• Boddhisatva@lemmy.world
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    2 days ago

    Born from that research was a widely accepted concept known as the 85% rule, which suggests a road’s posted speed should be tied to the 15th-fastest vehicle out of every 100 traveling it in free-flowing traffic, rounded to the nearest 5 mph increment.

    Yikes. If they used this in northern Illinois, the speed limit on I90 West would be 85 or 90mph.

    • Frezik@lemmy.blahaj.zone
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      2 days ago

      On an interstate (all on/off ramps, no intersections, clear of pedestrians), that would be fine in terms of safety. The road would take more wear and tear, and gas millage plummets. At a certain point, the curves in the road don’t sweep gradually enough for all types of cars and trucks to handle it. If designed for it, 150mph can be done safely. The German Autobahn proves it.

      When you have intersections and pedestrians and such, things are different.

    • Cosmonauticus@lemmy.world
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      2 days ago

      Northern Midwest driving is in an entire realm of its own. I remember in Michigan i was on I94 and cop was flashing their high beams at me because I was going too slow in the left lane.

      I was going 90