3 ms·

There's a pretty big difference between going 20 mph vs going 60 or whatever on a motorcycle.

chemeng 5y ago
Definitely. Though I feel that many people may not know that the probability of a fatality in cyclist/pedestrian accidents increases dramatically between 20-30mph, and I certainly see a lot of ebikers doing 25mph+ in crowded areas that would be 12-15mph if not assisted.
jonpurdy 5y ago
Also, the stats for cars show that speed increases cause deaths to go up non-linearly, so your chances of dying in an accident are way more than double at 100 vs 50 km/h. I would assume the same about motorcycles and ebikes, but presumably the threshold would be lower due to lack of protection (motorcycle helmet and armour not as safe as a metal shell with airbags). So I wonder where that curve starts to rise up on bicycles and ebikes considering they wear just a bicycle helmet and no armoured clothing usually. (I loved riding ebikes in China (Kunshan) with wide protected lanes that were totally separate from traffic outside of city center (where speeds were low and congestion high, negating they need)).
dahart 5y ago
True, but I still don’t want to hit something going 20 on a bike. There’s a pretty big difference between going 10 and going 20 too. Physics lets us know that 2x the speed of a mass carries 4x the energy, so a 20mph crash does 4x the damage of a 10mph crash. I’ve had a bike crash into rocks at under 20mph that could have killed me were it not for a helmet and padding. (I did not walk away unscathed, years later I can still feel the injury to my shoulder…) Crashing at 60 on a motorcycle is pretty likely to kill you. Crashing going 20 on a bike might break bones - as long as you hit something stationary, rather than throw yourself in front of a car doing 40. Crashing at 10 mph and you might be able to jump off or walk away with only scratches. It’s also fun to think about how crashing at 1000 mph is not that much more likely to kill you than crashing at 60 mph on a motorcycle. At some point, the speed is enough to do all of the damage.

Definitely. Though I feel that many people may not know that the probability of a fatality in cyclist/pedestrian accidents increases dramatically between 20-30mph, and I certainly see a lot of ebikers doing 25mph+ in crowded areas that would be 12-15mph if not assisted.

jonpurdy 5y ago

Also, the stats for cars show that speed increases cause deaths to go up non-linearly, so your chances of dying in an accident are way more than double at 100 vs 50 km/h. I would assume the same about motorcycles and ebikes, but presumably the threshold would be lower due to lack of protection (motorcycle helmet and armour not as safe as a metal shell with airbags). So I wonder where that curve starts to rise up on bicycles and ebikes considering they wear just a bicycle helmet and no armoured clothing usually. (I loved riding ebikes in China (Kunshan) with wide protected lanes that were totally separate from traffic outside of city center (where speeds were low and congestion high, negating they need)).

dahart 5y ago

True, but I still don’t want to hit something going 20 on a bike. There’s a pretty big difference between going 10 and going 20 too. Physics lets us know that 2x the speed of a mass carries 4x the energy, so a 20mph crash does 4x the damage of a 10mph crash. I’ve had a bike crash into rocks at under 20mph that could have killed me were it not for a helmet and padding. (I did not walk away unscathed, years later I can still feel the injury to my shoulder…) Crashing at 60 on a motorcycle is pretty likely to kill you. Crashing going 20 on a bike might break bones - as long as you hit something stationary, rather than throw yourself in front of a car doing 40. Crashing at 10 mph and you might be able to jump off or walk away with only scratches. It’s also fun to think about how crashing at 1000 mph is not that much more likely to kill you than crashing at 60 mph on a motorcycle. At some point, the speed is enough to do all of the damage.