I witnessed a bike crash just last week (in Boston) where the convoy was biking (around ~30 kph I think) and some asshole opened his car's door without looking his surroundings, and the biker in the front bumped into the door and flew over her car. Luckily, the road was clear (so she wasn't crushed by a car) and she had a helmet. She was fine but she had a concussion. Clearly, if we were going at 25, the likelihood of she dying would be even lower, and if we were going 50, it would be significantly higher (her bike could break door's glass and she could have permanently injured herself).
I don't understand this whole thread. If you're biking in a city like Boston or SF early in the morning or around 5pm, you're trying to go office/home. What's the point of biking at 50 kph? This is not recreation. This is something I do every day and my highest priority is doing this as safe as possible. Similarly, would you drive significantly faster than speed limit with your car, because you arbitrarily think "it's not dangerous"? It's nice that you think bumping into things at 30/50 is not dangerous, I respectfully disagree and consider it absolutely dangerous and kindly invite you to stick to whatever speed limit you have in your city. People are just trying to get to their work or kids and be done with their days, please don't try to be Superman.
Where are you getting 50kph from? Nowhere did I suggest that was a safe speed for daily riding.
We've been talking about 35kph, or 20 miles an hour, which is a perfectly reasonable speed for a bicycle. You're unlikely to be seriously injured if you crash at 35kph. People regularly ride 35kph throughout parts of their ride. It's normal, common, and entirely legal.
Your comments about "sticking to the speed limit" make no sense whatsoever. We're talking about speeds far, far below the speed limit even on residential roads.
I'm flabbergasted that you're having such a freakout over a bicycle going 20mph. I'd hate to see your reaction to an actual gas powered motorcycle or scooter.
I don't understand this whole thread. If you're biking in a city like Boston or SF early in the morning or around 5pm, you're trying to go office/home. What's the point of biking at 50 kph? This is not recreation. This is something I do every day and my highest priority is doing this as safe as possible. Similarly, would you drive significantly faster than speed limit with your car, because you arbitrarily think "it's not dangerous"? It's nice that you think bumping into things at 30/50 is not dangerous, I respectfully disagree and consider it absolutely dangerous and kindly invite you to stick to whatever speed limit you have in your city. People are just trying to get to their work or kids and be done with their days, please don't try to be Superman.