Sustrans signs showing time instead of distance

[mattheus]

For me it's that distance will be correct whereas times will be wrong (for virtually all cyclists).

The distance will not be correct: it might - we hope - be accurate within some tolerance.
We don't know the tolerance, even if there is one.

Me thinks you are splitting hairs. Any measurement is technically wrong. I use a digital micrometer and the measurement is wrong.

Ian

Yes of course you are right; but I'm trying to make a valid point. How accurate do you need this information to be?

[Psamathe]

The distance will not be correct: it might - we hope - be accurate within some tolerance.
We don't know the tolerance, even if there is one.

Me thinks you are splitting hairs. Any measurement is technically wrong. I use a digital micrometer and the measurement is wrong.

Ian

:lol:
Yes of course you are right; but I'm trying to make a valid point. How accurate do you need this information to be?

The time will be subject to the same errors and uncertainties as the mileage plus the significant variation in how fast people cycle. And there is a wide range of speeds people cycle at e.g. compare a family with <10 year old children on small bikes to an individual on carbon in lycra (ignoring my stereotyping).

Ian

[mattheus]

Me thinks you are splitting hairs. Any measurement is technically wrong. I use a digital micrometer and the measurement is wrong.

Ian

Yes of course you are right; but I'm trying to make a valid point. How accurate do you need this information to be?

The time will be subject to the same errors and uncertainties as the mileage plus the significant variation in how fast people cycle. And there is a wide range of speeds people cycle at e.g. compare a family with <10 year old children on small bikes to an individual on carbon in lycra (ignoring my stereotyping).

Ian

Doesn't answer the question ... so here's another one:

What purpose do these numbers serve? And for whom?

[Psamathe]

:lol:
Yes of course you are right; but I'm trying to make a valid point. How accurate do you need this information to be?

The time will be subject to the same errors and uncertainties as the mileage plus the significant variation in how fast people cycle. And there is a wide range of speeds people cycle at e.g. compare a family with <10 year old children on small bikes to an individual on carbon in lycra (ignoring my stereotyping).

Ian

Doesn't answer the question ... so here's another one:

What purpose do these numbers serve? And for whom?

Given the range of speeds possible I'd guess maybe cycling speed range could vary by a factor of 100%. So if a sign said "10 miles" and it was actually 20 miles you'd consider that excessive.

I suspect there is no answer to your new question. The signs will serve different purposes for different people and depending on the location.

Most people will already have an appreciation for signs in miles given that most road signs with distance use miles (exception maybe those indicating traffic conditions on roads where speeds of vehicles are similar).

Ian

[mjr]

Most people will already have an appreciation for signs in miles given that most road signs with distance use miles (exception maybe those indicating traffic conditions on roads where speeds of vehicles are similar).

But most people have no appreciation for how long it takes to cycle a given distance. I've seen that group rides advertised as 90 minutes average length attract more new riders than ones advertised as 15 miles.

(That doesn't mean I'm convinced that time signs are better.)

[Psamathe]

Most people will already have an appreciation for signs in miles given that most road signs with distance use miles (exception maybe those indicating traffic conditions on roads where speeds of vehicles are similar).

But most people have no appreciation for how long it takes to cycle a given distance. I've seen that group rides advertised as 90 minutes average length attract more new riders than ones advertised as 15 miles.

(That doesn't mean I'm convinced that time signs are better.)

Isn't that a different aspect. People being told 90 mins average means it's not an all day, they'll be back for lunch. A ride advertised as 30 mins might make people think not worth bothering with, a ride advertised as 4 hrs might make people thing "a bit much for me". Very different from how far to a specific place.

I can appreciate for group rides (presumably circular rides) a duration makes sense where a measure to destination I feel it doesn't.

Ian

[PH]

Given the range of speeds possible I'd guess maybe cycling speed range could vary by a factor of 100%. So if a sign said "10 miles" and it was actually 20 miles you'd consider that excessive.
Ian

I think you're making a case that doesn't exist.
For example - There's 4,000+ members in the Cycling UK Strava group, roughly 80% + of them have an average spreed between 12 - 16 mph, the difference over say 6 miles (30min) is going to be minimal. The racing cyclist and the family group are going to know it doesn't apply to them.
On an unknown route, I don't know how long it'll take me to ride 6 miles. How many traffic lights, junctions, hills, traffic, Sustrans barriers, riding steady looking out for signs, making better progress on a straightforward route...
Over 60 miles, I'll have a better idea, to some extent all the above are likely to average out. Even then I'll only know from experience how long X miles takes. It's only going to take a few examples before I know roughly how long X min takes.
I still think the main purpose of these signs is to make non cyclists consider cycling. I used to do the same when I commuted, if I had a conversation about it I'd say how long it took rather than how far it was. I've had some success getting people onto bikes, non riders will have a better idea what half an hour on a bike is rather than 6 miles.

