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Is Every Speed Limit Too Low?

Started by cpzilliacus, April 26, 2017, 09:40:52 AM

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vdeane

Quote from: kalvado on May 05, 2017, 02:02:28 PM
Did you ever drive from 7 to 87 north?
There is a good 3 lane funneled into 1 lane and another lane from light-controlled entrance (irregular) merged in on top of that.. If you think people merging at that spot can do 55, i think you didn't actually tried that during rush hour. And yes, traffic count of 13k one way and 21k the other way sounds a bit funny.. I would say probably 20K is about right - all merging from 1 lane...
And if we're talking urban/suburban with 1 -2 miles between exits, you need to move over quite often...
Not at rush hour, but I get a feeling it's free flowing up until someone cuts someone else off.  That's how it works at exit 4, which has similar issues at a smaller scale.  I've seen traffic go from free flowing to parking lot in the time it takes me to go from the bridge to the ramp.  Whenever I merge onto the Northway, 99% of the time I have zero trouble finding a gap to slip into... even when all the other people are cutting across the gore lines and butting in at 30-40 mph (creating a parking lot) even before the acceleration lane even begins!  People here are just scared of accelerating on ramps and using acceleration lanes for some reason (unfortunately, this timidness extends to virtually everything and everywhere else with respect to driving in the Capital District except for downtown Albany (where I've actually been honked at for things like not exceeding the speed limit by 10 mph, not running a red light, and not running over a pedestrian) for some reason).

Quote from: kalvado on May 05, 2017, 02:05:36 PM
Quote from: kphoger on May 05, 2017, 01:54:34 PM
Quote from: vdeane on May 05, 2017, 01:45:37 PM
Quote from: kalvado on May 05, 2017, 07:35:17 AM
OK, let me understand this.. SOmeone can drive 100 MPH and not keep right, because "Keep right" is a major reason why Germany can have roads without speed limits?

Hmmm.. some new concept here..

If they're going 100 mph, they're probably spending the majority of their time passing.

Exactly.  And did I say something about people not keeping right while going 100 mph?  No, I don't believe I did.  Should read like this:

Someone can drive 100 MPH and not keep right, because "Keep right" is a major reason why Germany can have roads without speed limits.
Hmmm... SOmeone wants to have a cake and eat it too?
Quote from: kphoger on May 05, 2017, 12:13:02 PM

It relates because in Germany there is a very wide range of speeds encountered on the highway.  With more restrictive speed limits, the range of speeds encountered is narrower, and therefore the frequency of lane use conflict also decreases.  Or, to put it another way, a guy legally driving 100 mph is going to encounter fewer obstacles if the left lane is kept clear than if it isn't.
Question is - where that 100 MPH car actually is driving so that he is bothered about obstacles in left lane?
The autobahn has too much traffic for someone to go 100 mph in the right lane for long periods of time.  From what I've read, think the Thruway in the finger lakes during Labor Day weekend.  All the time.
Please note: All comments here represent my own personal opinion and do not reflect the official position of NYSDOT or its affiliates.


kphoger

Quote from: kalvado on May 05, 2017, 02:02:28 PM
And not bothering to return to right lane... Let me see what it looks like.. Oh, yes, split speed limits!

Quote from: kalvado on May 05, 2017, 02:05:36 PM
Quote from: kphoger on May 05, 2017, 01:54:34 PM
Quote from: vdeane on May 05, 2017, 01:45:37 PM
Quote from: kalvado on May 05, 2017, 07:35:17 AM
OK, let me understand this.. SOmeone can drive 100 MPH and not keep right, because "Keep right" is a major reason why Germany can have roads without speed limits?

Hmmm.. some new concept here..

If they're going 100 mph, they're probably spending the majority of their time passing.

Exactly.  And did I say something about people not keeping right while going 100 mph?  No, I don't believe I did.  Should read like this:

Someone can drive 100 MPH and not keep right, because "Keep right" is a major reason why Germany can have roads without speed limits.
Hmmm... SOmeone wants to have a cake and eat it too?
Quote from: kphoger on May 05, 2017, 12:13:02 PM

It relates because in Germany there is a very wide range of speeds encountered on the highway.  With more restrictive speed limits, the range of speeds encountered is narrower, and therefore the frequency of lane use conflict also decreases.  Or, to put it another way, a guy legally driving 100 mph is going to encounter fewer obstacles if the left lane is kept clear than if it isn't.
Question is - where that 100 MPH car actually is driving so that he is bothered about obstacles in left lane?

