> I don't feel safe biking on the street, and would rather stay on the sidewalk like I did when I was a kid. I would just have to pause to check before crossing driveways and intersections.

This is a common misconception among folks who don't cycle. Cyclists are actually safer on the street. If you ride on the sidewalk, you have to deal with more potential issues such as pedestrians, driveways and intersections become even more dangerous because you're behaving as both a pedestrian and a vehicle with the all the disadvantages of both. In general, cyclists are the most unsafe where cars are not expecting them. Large suburban parking lots, for example, are particularly hazardous for cyclists-- experienced cyclists use extreme caution in parking lots, believe it or not.

Cycling is not particularly dangerous, depending on how you define "dangerous".

Most car-bike collisions occur at intersections and are "right-hooks". This is when a car turns right, cutting across the path of the the cyclist and the cyclist hits the car because there's not enough room to stop or turn. These accidents typically result in bruises, damage to bike and sometimes a broken collarbone. They're rarely fatal unless the right-turning vehicle is a truck and the cyclist ends up under the truck.

The accident you're probably thinking of is a car hitting a cyclist from behind with a huge difference in speed. This, I believe, results in the most fatalities for car-bike accidents. It is relatively rare.

    > ...what chance do you have from a physics standpoint to be truly safe...

None. You have no chance to be truly safe. That's an unrealistic goal for any kind of traffic system.

As I said, I am aware that you are supposedly in danger at driveways etc. I said I would pause to check at driveways and those places. You did not acknowledge or read what I wrote, you just took the opportunity to give me a patronizing lecture.

It is realistic to try to avoid putting myself in a position where I may avoid being hit or run over by a car with no steel or anything to protect me. And we are making massive strides in terms of safety with things like self-driving cars.

Sorry, don't mean to be patronizing.

You may know that risk can qualitatively be thought of as a product of two factors: the severity of the outcome and the probability of occurrence.

In the case of cycling a high-speed rear collision with a car is very unlikely but very severe in its outcome. How common is this accident? Not very common-- it ends up on the news when it does occur.

Many many cyclists enjoy riding, on the street, for their whole lives and never have a serious accident or injury.

I was a cyclist for many years and stayed to the sidewalk as much as possible. As you said , must fatalities occur when a car traveling at a high rate of speed rear ends a bicyclist. I'd rather deal with the non fatal accidents that happen on the sidewalk then potentially fatal accidents on the street.

People fly by you in their car, inches away, while on the street on a regular basis, and you have no control over this. On a sidewalk, I have to be more observant, but more accidents there will be avoidable if I am paying attention.

> This is a common misconception among folks who don't cycle. Cyclists are actually safer on the street.

Heard this a thousand times and I don't buy it for a second. The speed differential between cyclists and pedestrians is an order of magnitude different than the speed differential between cyclists and cars. And the argument about driveways and intersections falls 100% flat on it's face if you use the incredibly basic assumption that cyclists should (a) use crosswalks and (b) shoulder check when crossing driveways.

> The speed differential between cyclists and pedestrians is an order of magnitude different than the speed differential between cyclists and cars.

A pedestrian walks at around 3 to 4 mph. A cyclist can ride at 15 to 20 mph. Cars on suburban streets can go 25 to 40 mph. That's about a 12 to 16 mph difference between a pedestrian an a cyclist and a 5 to 25 mph difference between cyclists and cars.

Speed differential is not the whole story.

What is also important is the nature of the collision. A glancing (side-swipe) collision, is very different from a direct collision. Also in right-hooks, the most common collision of all, you have a cyclist colliding with a slowly turning car while typically braking and turning at the same time.

But even if we're talking about direct collisions, the cyclist often ends up going over the hood or roof of the car simply because of the height of the bike vs the car. This looks awful but is actually better than hard impact.

There are more factors than mass and speed differences.

> I believe that there will eventually be something like a smart safe city where 2000+ pounds vehicles to not freely mix with pedestrians, cyclists, and baby strollers.

