why are different sized tires pressurized so differently? for example my bikes tires are supposed to be inflated at 55 PSI but my mom’s car is supposed to be inflated to 25 PSI? and I don’t think it’s tire size because our side by sides are also 25PSI

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why are different sized tires pressurized so differently? for example my bikes tires are supposed to be inflated at 55 PSI but my mom’s car is supposed to be inflated to 25 PSI? and I don’t think it’s tire size because our side by sides are also 25PSI

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Anonymous 0 Comments

Its about the tire contact area

The total contact area of the tires times the pressure inside the tires will equal the weight of the vehicle

Your bike tires have a very small contact patch to give lower rolling resistance(more tire touching means more squishing which means more energy lost) so it needs high pressure to support the weight in that small area

The car tire has a much larger contact area. Four tires each with a 5″ by 5″ patch will support a total of 2500 pounds. A lot of car tires are higher pressure, a 5×5 patch on 4 tires at 35 PSI will support the full weight of a 3500 pound car

You’ll notice that for cars with a “donut” spare, the spare tire is much narrower and gets inflated to a higher pressure. This is because the narrow tire has a smaller contact patch and needs the higher pressure to support the same weight.