• CookieOfFortune@lemmy.world
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            1 month ago

            Yes fuel economy. Energy expended per distance traveled or power needed to maintain a given speed. Just the fuel in this case is burned by your own body.

            At world class levels, a few watts here and there will make a big difference by the end of a race.

            • Arcka@midwest.social
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              1 month ago

              Aah, gotcha. I had thought that

              Probably less these days

              was in reference to this part at the end of the parent comment:

              cars generally float around the 32 psi area

              and I haven’t seen anything to contradict all the previous literature on under-inflated automobile tires being worse for fuel economy.

              • CookieOfFortune@lemmy.world
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                1 month ago

                Yeah it’s because the theory has been that high pressure decreases tire deformation and this is more efficient. This is where the wisdom of under inflated tires become less efficient. However lower pressure (like 80-90 psi) allows bicycle tires to absorb road imperfections and vibrations which actually ends up slightly more efficient. But if you go too low efficiency will be negatively affected.

                Airplane tires actually have very high pressures to prevent hydroplaning, which is more important than ride quality or fuel efficiency for them.

                • Blaster M@lemmy.world
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                  1 month ago

                  Also planes have to land, and the impact on the tires is like hitting a pothole. You don’t want the tires to touch rim at ~200 MPH on a many-million-dollar vehicle

        • Tja@programming.dev
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          1 month ago

          Source?

          All the studies I’ve read (and my experience) show that narrower tires and higher pressures improve economy. Less traction and less ride comfort are the tradeoffs, respectively.

        • _thebrain_@sh.itjust.works
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          1 month ago

          In not really talking about possible, I am more talking real world running pressure.

          I’m sure you can air up a car tire but at 90 psi it would be so rock hard that travel on it would be extremely uncomfortable. Also you would risk blowing it out whenever you went over a big enough bump. The tire volume inside would deform and cause a massive pressure spike.

          Tractor trailer tires are made with more layers of rubber and steel belting so they can safely handle higher pressures.

          • jcs@lemmy.world
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            1 month ago

            Right, you would likely pop a tire on your friendly neighborhood pothole. Even if you were lucky and avoided all of that, the tires will bulge in the center, drastically reducing the contact patch with the ground and you’d have probably 15-35% traction compared to proper inflation.

        • errer@lemmy.world
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          1 month ago

          Yeah you can definitely do it with car tires for a short time at least, that’s how you check for leaks (overpressure to like 80 psi and put it in a tub of water, look for the bubbles)

          • Rhaedas@fedia.io
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            1 month ago

            You do not need to overpressurize to find leaks. This is dangerous advice, as a tire blowing at even lower pressures can kill you. And there won’t be any warning before it does.

            • errer@lemmy.world
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              1 month ago

              Sorry buddy but you’re full of shit, this is standard practice at tire shops. The reason you overpressure is that a tire at rest may not lose air noticeably, you overpressure to mimic driving down the highway when the tire is bulging out more due to centrifugal forces.

              80 psi for a few minutes is not really that dangerous, the tires blow up at 120+ psi.

              • Rhaedas@fedia.io
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                1 month ago

                I won’t be as rude, but you are the one making a claim that exceeds both common sense and the warning on a typical car tire sidewall. A leak from a puncture area, bad bead seal, or tire failure point will show at normal inflation pressures with a water/soap test, as anyone in their backyard can attest to. You don’t need to simulate flexing and stress for this, in fact pushing the tire to its limits with high pressure will absolutely find a failure of the tire structure very quickly, which was the point of my warning. Maybe you’ve never seen or heard a tire explode. It doesn’t pop like a balloon.

                I would question any shop doing this procedure from a manufacturer’s recommendations and from OSHA standards.