Bike crash energy… Let’s go fast!

Early 1900’s an [Olympic 440](https://academic-accelerator.com/encyclopedia/440-yard-dash) was 50sec.. so an average of \~18mph but that’s at naked weight…and let’s get serious, if you wanted to run a quarter mile at 18mph… few on the planet are in that kind of shape even today.

so still, let’s be reaching for the stars and say you could knock on a 5min mile… running at 10mph.

news flash… you probably can’t, but lets keep reaching as you start thinking about running your fastest right into a wall… how’s that gonna feel.

Lets to 200# with bike, the % won’t care about weights as much as speeds (yeah pounds because America FK yeah! and % DGAF about units)

And say the bike only takes up 30# making the rider a nice 170#

If you don’t like the weights in this fiction story, [work it yourself](https://www.calculatorsoup.com/calculators/physics/kinetic.php)

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anyway… an ebike prolly weights more and so do you. but stay calm, for sake of argument the % doesn’t really change for any consistent weights.

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so, solo runner @ 170#

bike @ 30#

rider with bike @ 200#

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|speed|KE in Joules|% +5mph|% over 15mph|% over 20mph|
|:-|:-|:-|:-|:-|
|run@10|770|\-|\-|\-|
|15mph|2,040|165% –>10mph|\-|\-|
|20mph|3,626|78%|78% (yeah maths)|\-|
|25mph|5,665|56%|178%|56%|
|30mph|8,158|44%|300%|125%|
|35mph|11,104|36%|444%|196%|

yeah the energy you’ll be asked to dissipate somehow rises that fast.

*KE*=1/2 (*mv*^(2)) that square will eat you.

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Now since Ukraine and IDK how many other conflicts are in the news let alone nightly news in every market here… let’s go big for reference, a [.45 Colt +P](https://www.americanrifleman.org/content/the-misunderstood-45-colt-p/) at maximum… mmmm maybe 1,600 J

You don’t ever want to face that, it’s silly.

And if you’ve never worked it… know this as fact, slow bullets that impart all their energy to the target (like a bike crash) is by far more lethal than a faster bullet that passes through a body. Why the hollow point bullets that mushrooms, can be more deadly. Yeah, impact… bullets don’t kill like that… fair.

Lets deal… strap a level III vest on and run your 10mph butt out to 600yds, I’ll wait while you are spent like riding a bike. Now bracket a NATO sniper round at \~1,300J right there.

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What you put your shape in at taking one round to the vest, let alone 3 for a 20mph crash, or 6 for a 30mph, or over 8 for 35mph crash? Keep in mind, even at a full run, you don’t have the KE of one the bullet to stop, now hit a wall… ouch.

Best of luck trying to walk it off. Remember, in a crash… all those hit at the same time and not in a vest… pick a limb or your head..

Be careful and wear your gear… Helmet with chin guard is nice, but MIPS tech is smart regardless.

by BWWFC