And - the so called "friction" shocks are still available.
https://en.wikipedia.org/wiki/Fricti...shock_absorber
https://www.speedwaymotors.com/Speed...ocks,3799.html
Still in some use among the hot-rod crowd. One can actually "tune" these quite well to get to the "vibration neutral point."
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Critical damping is the "sweet spot" (Minimal time to restoration of neutral)
Putting your girlfriend in the passenger seat can screw this up.
That might be where the term "Hop-Rod" came from.
Joe K