alt Hacker NewsI've never understood speed bumps as a concept. Almost every car has at least 4in of travel, so you can hit them at significant speed and not damage anything. In fact the faster you hit them or the more load you're carrying the better the suspension handles it because you open up the high speed compression valves. If there's no one around and it's an empty remote rural access road I'll often hit them at 30mph+ with no issue. Rolling over them at a slower speed where your shocks stay uncompressed forces your whole car to go up and then down again, instead of absorbing the energy in the shocks.
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>I've never understood speed bumps as a concept. Almost every car has at least 4in of travel, so you can hit them at significant speed and not damage anything.
They only work because the average consumer doesn't know this.
Properly built speed bumps are most comfortable to traverse at posted speed, but are very well felt when you're speeding. In my experience they build them well in Northern Europe, less so in Eastern.
> so you can hit them at significant speed and not damage anything.
That’s the point. They’re not supposed to damage the car. They’re supposed to be a little uncomfortable if you’re going too fast.
It’s more reminder than a physical stopper.
> In fact the faster you hit them or the more load you're carrying the better the suspension handles it because you open up the high speed compression valves.
This is a case of knowing just enough about a topic to be dangerous.
Entering the higher shaft velocity part of the damper curve doesn’t mean the suspension is handling it “better”. The high speed behavior of the valving simply means the damping forces aren’t increasing linearly with shaft velocity. They trade extra travel for reduced peak forces.
Make no mistake, though. The faster you go, the higher the forces. The high speed valving (if the OEM dampers are even digressive) isn’t changing that.
If the speed bump is tall enough and the bump stops get completely compressed you could bottom out the damper, which is not good for it.
> I'll often hit them at 30mph+ with no issue.
Just because nothing immediately breaks doesn’t mean you’re reducing the life of the OEM dampers. Repeated high speed impacts and will shorten the life. Getting the wheels bumped up into the range where you’re compressed bump stops transfers a lot of energy into the bushings and other components.
> Rolling over them at a slower speed where your shocks stay uncompressed forces your whole car to go up and then down again, instead of absorbing the energy in the shocks.
That’s the ideal way to do it. This is better than the sudden sharp impact of high speed crossing. You’re not doing your car any favors by driving quickly over speed bumps. Fortunately for you, OEM replacement dampers aren’t too expensive but replacing prematurely worn bushings is kind of a pain.