Cycling UK Forum

De Sisti wrote:

LollyKat wrote:
Rear lights used to flash quite slowly and I found it difficult to judge how far away they were, but the modern fast ones don't cause me such problems. I use two lights both front and rear, with one set to constant, the other flashing.

How accurate does your judgement of the distance have to be? Just askin'?

If I couldn't judge the distance then I couldn't judge the speed, and how fast (in a car) I was catching up the bike. I'm thinking of quite a number of years ago, when there was far less use of hi-vis and reflectives, so that the slow-flashing rear light was frequently the only thing to be seen at first.

Lollykat wrote:If I couldn't judge the distance then I couldn't judge the speed, and how fast (in a car) I was catching up the bike. I'm thinking of quite a number of years ago, when there was far less use of hi-vis and reflectives, so that the slow-flashing rear light was frequently the only thing to be seen at first.

When in a car just think the following; Flashing red light ahead, must be a cyclist, probably travelling
at less than 30 mph, adjust my driving accordingly and {FFE - family-friendly edit } don't crash into him/her. Easy innit.

Of course - I was only confirming other reports that ?some / ?a lot of people find it harder to judge the distance of a slow-flashing light. As a regular cyclist I am always careful around them when in the car, but as we all know to our cost some / a lot of drivers are not.

No one has mentioned the fact that when in flashing mode battery life is significantly extended. Personally I use it to that end usually around dusk.

As far as I can tell from relevant research, at night, rate of change of the distance of a vehicle from the point of view of a moving observer is gauged by 'rate of looming'.

That is the rate at which the distance between two fixed points on the retina of the eye increases.

In my opinion it would seem to best illicit this natural measure, that two lights both on constant not flash should be used, and the lights should be As physically large and bright as practically possible and separated by a reasonable amount.

see here:
http://www.visualexpert.com/Resources/r ... ision.html

http://www.kovan.ceng.metu.edu.tr/pub/h ... node2.html

Or better have lights which flash in sequence inwards ?

Some people are of the opinion that allowing the motorist to judge the distance and your position more precisely is of benefit, so in that case you want a constant light source.

Personally, I believe that leaving the motorist aware of your presence but unable to precisely position you is a better outcome. I have far far fewer close passes at night and I put this down to motorists finding it harder to judge my position so precisely (regardless of what lights I have). I think the same thing happens with night driving and all vehicles.

De Sisti wrote:

Lollykat wrote:If I couldn't judge the distance then I couldn't judge the speed, and how fast (in a car) I was catching up the bike. I'm thinking of quite a number of years ago, when there was far less use of hi-vis and reflectives, so that the slow-flashing rear light was frequently the only thing to be seen at first.

When in a car just think the following; Flashing red light ahead, must be a cyclist, probably travelling
at less than 30 mph, adjust my driving accordingly and {FFE - family-friendly edit } don't crash into him/her. Easy innit.

Or "bl00dy cyclist with there stupid puny blinky lights , lets see how closee can get to this cyclist and how much of the b'jesus I can scare out of them"

the thing is with visual looming, is that it is an innate, instinctive response built in to the animal side of our brains. It does not require a conscious decision. In my opinion you need to emphasise those instinctive reacions in an approaching driver, not expect them to make an intelligent decision.
I have a dinotte 300r on the seat post and a knog blinder on my helmet on constant both. (night and day) both these are recharged daily.

[quote="meic"I have far far fewer close passes at night and I put this down to motorists finding it harder to judge my position so precisely [/quote]

Me too. As long as drivers see me and recognise me as a bike then I'm not too worried about whether they can judge how far away I am. I run 2 or 3 rear flashers.

I am of the opinion that the minute you are identified as a cyclist per se, then you are treated more irresponsibly by a sizeable minority of motorists. Id rather make myself look as much as possible like the generic vehicle on the road that I am and hopefully get treated like one.

read this;
http://www.visualexpert.com/Resources/r ... ision.html

and moreover the "MOTH EFFECT":

http://www.visualexpert.com/Resources/motheffect.html

All this presumes that the only thing that matters is that the driver sees you and focuses as much attention as possible on you. Surely this is wrong - we want drivers to be alert to everything out there - not just us.

