Comments by "kazedcat" (@kazedcat) on "I Tried Solid Bike Tires | Here's What I Found" video.

@Mallchad Gasses don't have deformation. They fit to the form of their container. What they have is pressure, temperature, and density. Solids do have form and rigidity so you need the foam rubber's rigidity to be as close to zero as possible so that almost all of the bicycles weight is supported by the trap air. Small cells of rubber containing trap gasses has a lot of options to make this happen. Major option is the shape of the cell. You want disk like cell with the flat profile along the direction of the pressure gradient this makes it so that the rubbers rigity is focus perpendicular to the pressure gradient giving a cosine factor approaching zero. Then you can adjust the gas density to make sure it is taking most of the load instead of the rubber. The hard part is mass producing the rubber cell with the correct shape and containing a gas with correct density. It is a manufacturing problem not a design problem.
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There should be no difference between lots of small pockets of air and a single pocket of air. Pressure will distribute into the entire mass without gradient.
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@Mallchad The internal part don't need to be tough. You just need the external rubber tire to contain the internal rubber foam and protects the internal part from damage. The leaking part is the same problem as pneumatic tires only it happens at a much slower rate due to having multiple tiny air pockets instead of one big air pocket.
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That is horrible. You want it to be no gradient so that it acts like a pneumatic tire. Pressure spreading evenly. Having a gradient means impacts will not transfer across the whole tire and instead stress will be uneven making you feel more of the bumps.
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@HenryLoenwind There is gradient otherwise you can use air pressure for faster than light communication. Yes pressure at equilibrium is constant but bicycle in motion is not in equilibrium it is in a dynamic environment. When you hit a bump the pressure near road contact is higher compared to the pressure on the opposite side of the wheel. This dynamic pressure changes is where most energy is lost due to the compressed air heating up. With rubber foam the rubber interfere with this dynamic pressure changes and energy is lost due to internal friction of the rubber stretching. You need to minimize this internal friction that is why you need the shape of the rubber cell that minimizes stretching along the direction of the pressure gradient.
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@HenryLoenwind No most energy loss in a bike tire is compression. There is no significant airflow within the tire because of the small cross sectional area. Almost all of the air will be force outwards towards the rubber tire because of the rotational motion and there is no shear force that can power a counter flow.
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@tvuser9529 Then have a regular tire filled with foam.
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