Again, I never suggested not returning to the left lane.  You keep saying I said that, but I didn't.

Want to drive 100 mph?  Go ahead!  Stay in the right lane until you need to pass someone.  Move left, pass the other vehicle, move back into the right lane.  Or, if traffic is thick, there might not be as much moving back into the right lane, but that's as expected.  Someone coming up from behind at 120 mph?  Get the heck over at the earliest opportunity.  Absolute speed has little to do with how you choose your lane.  Two basic rules apply:  (1) keep right unless you have a reason to be in the left lane, and (2) pass on the left.

Contrast that to a highway where keeping right is not part of the culture.  Drive 100 mph, then encounter a cluster of vehicles, and have no idea which lane you need to be in to continue past them.  The guy in the left lane is going basically the same speed as the guy in the right lane, maybe even slower, who the heck knows?  Gotta slow down to their speed to figure it out, change lanes as you determine, then get back up to 100 mph, and do it all over again at the next cluster of vehicles.  There are your obstacles.

And yes, I've been on the Autobahn (as a passenger only).  Both in a passenger vehicle going 90-95 mph and also in a Fiat RV (five speed stick shift on the column) that never topped 70 mph.
Keep right except to pass.  Yes.  You.
Visit scenic Orleans County, NY!
Male pronouns, please.

Quote from: Philip K. DickIf you can control the meaning of words, you can control the people who must use them.

kalvado

Quote from: kphoger on May 05, 2017, 02:28:30 PM
Quote from: kalvado on May 05, 2017, 02:02:28 PM
And not bothering to return to right lane... Let me see what it looks like.. Oh, yes, split speed limits!

Quote from: kalvado on May 05, 2017, 02:05:36 PM
Quote from: kphoger on May 05, 2017, 01:54:34 PM
Quote from: vdeane on May 05, 2017, 01:45:37 PM
Quote from: kalvado on May 05, 2017, 07:35:17 AM
OK, let me understand this.. SOmeone can drive 100 MPH and not keep right, because "Keep right" is a major reason why Germany can have roads without speed limits?

Hmmm.. some new concept here..

If they're going 100 mph, they're probably spending the majority of their time passing.

Exactly.  And did I say something about people not keeping right while going 100 mph?  No, I don't believe I did.  Should read like this:

Someone can drive 100 MPH and not keep right, because "Keep right" is a major reason why Germany can have roads without speed limits.
Hmmm... SOmeone wants to have a cake and eat it too?
Quote from: kphoger on May 05, 2017, 12:13:02 PM

It relates because in Germany there is a very wide range of speeds encountered on the highway.  With more restrictive speed limits, the range of speeds encountered is narrower, and therefore the frequency of lane use conflict also decreases.  Or, to put it another way, a guy legally driving 100 mph is going to encounter fewer obstacles if the left lane is kept clear than if it isn't.
Question is - where that 100 MPH car actually is driving so that he is bothered about obstacles in left lane?

Again, I never suggested not returning to the left lane.  You keep saying I said that, but I didn't.

Want to drive 100 mph?  Go ahead!  Stay in the right lane until you need to pass someone.  Move left, pass the other vehicle, move back into the right lane.  Or, if traffic is thick, there might not be as much moving back into the right lane, but that's as expected.  Someone coming up from behind at 120 mph?  Get the heck over at the earliest opportunity.  Absolute speed has little to do with how you choose your lane.  Two basic rules apply:  (1) keep right unless you have a reason to be in the left lane, and (2) pass on the left.

Contrast that to a highway where keeping right is not part of the culture.  Drive 100 mph, then encounter a cluster of vehicles, and have no idea which lane you need to be in to continue past them.  The guy in the left lane is going basically the same speed as the guy in the right lane, maybe even slower, who the heck knows?  Gotta slow down to their speed to figure it out, change lanes as you determine, then get back up to 100 mph, and do it all over again at the next cluster of vehicles.  There are your obstacles.

And yes, I've been on the Autobahn (as a passenger only).  Both in a passenger vehicle going 90-95 mph and also in a Fiat RV (five speed stick shift on the column) that never topped 70 mph.