I think it's called Amsterdam ;-) More seriously, I went there recently and it's amazing how natural cycling is, everyone uses a bike, there are trams, and cars are clearly second-rate citizens in most of the city. An additional side effect of that is that everyone seems to be fit and healthy…

Unfortunately the cycle lanes in Amsterdam are also used by scooters which often illegally go much faster than bikes and emit more carbon monoxide than cars.

There's a bizarre exception for two-stroke engines in our emission regulations. I don't understand why. Electric scooters and e-bikes are a perfectly valid alternative, if clean 2-stroke engines aren't possible.

They will likely be pushed off the lanes within a couple years.

Yes they are very smelly

True. Also, cities just seem to drop bicycle lanes on the sides of streets without thinking about how the traffic would flow. Right-hand turns are a particular issue - I've seen lanes where the care lane is on the left and the bike lane is on the right, then to accommodate cars make right-hand turns the two lanes suddenly switch (bikes are supposed to cross over to the left while cars are supposed to cross over to the right). In situations where there isn't a right-hand turn lane, I've been told that the car is supposed to merge into the bike lane and drive along it and then make the turn from there (so that it doesn't try to suddenly drive into the lane when it reaches the intersection).

I'm sure there are ways these kinds of things could be handled well (maybe lights that separate the two forms of traffic?). But it seems like a lot of places are putting these in without much thought, and with the assumption that there won't be many cyclists - because if there were, some of these intersections would become dangerous messes.

What point are you trying to make? Obviously cars have safety features for people inside them. Are you arguing for safety features on cars for the people outside of cars, or safety features on bikes to combat cars?

All I read from your post is that cars are big and heavy, which would hurt unprotected people. In some cities people bike less. Ft worth is way too hot to bike, and definitely not average for bike culture.

One safety feature that cars could have for bicycles is Wide-angle rear-view mirrors[1] by default. I put one on my car when I lived in Austin to soothe my anxiety that I would kill someone and it did wonders for my situational awareness.

https://www.amazon.com/Fit-System-RM011-Clip-Mirror/dp/B001A...

The point is that one of the main reasons that there aren't more people biking may be that people feel unsafe because of the physics and that one way to see that is to compare the standard of what is safe for people riding in cars to what is safe for people riding on bicycles.

Would you buy a car if it received less than average safety scores? But all of the cars with those below average safety scores have large metal frames, a body, and a huge amount of mass that as I said, due to the basic physics equations means that the occupants of a car will be much, much less likely to be injured or killed if there is a collision. So considering how seriously people take car safety regulations, this is a bit of a crazy double standard.

But cycling isn't unsafe. Cycling is only unsafe in the proximity of two ton vehicles and their incapable operators.

It continues to be unsafe in this manner because we treat cars and trucks different to all other transportation. It's unthinkable we all shrug our shoulders when a pilot crashes a plane because he was checking his Facebook. There is a root cause analysis and there are effective measures taken. But here we are with car casualties many times that of planes or trains and yet no one is doing any cause analysis at all. Car manufacturers continue to produce ridiculously overpowered and oversized vehicles and advertise them speeding through the city at night.

Right but we are required to be in close proximity now. Let's build some smarter, safer cities where we aren't required to be close and maybe have physical barriers. It's just basic physics equations that aren't adding up to any type of real safety for me with current designs.

Cycling can be unsafe, with or without the proximity of heavy vehicles.

Just the other day I came about a cyclist driving on the shoulder, against the flow of 80 km/h traffic, with his hands off the handlebar. Insanely dangerous no matter how capable the drivers of the cars were. (Not to mention it's not a good idea to think you could safely check you Facebook updates as long as you were, say, cycling, or even walking about.)

Safe to say cyclist are one zealous bunch of they hobby, at least on every article related here on HN.

As I understand it, the safety scores for a particular car are relative to that type of car, e.g., compact, mid sized, etc.

So I expect a tiny little subcompact hatchback to be less safe than the average car overall. Yet it's what I drive.

Also, based on what I've read about statistics, I expect driving a car to be less safe than riding a bus, yet I drive a car.

Still, I suspect you're right that a lot of people are afraid to ride a bike. When folks see me pushing my bike out of my workplace, they get a look on their face like I'm about to go skydiving without a parachute, and say: "Pleeeaase be careful out there."