Are flashing cycle lights safe?

[asfeeley]

I find the new breed of cycle lights to be too bright and when they are flashing they present a hazard. They can create such a glare around the figure of the cyclist that it is not possible to detect hand signals, especially when the cyclist is wearing black/dark lycra. A solid or constant light allows the eye to follow and judge the movement, direction and speed of a cyclist while the interval between darkness and glare is sufficient to remove the cyclist from sight. During this interval, at speed, a cyclist and/or oncoming motorist may have changed their proximity to a fellow road user. Does anyone have a similar point of view?

[mercalia]

strange my view is just the opposite. flashing lights more visible at a distance and dont assault unlike the super bright constant lights aimed directly ahead ( not at the road )

[tatanab]

Front light or rear light?
I've had occasion where flashing rear lights are so bright all I want to do is get away from it as quickly as possible since I was unable to see past it.
Flashing front lights I suppose are for daytime use; at night they would be hopeless in the lanes where a constant light is need to see with (MTB riders note - too see with not to rip the retinas from other road users). When driving, in daytime, I have passed a cyclist whose flashing front light was truly objectionable.

[gaz]

I find the new breed of cycle lights to be too bright and when they are flashing they present a hazard. ...

Welcome to the forum.

Using lights that dazzle other road users is hazardous. Lights that dazzle may be flashing, they may be constant, they may be on a bicycle, they may be on another vehicle. It is not a good idea to dazzle other road users.

Natural light can dazzle.

If you are dazzled when cycling or driving, whatever the cause of such dazzle, it is not a good idea to carry on regardless. Slow down and if necessary stop. It would be hazardous not to do so.

[kwackers]

Flashing or not, there's a new breed of super bright cheap LED lights that are positively dangerous. Twice now on unlit paths I've had to stop because I can't see where I'm going after being blinded by oncoming cyclists and even on lit roads they can be uncomfortably bright.

It's the usual thing; makes *them* feel safer so they don't care what you think. I'm seriously tempted to make my own stupidly bright one just to 'flash' the oncoming bike in order to make a point.

I'm not sure the flashing is necessarily any worse though.

[Paulatic]

I find the new breed of cycle lights to be too bright and when they are flashing they present a hazard. They can create such a glare around the figure of the cyclist that it is not possible to detect hand signals, especially when the cyclist is wearing black/dark lycra. A solid or constant light allows the eye to follow and judge the movement, direction and speed of a cyclist while the interval between darkness and glare is sufficient to remove the cyclist from sight. During this interval, at speed, a cyclist and/or oncoming motorist may have changed their proximity to a fellow road user. Does anyone have a similar point of view?

I'm not sure what you are getting at so I have a number of questions.
Are you saying 'the new breed of lights' are OK when steady?
Do you know if the lamps you are referring to are fitted correctly?
Is the glare around these cyclists different to the glare created by car headlights?
Why is it harder to see a dark 'lycra' clad arm than say a dark Gortex jacket arm?
I agree a steady light helps to place and determine the speed of a cycle. Knowing that a lamp at 4Hz travelling at 20 mph could travel 2metres between flashes I doubt it's any excuse to say I didn't see you there at that point.
I do find some modern car headlights are becoming very bright even when dipped.

[drossall]

As far as I know, the available research is that flashing lights are better at attracting attention, but worse at allowing the other road user to assess how far away you are. So, you are seen, but get hit anyway because the driver wasn't expecting to catch up with you at that precise moment.

Advice has always been to use two lights - one flashing, for visibility, and one steady, to fix your position. That's what I do.

Brightness is a different question, applying, as far as I can see, to both flashing and steady lights.

[ChrisOntLancs]

i have seen a lot of people treat "to see" lights as if they were "to be seen" lights. i often see ultra bright flashers on dark country lanes and i imagine the effect for the rider to be either hilarious or terrifying.

"to be seen" lights are getting brighter but setting them to flash is fine as long as it isn't at eye level for motorists when they're right behind you. seat post is bad, helmet, seat stays, and possibly rucksack are good.

a nifty trick if you want something flashing at eye level, point it at something else. i used to point a rear light up towards my seat creating a sort of lamp shade effect.

[nez]

I recently bought a 'see sense' rear light and I have to say it does seem to encourage people to give me a wider berth when passing. So 'new flashing lights' = no problem for me. I run it during the day, by the way.