If you don't realize that, driving pattern you suggest is a safety nightmare. FOr one, because passing at a smaller speed differential becomes a russian roulette that someone else going 60 MPH above your speed may make contact with your bumper because you didn't see them.. 
Actually lane change is already a relatively high risk step - compared to staying in lane.

kphoger

Quote from: kalvado on May 05, 2017, 02:39:51 PM
Quote from: kphoger on May 05, 2017, 02:28:30 PM
Quote from: kalvado on May 05, 2017, 02:02:28 PM
Quote from: kalvado on May 05, 2017, 02:05:36 PM
Quote from: kphoger on May 05, 2017, 01:54:34 PM
Quote from: vdeane on May 05, 2017, 01:45:37 PM
Quote from: kalvado on May 05, 2017, 07:35:17 AM
Quote from: kphoger on May 05, 2017, 12:13:02 PM
If you don't realize that, driving pattern you suggest is a safety nightmare. FOr one, because passing at a smaller speed differential becomes a russian roulette that someone else going 60 MPH above your speed may make contact with your bumper because you didn't see them.. 
Actually lane change is already a relatively high risk step - compared to staying in lane.

(Sorry, but these nested posts were getting out of control.  :-/ )

I agree that, in heavy traffic, staying in your lane is best both for driver safety and efficiency of the road, but it's also in heavy traffic that fast-driving traffic is not as likely to have any room to move right in the first place.  In sparser traffic, where there is actually room and time to move right, I'd say the risk in doing so is inherently less.
Keep right except to pass.  Yes.  You.
Visit scenic Orleans County, NY!
Male pronouns, please.

Quote from: Philip K. DickIf you can control the meaning of words, you can control the people who must use them.

kalvado

Quote from: kphoger on May 05, 2017, 03:08:53 PM


(Sorry, but these nested posts were getting out of control.  :-/ )

I agree that, in heavy traffic, staying in your lane is best both for driver safety and efficiency of the road, but it's also in heavy traffic that fast-driving traffic is not as likely to have any room to move right in the first place.  In sparser traffic, where there is actually room and time to move right, I'd say the risk in doing so is inherently less.
(trimming it even further!)
Well, for me that boils down to a simple statement:
"keep right" is applicable at relatively small traffic density window. less than 100-200 VPH, and nobody cares. More than 1500-2000 VPH, and right lane is now blocked rock solid, no way for entering vehicles to get in (and now room for move over, second lane is also dense)
Same story as with roundabouts - a niche solution is promoted as absolute one.

kphoger

Quote from: kalvado on May 05, 2017, 03:13:21 PM
Quote from: kphoger on May 05, 2017, 03:08:53 PM


(Sorry, but these nested posts were getting out of control.  :-/ )

I agree that, in heavy traffic, staying in your lane is best both for driver safety and efficiency of the road, but it's also in heavy traffic that fast-driving traffic is not as likely to have any room to move right in the first place.  In sparser traffic, where there is actually room and time to move right, I'd say the risk in doing so is inherently less.
(trimming it even further!)
Well, for me that boils down to a simple statement:
"keep right" is applicable at relatively small traffic density window. less than 100-200 VPH, and nobody cares. More than 1500-2000 VPH, and right lane is now blocked rock solid, no way for entering vehicles to get in (and now room for move over, second lane is also dense)
Same story as with roundabouts - a niche solution is promoted as absolute one.

So what happens between 100-200 and 1500-2000 vph?
Keep right except to pass.  Yes.  You.
Visit scenic Orleans County, NY!
Male pronouns, please.

Quote from: Philip K. DickIf you can control the meaning of words, you can control the people who must use them.

kalvado

Quote from: kphoger on May 05, 2017, 04:24:01 PM
Quote from: kalvado on May 05, 2017, 03:13:21 PM
Quote from: kphoger on May 05, 2017, 03:08:53 PM


(Sorry, but these nested posts were getting out of control.  :-/ )

I agree that, in heavy traffic, staying in your lane is best both for driver safety and efficiency of the road, but it's also in heavy traffic that fast-driving traffic is not as likely to have any room to move right in the first place.  In sparser traffic, where there is actually room and time to move right, I'd say the risk in doing so is inherently less.
(trimming it even further!)
Well, for me that boils down to a simple statement:
"keep right" is applicable at relatively small traffic density window. less than 100-200 VPH, and nobody cares. More than 1500-2000 VPH, and right lane is now blocked rock solid, no way for entering vehicles to get in (and now room for move over, second lane is also dense)
Same story as with roundabouts - a niche solution is promoted as absolute one.

So what happens between 100-200 and 1500-2000 vph?
ANd over there a lot of things may happen. Including situation, when separation between vehicles in right lane is sparse enough, but overall count is high enough for keep right to make sense. That is why I call the issue "keep right no matter what".

