I'm unimpressed with their pilot location choice. Las Vegas?
Chicago or NYC would be much more of a proper test with potholes, humidity, potholes, temperature, potholes, and precipitation. Did I mention potholes.
Michelin Airless
141–150 of 316 posts
Re: Michelin Airless
#142the michelin man is so full of air though
Re: Michelin Airless
#143Re: Michelin Airless
#144"Every year, 20%* of tires are discarded as scrap " Really? They cite a survey, but don't link to it.
Tires are usually rated for 40 ,000 to 60,000 miles. Americans drive 13,500 miles per on average[1]. That would cause tires to be replaced on average after ~4 years. So yeah, seems believable. [1] https://www.fhwa.dot.gov/ohim/onh00/bar8.htm
I have never gotten the rated tread lifetime on a tire. I've gone through maybe 60 tires in my lifetime and none of them were replaced due to punctures (I had one repairable puncture). Partly because 90% of my miles are stop/go rather than cruising.
Re: Michelin Airless
#145Former automotive engineer chiming in. "Tweels" have been around a long time, but have always failed in terms of "NVH" (noise, vibration, harshness). Michelin is claiming that this generation of tweels are appropriate for passenger cars, which means that they think they've solved the NVH problem. They seem to be marketing these alongside EVs, I wonder if they're only really intended for lighter, compact-style cars. (…
Does the focus on NVH imply that the increase of rolling friction over time is negligible compared to the tread lifetime ? Or is that partly of the reason to target lighter vehicles. The above assumes the spokes(?) become stretched over time it would increase displacement of the center of rotation from the center of mass which if recall is what creates rolling friction.
The marketing focuses heavily on reduction in disposed tires as the environmental benefit. If the tire were equal in terms of rolling resistance we'd see them at least mentioning it in the graphics.
Re: Michelin Airless
#146Earlier quoted context omitted.
A lot of heavy equipment drives around with water-filled tires, so it's already there. Definitely not what you meant though.
Hmm, why water filled? I can't think of any advantages, but can think of downsides such as a massive increase in unsprung weight.
The only time they move fast enough to worry about unspung weight is when they are on a trailer.
That isn't strictly true, but in general such equipment spends most of it time moving very slowly it it moves at all. Transports speeds do become a problem, but that is only done for a short time (or you have it on a trailer so you can go faster) so nobody worries about the issue.
Re: Michelin Airless
#147"Every year, 20%* of tires are discarded as scrap " Really? They cite a survey, but don't link to it.
You misunderstood; the claim is that 20% of the tires that are discarded are due to punctures or improper inflation.
12% of the tires that are discarded are discarded due to punctures or blowouts and 8% of tires that are discarded are discarded due to uneven wear caused by improper inflation.
Re: Michelin Airless
#148The magic of the pneumatic (air-filled) tire is that the entire air-filled space of the tire acts to absorb shock and vibration from the road surface. Airless tires give up this advantage, and only the tire structure between the wheel and contact patch are available to do the same work. The result is always a heavier tire that is a harsher ride. All the materials science in the world can't and won't find a solution t…
The result is also always an efficiency loss. Periodically solid bike tires become faddish and it's like pedaling a bike made of lead.
Re: Michelin Airless
#149Earlier quoted context omitted.
EVs are quite heavy for their footprint due to the weight of the batteries.
There are exceptions though like the upcoming Aptera which only weighs around 800 kg even with a large range.
Unfortunately, they are also making a lot of claims that they haven't demonstrated in a working vehicle yet. Getting to production is going to be hard.
Re: Michelin Airless
#150Earlier quoted context omitted.
I picked a gas car of comparable size. The Civic and Golf are much smaller than the Model 3.
The Civic is 2 inches shorter and 2 inches narrower than the Model 3, but it actually has a larger interior volume by one cubic foot. Size up to the Accord which is 8 inches longer and a half inch wider than a Model 3 (and 9ft^3 more interior space), and it still only weighs 3131-3362 lbs.
The 3 has at least 5 cubic feet more in cargo space than the Civic. In practice there is a pretty big difference between those two cars.