I don't want a driver distractedly trying to gauge what I am, how far away I am and how fast I'm moving. Because while my flashing lights are grabbing a disproportionate amount of his attention, he might miss something else which also requires attention - perhaps another cyclist, or a pedestrian, or the fact that he's drifting towards the oncoming traffic. When he drags his eyes away from your confusing and mesmerising blinking lights and sees the other hazard, it could be curtains for the other cyclist, the pedestrian, the driver himself - or you. It's bad if a driver crashes into you, but it can be just as bad if he crashes into something else when you're close by.

I want drivers on the road to be giving their full attention to the whole road situation, not just me. That's why I hate flashing lights - I KNOW they distract me from staying as fully attentive as I can be to EVERYTHING that's going on around me, and I reckon they do the same to other road users, too.

PaulCumbria wrote:All this presumes that the only thing that matters is that the driver sees you and focuses as much attention as possible on you. Surely this is wrong - we want drivers to be alert to everything out there - not just us.

I don't want a driver distractedly trying to gauge what I am, how far away I am and how fast I'm moving. Because while my flashing lights are grabbing a disproportionate amount of his attention, he might miss something else which also requires attention - perhaps another cyclist, or a pedestrian, or the fact that he's drifting towards the oncoming traffic. When he drags his eyes away from your confusing and mesmerising blinking lights and sees the other hazard, it could be curtains for the other cyclist, the pedestrian, the driver himself - or you. It's bad if a driver crashes into you, but it can be just as bad if he crashes into something else when you're close by.

I want drivers on the road to be giving their full attention to the whole road situation, not just me. That's why I hate flashing lights - I KNOW they distract me from staying as fully attentive as I can be to EVERYTHING that's going on around me, and I reckon they do the same to other road users, too.

The erratic ones can - but the steady (i.e. legal) blinking lights don't do that significantly. They act as an excellent identifier amongst the sea of brighter, but steady, car lights in an urban situation, and as a warning of a "not doing 60mph" vehicle in a rural setting.

I can't recall if erratic blinking is allowed - it was suggested up thread that it was, but I can't recall if additional lights have to obey both colour and flashing regulations, or just colour - I'm leaning towards just colour at the moment.

PaulCumbria wrote:
I don't want a driver distractedly trying to gauge what I am, how far away I am and how fast I'm moving. Because while my flashing lights are grabbing a disproportionate amount of his attention, he might miss something else which also requires attention - perhaps another cyclist, or a pedestrian, or the fact that he's drifting towards the oncoming traffic.

When he drags his eyes away from your confusing and mesmerising blinking lights and sees the other hazard, it could be curtains for the other cyclist, the pedestrian, the driver himself - or you. It's bad if a driver crashes into you, but it can be just as bad if he crashes into something else when you're close by.

How do you know that the situation you've mention applies to anyone other than yourself?

I want drivers on the road to be giving their full attention to the whole road situation, not just me. That's why I hate flashing lights - I KNOW they distract me from staying as fully attentive as I can be to EVERYTHING that's going on around me, and I reckon they do the same to other road users, too.

Do you have a source that proves that flashing lights distract other road users, and if so, how many (percentage wise)?

thirdcrank wrote:For all I know, there may be other signals available, but like the majority of road users I can't read morse code.

Indeed. The International Alpine Distress Signal is six flashes (or blasts on a whistle), repeated at one minute intervals. The reply is three.

meic wrote:New cars have to be manufactured with day time lights, Volvos have had them for years as have many motorcycles, the same logic should apply even more so to cyclists as they are the slimmest (so easiest) things on the road to miss.

Petrol is alot cheaper source of energy than batteries!

meic wrote:Some people are of the opinion that allowing the motorist to judge the distance and your position more precisely is of benefit, so in that case you want a constant light source.

Personally, I believe that leaving the motorist aware of your presence but unable to precisely position you is a better outcome. I have far far fewer close passes at night and I put this down to motorists finding it harder to judge my position so precisely (regardless of what lights I have). I think the same thing happens with night driving and all vehicles.

I agree, this is the argument from risk compensation, the more confused they are the more risk they perceive, and the more care they take. In his book Traffic, Vanderbilt makes the same point about cyclists who don't signal.