[Psamathe]

Given the range of speeds possible I'd guess maybe cycling speed range could vary by a factor of 100%. So if a sign said "10 miles" and it was actually 20 miles you'd consider that excessive.
Ian

I think you're making a case that doesn't exist.
For example - There's 4,000+ members in the Cycling UK Strava group, roughly 80% + of them have an average spreed between 12 - 16 mph, the difference over say 6 miles (30min) is going to be minimal. The racing cyclist and the family group are going to know it doesn't apply to them.
On an unknown route, I don't know how long it'll take me to ride 6 miles. How many traffic lights, junctions, hills, traffic, Sustrans barriers, riding steady looking out for signs, making better progress on a straightforward route...
...

I certainly don't claim knowledge of all cyclists but also I have been stuck on cycle paths behind cyclists going horrendously slowly for long distances (how do many dutch cyclists ride so slowly and not fall off?).

I would suggest when you take a group on Strava then that is a narrow selection/self-selecting subset, people interested in recording their rides, logging, joining cycling groups, etc.

Why not sign in units that have meaning to both the racing cyclist and the family group rather than using units where both of those "are going to know it doesn't apply to them". Miles will apply to both and everybody in-between.

Ian

[PH]

Why not sign in units that have meaning to both the racing cyclist and the family group rather than using units where both of those "are going to know it doesn't apply to them". Miles will apply to both and everybody in-between.
Ian

Because as I've tried to point out several times, those units are only of use if you have the experience to know what they mean to the individual and knowing the distance between A&C tells us nothing about B.

[Psamathe]

Why not sign in units that have meaning to both the racing cyclist and the family group rather than using units where both of those "are going to know it doesn't apply to them". Miles will apply to both and everybody in-between.
Ian

Because as I've tried to point out several times, those units are only of use if you have the experience to know what they mean to the individual and knowing the distance between A&C tells us nothing about B.

I think we're in an "agree to disagree" point. It's not something impacting my blood pressure and I wont be writing to my MP about it. I think I've made my points for considering such signage daft and to repeat/summarise again would just be "seeking the last word".

Ian

[Bmblbzzz]

The truth is that neither distance nor time tell the full picture. Distance has the virtue of being "the same for everyone" but not all miles are the same (hills, slaloms, etc) (and thus in fact distance is not "the same for everyone" as different people react differently to hills etc). Time – well, it's covered above. And then there are factors like the weather on a particular day.

But I do note that time to the next junction is now often shown on motorway signs. Of course distance is already there.

[Bmblbzzz]

I wonder how the times on those signs were arrived at? Just by an assumed average speed, or was some allowance made for hills etc?

[rareposter]

Doesn't answer the question ... so here's another one:

What purpose do these numbers serve? And for whom?

People are TERRIBLE at judging distances.
However, you know that it takes 10 mins to walk to the station or 5 mins to walk to the chippy or 20 mins to drive to the big supermarket or 35 mins on the train into town.
You know that your journey to work is roughly 30 mins, the bus trip to Aunty Mabel always takes an hour...

This is used a lot in transport modelling - far more than distance - because it is more intuitive to the majority of people.

Regular cyclists in particular are usually far better at judging distance compared to (say) motorists, partly because so many use a cycle computer or apps like Strava and partly because the variations are so small. My journey to work (12 miles) on a bike always takes about 50 mins and that rarely varies by more than 5 mins due to weather, traffic etc.
That same journey in a car has taken me between 25 mins and 90 mins depending on traffic, weather, crashes, roadworks, time of day, local football matches etc - there are far more variables.

A 30 min trip in a car could be 3 miles in heavy urban traffic or it could be 30 miles on a motorway.
However if you said to a person in the street - ride 5 miles - they'd be like "that's far too far, I could never do that, it'd take all day".
Tell them that it's only a 30 min ride along tis nice path to the next town though and they'd be like "oh yeah, that sounds nice, I'll do that" (rather than drive).

I bet we've all experienced a version of this when someone at work says "how far did you ride?" and you say "10 miles" and they look at you like you've just ridden the Tour de France. 60 miles / 100km is doable in 4hrs on even a fairly average club run so try saying
"oh I rode for 4hrs" vs
"oh I rode 60 miles" vs
"oh I rode 100km"
and see the varying response. People simply don't know how far 60 miles or 100km actually are.

The fact that it won't be accurate for hardcore roadies or small children is largely irrelevant; it'll be mostly right for most people most of the time and you may even get some people going "pah, 10 minutes, I did it in 8, I'm awesome!" or conversely "well it says 10 mins but I just took my time and stopped a bit and still did it in 12!"

[mattheus]

Thank you Mr Poster. Good explanation

[ChrisF]

If the signposted routes are on shared-use paths I can understand the timings - they don't want cyclists riding too fast. Some cycle paths in Europe have maximum speed limits (e.g. 10 kph) although no-one seems to stick to them.