A Type of Road Junction that Kills Cyclists • Hacker News Board

Re: A Type of Road Junction that Kills Cyclists

#321

Post by lmm » Wed, Jan 10, 2018, 1:12 PM UTC

michaelt wrote: post #305

lmm wrote: post #278

Earlier quoted context omitted.

Let's be careful not to conflate two things: conforming to red lights isn't a goal in itself, safety is the goal. A lot of drivers get exercised about "cyclists running red lights" in cases that are actually safer than the alternatives, e.g. cyclists crossing a junction ahead of motor traffic when the junction doesn't have a dedicated light phase for cyclists. Cyclists running up the inside mostly happens because wai…

waiting in a queue of traffic at a light or junction is very dangerous for a cyclist When I'm approaching traffic lights and there's a queue of traffic and no bike box, I stop my bike at the tail of the queue, in the middle of the lane - just like I would on my motorbike or in my car. I'm curious as to what you think the danger is in that situation?

A driver coming up behind you as you're starting to set off ( or immediately after you've fallen down) when the queue ahead of you is already moving. Somehow you tend to blend into the queue visually - the driver doesn't see you as separate from the vehicle in front of you, and doesn't realise you're still there when the vehicle starts moving (or does realise you're there, but rushes past you unsafely) - and the risk of falling over is much higher as you're starting off than at any other point.

Re: A Type of Road Junction that Kills Cyclists

#322

Post by usrusr » Wed, Jan 10, 2018, 1:13 PM UTC

bambax wrote: post #172

ajmurmann wrote: post #65

Earlier quoted context omitted.

A roundabout is a much better solution than a stop sign. I still believe that the ubiquous stop signs in the US are there due to the oil lobby. Bringing a car to a full stop is incredibly wasteful.

A roundabout is always the best solution, but it's very expensive. Replacing the "Give Way" by a stop sign costs almost nothing and would probably help a lot, although not for truly reckless drivers.

Traffic lights chop up traffic flow, creating windows of opportunity for turns and crossings at minor intersections downstream. Roundabouts on the other hand create bottlenecks of relatively constant throughput, smoothing out any pulsation in traffic density (e.g. from upstream traffic lights), which makes minor downstream intersections much more difficult.

Determining the best option for a given case is more an at than a matter of simple preferences.

Re: A Type of Road Junction that Kills Cyclists

#323

Post by astura » Wed, Jan 10, 2018, 1:13 PM UTC

giardini wrote: post #37

A few speed bumps at the intersection would slow drivers. Speed bumps are cheap and effective. You can lay several in series to encourage drivers to slow. It would be a shame not to use them in such an instance, where lives might be saved.

Don't speed bumps make plowing difficult?

Re: A Type of Road Junction that Kills Cyclists

#324

Post by u801e » Wed, Jan 10, 2018, 1:15 PM UTC

swimfar wrote: post #54

u801e wrote: post #36

Earlier quoted context omitted.

The US also tends to overuse stop signs when a yield (give way) sign would suffice. That is, if there is sufficient visibility of approaching traffic, coming to a complete stop is not necessary to safely yield to any conflicting traffic. Also, coming to a complete stop and then proceeding isn't sufficient to properly yield to approaching traffic. In the end, stop signs end up being treated like yield signs. The only…

In the end, stop signs end up being treated like yield signs. This definitely varies based on where in the US you are. In California almost no one comes to a complete stop. (That's probably why rolling through a stop sign is called a "California Roll"). But in many other parts of the country people do, even if there are no cars around.

In my experience driving through many states in the eastern part of the US, it's not really any different compared to your description of how drivers in California deal with stop signs.

Re: A Type of Road Junction that Kills Cyclists

#325

Post by dsego » Wed, Jan 10, 2018, 1:16 PM UTC

alkonaut wrote: post #313

dsego wrote: post #308

Earlier quoted context omitted.

Imagine driving towards an intersection. There is no sign telling you if you have priority or not. There is a red car coming from the right. Then you notice that the red car has a stop sign in front of him (you recognize the shape). You infer that you are on the main road and you can ignore the right-hand rule.

Sorry, I understood what you meant, just not what the relevance was. What you are saying applies, and applies universally (regardless of whether there also exists multi-way-stops).

That there is no need for supplemental signs I guess.

Re: A Type of Road Junction that Kills Cyclists

#326

Post by usrusr » Wed, Jan 10, 2018, 1:18 PM UTC

wizzard wrote: post #120

ajmurmann wrote: post #65

Earlier quoted context omitted.

A roundabout is a much better solution than a stop sign. I still believe that the ubiquous stop signs in the US are there due to the oil lobby. Bringing a car to a full stop is incredibly wasteful.

I have roundabouts in my neighborhood. They have the exact same problem. If you don't come to a full stop and/or look around your A pillar deliberately, you may never see the car or bike hidden behind it. I've also had the same problem turning onto a crossroad without coming to a complete stop at the stop sign first. I believe the only real solution is driver training.