UCFKnights

I didn't mean to bring this off topic, but clearly I wasn't saying or intending that you have to go back to the right lane in every single gap. But if you aren't passing somebody and won't be for over, say, 30 seconds , you should get back to the right. The fact is its safer for you to do the extra lane changes then to force the people behind you to go to the right and pass you on the right. People generally shouldn't be ABLE to pass you on the right (ignoring assholes who are cutting people off to do it and forcing people to hit their breaks to accommodate it)

It drives me nuts here how when I'm trying to go 79mph, the person enters the 3 lane highway at 70mph, immediately goes to the center lane even though no one is in the right lane because "they don't want to have to worry about vehicles merging at the next entrance", which causes the person in the center lane to move to the left at their speed of 75 mph, and i'm forced to slow down to 75mph while he passes, or I can easily maintain my speed by just moving myself all the way to the right lane which no one seems to want to use. Seems to happen everyday here, and for many of the faster drivers, they're stuck between trying to use the left lane to pass, and then being forced to use the empty right lane if they want to pass.

Duke87

Quote from: UCFKnights on May 05, 2017, 07:34:08 PM
It drives me nuts here how when I'm trying to go 79mph, the person enters the 3 lane highway at 70mph, immediately goes to the center lane even though no one is in the right lane because "they don't want to have to worry about vehicles merging at the next entrance", which causes the person in the center lane to move to the left at their speed of 75 mph, and i'm forced to slow down to 75mph while he passes, or I can easily maintain my speed by just moving myself all the way to the right lane which no one seems to want to use. Seems to happen everyday here, and for many of the faster drivers, they're stuck between trying to use the left lane to pass, and then being forced to use the empty right lane if they want to pass.

I don't want to be forced to slow down to 45-50 at every entrance ramp because that's the speed people merge at any more than you want to be forced to slow down to 75 because that's as fast as the person in front of you is passing at.

If you always take the same road, you will never see anything new.

UCFKnights

Quote from: Duke87 on May 06, 2017, 01:20:36 AM
Quote from: UCFKnights on May 05, 2017, 07:34:08 PM
It drives me nuts here how when I'm trying to go 79mph, the person enters the 3 lane highway at 70mph, immediately goes to the center lane even though no one is in the right lane because "they don't want to have to worry about vehicles merging at the next entrance", which causes the person in the center lane to move to the left at their speed of 75 mph, and i'm forced to slow down to 75mph while he passes, or I can easily maintain my speed by just moving myself all the way to the right lane which no one seems to want to use. Seems to happen everyday here, and for many of the faster drivers, they're stuck between trying to use the left lane to pass, and then being forced to use the empty right lane if they want to pass.

I don't want to be forced to slow down to 45-50 at every entrance ramp because that's the speed people merge at any more than you want to be forced to slow down to 75 because that's as fast as the person in front of you is passing at.
I think everyone agrees if someone is merging at a slower speed in front of you, you should move to the left to pass them, before you're required to slow down. Then after you pass that merging traffic, you move to the right. Its really not complicated, and only required a single lane change for a single car without anyone slowing down, instead of the alternative requiring multiple cars to change lanes and people to pass on the right to maintain the flow.

kphoger

We've had enough threads get hijacked into an argument about the right lane.
Let's get back to the topic.
Keep right except to pass.  Yes.  You.
Visit scenic Orleans County, NY!
Male pronouns, please.

Quote from: Philip K. DickIf you can control the meaning of words, you can control the people who must use them.

kalvado

Quote from: kphoger on May 08, 2017, 12:36:50 PM
We've had enough threads get hijacked into an argument about the right lane.
Let's get back to the topic.
And I think this is relevant. This is about overall arrangement of road traffic. One of speed limit considerations should be managability of merge. Sure. I can step on a gas and get to traffic flow (SL+20) by the end of long ramp near my place. Those with NJ plates going faster than that in right lane are free to do some brakes check.  I saw many trucks struggling with that. Heck, they are struggling with achieving speed limit on that uphill ramp.  But from the formal perspective that means speed limit is too high, isn't it?

Brandon

Quote from: kalvado on May 08, 2017, 04:56:57 PM
Quote from: kphoger on May 08, 2017, 12:36:50 PM
We've had enough threads get hijacked into an argument about the right lane.
Let's get back to the topic.
And I think this is relevant. This is about overall arrangement of road traffic. One of speed limit considerations should be managability of merge. Sure. I can step on a gas and get to traffic flow (SL+20) by the end of long ramp near my place. Those with NJ plates going faster than that in right lane are free to do some brakes check.  I saw many trucks struggling with that. Heck, they are struggling with achieving speed limit on that uphill ramp.  But from the formal perspective that means speed limit is too high, isn't it?