[ianrobo]

As far as I know, the available research is that flashing lights are better at attracting attention, but worse at allowing the other road user to assess how far away you are. So, you are seen, but get hit anyway because the driver wasn't expecting to catch up with you at that precise moment.

Advice has always been to use two lights - one flashing, for visibility, and one steady, to fix your position. That's what I do.

Brightness is a different question, applying, as far as I can see, to both flashing and steady lights.

good points, it is why on the front I have a light that does not flash but kind of fades in and out. As to the back I have one steady and one flashing after reading a piece that is the way to go.

[tykeboy2003]

I never use flashing lights and in lit streets only use a front light which wouldn't dazzle other road users. I do have a very bright light but only ever use it when off-road or in unlit areas, and always turn it off when confronted by oncoming traffic - unless the ingnorant so-and-sos fail to dip their lights for me.

Flashing lights tell drivers instantly that you're a cyclist and hence unworthy of consideration. Keep 'em guessing.

[iviehoff]

Part of the issue with flashing lights is that the government's daft regulations actually requires lights of certain types to be flashing. Not that many of the lights you can buy in fact comply exactly with the regulations, which are written on the assumption we mostly use carbon filament lights.

There are superbright lights and superbright lights. I have a couple of sets of superbright lights, though at 200-400 lumen they fall well short of being the very brightest. My cheaper superbright lights are much more dazzling than my expensive ones (twice the price). The expensive ones are well designed and ensure that you are spotted from at least 100yds without excessive dazzle.

I think the underlying reason for cyclists using superbright lights is SMIDSY. Cyclists reasonably wish to ensure that there is no possible excuse for SMIDSY. No one could possibly overlook you, even in a busy street scene with numerous other lights. After I had had several complaints about my cheaper back light from taxi drivers and other cyclists, my reaction was, well at least there was no chance that they would overlook me. However I do now use that light on a different, non-flashing, setting, and I haven't had any more complaints, rather I have had cyclists ask me to advise them what it is so they can get one too.

Since I have had 25 years of cycling to learn that motorists often take no notice whatsoever of my outstretched right arm, even in broad daylight when they can certainly see it, I'm not really too bothered if they can't see it too well. Much more important that they can see me.

[blinkered]

Flashing or not, there's a new breed of super bright cheap LED lights that are positively dangerous. Twice now on unlit paths I've had to stop because I can't see where I'm going after being blinded by oncoming cyclists and even on lit roads they can be uncomfortably bright.
...
.

This is my experience also. My commute has about 4 miles of unlit canal and river paths. At this time of year I am regularly dazzled by oncoming cyclists with very bright lights. I assumed they are either cheap lights and are spraying light all over the place or poorly setup.

[Flinders]

A curious thing this morning.
OH was driving, stopped at a junction. Waited for a cyclist to pass, then turned into the road behind him, commenting- 'there's a problem there with him just having a front light on his helmet- as he was coming downhill, he looked like he was further away, making it more difficult to judge when he'd be at the junction'.
When we passed the cyclist a little later on, he did have a front light on the bars, but it wasn't working, so probably normally he had both, which is a good idea. But I hadn't thought of the distance aspect if the only light was high up from the road, on a slope.

(Some moron overtook both us and the bike at once when we were still behind the bike - and in the face of oncoming traffic. When I was driving later, a van overtook me (just about legally) on a hill where there were two lanes going up, his lane just running out, and a car overtook the van at the same time, crossing 2x solid white lines into a single carriageway coming the other way at the top of a blind hill in order to do it. (I was doing just under the speed limit at the time.) I stayed behind both of them for many miles until they turned off, so nobody gained anything out of the overtaking, as usual. I'd say all that was fairly typical driving these days.)

[rmurphy195]

Flashing or not, there's a new breed of super bright cheap LED lights that are positively dangerous. Twice now on unlit paths I've had to stop because I can't see where I'm going after being blinded by oncoming cyclists and even on lit roads they can be uncomfortably bright.
...
.

This is my experience also. My commute has about 4 miles of unlit canal and river paths. At this time of year I am regularly dazzled by oncoming cyclists with very bright lights. I assumed they are either cheap lights and are spraying light all over the place or poorly setup.

Ditto. Daft if you ask me - how does dazzling oncoming riders/drivers improve road safety?