But you modulate speed and rotate the car while navigating the roundabout, which solves the constant speed/constant bearing problem. At a roundabout, blind spots are all over the place and will never perfectly track another traffic participant.

Re: A Type of Road Junction that Kills Cyclists

#327

Post by talldan » Wed, Jan 10, 2018, 1:18 PM UTC

u801e wrote: post #274

talldan wrote: post #240

Earlier quoted context omitted.

The highway code says that cyclists should stay to the left. Even on a roundabout with multiple lanes, cyclists are supposed to stay to the left and cycle across exits. I don't ever follow that rule when cycling, it does seem dangerous, but it is the rule, regardless of whether you disagree. You should always check blind spots when turning left, and you should have been coached to do this when learning to drive.

> The highway code says that cyclists should stay to the left. The uniform vehicle code (which is the basis of many state road rules in the US) states the following: >> Any person operating a bicycle... shall ride as close as practicable to the right-hand curb or edge of the roadway except under any of the following situations >> [...] >> When reasonably necessary to avoid conditions including [...] substandard width…

I completely agree. There are similar rules over here about leaving a gap to the kerb, and that there should also be a gap left by overtaking vehicles. Both are often not observed.

Here's the (brief) rules for roundabouts: http://www.highwaycodeuk.co.uk/rules-for-cyclists-roundabout...

Most cycling proficiency courses here in the UK will tell cyclists to ride more centrally when in a narrow lane, which is good advice. A cyclist is also legally allowed to do that.

It gets a bit fuzzy though when there's a cycle lane provided.

Re: A Type of Road Junction that Kills Cyclists

#328

Post by ptaipale » Wed, Jan 10, 2018, 1:21 PM UTC

Xylakant wrote: post #319

papermule wrote: post #238

Earlier quoted context omitted.

Why shouldn’t cyclists need a license to ride on the road? Others road users must have one. ---- It's a shame I'm getting downvoted, but the current state of affairs is that in cities like London bicycles, cars and trucks will be sharing the road for the near-mid future. I'd rather not have trucks or cars in the city, and ideally cyclists would have their own road separate from cars and pedestrians, but I think that'…

> Until then what else can do we? At least if we require tests for cyclists, like we do for cars, buses and trucks, it might help reduce the number of cyclists doing risky things that perhaps they aren't even aware of? Statistics show that in the large majority of cases of accidents between cycles and motor vehicles, the driver of the motor vehicle is at fault. Requiring a license for cycles will do just about nothin…

>Statistics show that in the large majority of cases of accidents between cycles and motor vehicles, the driver of the motor vehicle is at fault. Requiring a license for cycles will do just about nothing to fix this.

As a regular cyclist, I would say that requiring a license from cyclists would certainly do something to fix this: make cyclists more aware of it.

Over here, about 2/3 of collisions between motor vehicle and bicycle are fault of the motor vehicle driver. But that leaves 1/3 where cyclist errors or breaches of traffic code are reason, which is also significant.

And then there are actually quite many cyclist accidents that do not involve a motor vehicle.

Re: A Type of Road Junction that Kills Cyclists

#329

Post by usrusr » Wed, Jan 10, 2018, 1:24 PM UTC

bdamm wrote: post #17

temp-dude-87844 wrote: post #8

There's a lot of math in this article about blind spots and car pillars and whatnot, but a Google Maps Street View appears to show the terrain and brush blocking the view on approach [1][2], making all of this math largely moot. That the drivers in question didn't even so much as slow down for this approach is beyond reckless, aside from the other lawbreaking that followed. The 'Give Way' sign is idiotic, put a Stop…

Indeed, a stop sign would solve this, wouldn’t it? Simplist & cheapest solution first. The point about the geometry is that it doesn’t matter at which point the driver can see over the hill and brush; they still won’t see the cyclist.

When the sight lines are blocked, the false sense of safety which is undermined by theconstant speed/constant bearing blind spot simply would not happen. If you don't think that you know that the other road is empty (because you can't see it), a yield sign is enough.

Re: A Type of Road Junction that Kills Cyclists

#330

Post by alkonaut » Wed, Jan 10, 2018, 1:25 PM UTC

dsego wrote: post #325

alkonaut wrote: post #313

Earlier quoted context omitted.

Sorry, I understood what you meant, just not what the relevance was. What you are saying applies, and applies universally (regardless of whether there also exists multi-way-stops).

That there is no need for supplemental signs I guess.

Either you have a regular stop intersection, in which case there are octagonal stop signs on the roads that do not have priority. No supplemental signs needed. A driver stopping at the stop sign knows that when the intersection is clear he can drive. If it's a 4 way and he's turning left, he may have to yield to a driver on the opposite road, depending on the local laws (In a right hand yield priority the car turning left yields to the car in the opposite road).

Or it's a multi-way-stop (which is rare) in which case all roads have the supplemental sign. None of the roads have priority and all drivers can do to resolve deadlocks is be careful. All the supplemental sign does is inform drivers that OTHER drivers will also stop. It just removes the ambiguity we talked about above - where a driver at a stop sign might otherwise think he can't drive until the intersection is completely clear.