It could also mean that you're not using the ramp for its intended purpose, as the acceleration lane to merge smoothly onto the freeway.  Rule of thumb, you should be near the speed limit at the end of the ramp.
"If you think this has a happy ending, you haven't been paying attention." - Ramsay Bolton

"Symbolic of his struggle against reality." - Reg

kalvado

Quote from: Brandon on May 08, 2017, 05:34:01 PM
Quote from: kalvado on May 08, 2017, 04:56:57 PM
Quote from: kphoger on May 08, 2017, 12:36:50 PM
We've had enough threads get hijacked into an argument about the right lane.
Let's get back to the topic.
And I think this is relevant. This is about overall arrangement of road traffic. One of speed limit considerations should be managability of merge. Sure. I can step on a gas and get to traffic flow (SL+20) by the end of long ramp near my place. Those with NJ plates going faster than that in right lane are free to do some brakes check.  I saw many trucks struggling with that. Heck, they are struggling with achieving speed limit on that uphill ramp.  But from the formal perspective that means speed limit is too high, isn't it?

It could also mean that you're not using the ramp for its intended purpose, as the acceleration lane to merge smoothly onto the freeway.  Rule of thumb, you should be near the speed limit at the end of the ramp.
To merge smoothly or to  be near the speed limit? Former requires going much faster, later makes merge messy...

michravera

Quote from: jeffandnicole on May 04, 2017, 06:12:57 AM
Quote from: wxfree on May 04, 2017, 03:05:36 AM
Regarding the 85th percentile, what I read about it gave me the impression (although I may have been reading too much into it) that the real point wasn't the "85" number but was the shape of the speed distribution curve.  To describe, if the 85th percentile speed was 73, there may be in a survey several cars going 71, several going 72, and several going 73, while maybe there are fewer going 74, only a couple going 75, maybe one or two going 76, another going 78, a few more in the 80s, and so on.  The 85th percentile represents the highest speed with a cluster rather than a rarity of presumably reasonable drivers selecting that speed.  Those going faster have fewer other drivers choosing their speed, showing that they may be demonstrating reckless disregard for safety.  The point is that the 85th percentile itself may not be a magic number, but just an average of where the shape of the distribution curve starts to change.  If the clusters change to isolated examples at a lower or higher speed, then that speed may warrant consideration as the limit.  Based on the way it was described, that's what I took from it.


85th percentile has nothing to do with clustering or a bell curve.

The NJDOT website does a good, simple job in explaining the 85th percentile. 

http://www.state.nj.us/transportation/refdata/roadway/speed.shtm

Quote
Average speed or mean speed is the sum of all individual speed measurements divided by the total number of vehicles.

Median speed - the speed at or below 50 percent of vehicles travel.

85th percentile speed - the speeds at or below 85% of all vehicles are observed to travel under free flowing conditions.

Setting the speed limit to the 85th%tile speed and allowing a 10% tolerance for enforcement is sort of like grading students. Those at the 85%tile get a B. Those within 10% above get an A. Those who are faster than that don't belong in the class.

cpzilliacus

Quote from: Duke87 on May 06, 2017, 11:39:29 AM
Meanwhile there tends to be enough traffic that I cannot just quickly dart into the center lane. Or, even if there is a gap, NY drivers have this uncanny habit of reacting to turn signals as an invitation to speed up and prevent you from changing lanes because how dare you try to get in front of them. Which leaves slowing down as the only way to avoid crashing into the maniacs who don't know what "yield" means.

This is not limited to New York City and environs.  I think  it fair to say that many drivers in the Northeast (defined for the purposes of this discussion as someplace in Virginia to the U.S./Canada border) do that.

One of the joys of driving in California is that most drivers will let you in if you signal. Of course, the driving population is large enough that asinine drivers and driving habits can be found even in the Golden  State.
Opinions expressed here on AAROADS are strictly personal and mine alone, and do not reflect policies or positions of MWCOG, NCRTPB or their member federal, state, county and municipal governments or any other agency.

slorydn1

As much as I fuss about my local drivers, the one good thing they will do is let someone in if they need it (all bets are off just 2 hours west in Raliegh, though).
Please Note: All posts represent my personal opinions and do not represent those of any governmental agency, non-governmental agency, quasi-governmental agency or wanna be governmental agency

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