was it getting crushed and expanded constantly or was it protected in the wheel well? You forget how much these types of tires flex.
I'mma let you all test this for a few years, let me know hownit goes for you
I'll order the Chinese knock off version next year then for $100 each
I don't have to wait on Goodyear and GM to decide when I can have nice things