Just chatting to one of my mates earlier who is (like me) a regular commuter on a bike. On his way home last night someone was drafting behind him with a bright flashing front light, and he found it incredibly distracting (couldn’t see the potholes, etc.) and wondered why anyone would have one. I’ve always wondered why people have them too, but I assume some people on here must use them.

So, why?

Flashing helps you ‘to be seen’ by the oncoming traffic.

Normal lights help with ‘you seeing’ what is front of you and can help others see you.

makes them stand out from other (brighter) lights behind them

One man’s distracting is anothers ‘highly visible’

I use one in conjunction with a steady light (dynamo). They are all about being seen, not seeing.

There are many arguments about the relative visibility and ability of drivers to judge distance and approach speed of flashing vs steady lights, but using both at least gives the best chance of either one doing the trick.

I use one flashing, one steady so that i can be seen and then provide a reference point for anyone in front. Predominantly for people wishing to move into the lane in front of me

I don’t understand anyone commuting with really bright front lights like you’d go MTB night riding with, especially angled into oncoming traffic as they just blind people momentarily.

makes them stand out from other (brighter) lights behind them

One man’s distracting is anothers ‘highly visible’

+1

A slow(ish, relative to a car) moving bike with a steady light blends into the background, especially when coming almost head on like when a driver is waiting to pull out of a T-junction and looking right into the traffic, a pulsing light to most people is really obviously a bike.

Flashing helps you ‘to be seen’ by the oncoming traffic.

Only if it’s quick. If it’s a slow strobe it just a) **** people’s vision up and b) prevents them from tracking you as a moving object. Bad idea, front or rear.

Fast flickering for visibility, or one flash one steady.

A low power flasher can help make you stand out but anyone using an uber bright MTB light in this mode on the road is just a selfish dick. Unfortunately there are a few of them around. Still not quite as bad as those that use them on a separate cyclepath, though.

They do help you stand out from other traffic. I had a (very amiable) conversation whilst queuing one day with a driver of a pickup who asked why I *didn’t* have a flashing front light as although he’d passed me not long before when he looked in his mirror he struggled to see me even though he knew I was there. I was running a B&M dynamo light at the time.

Something subtle that just gets attention is fine, you don’t need the Eddystone Lighthouse 😀

I use a front flashing LED because i think it’s more Visible to Drivers of Cars Who are more interested in Texting, Phoning, and updating Facebook Than looking out for other road users.

I personally feel the flashing also warns “Danger” in the odd occurence where a car goes for an overtake coming towards they often see it, hang back and then go once past.

That must have been one hell of a flashing light though to obscure potholes and also drown out the light on the front of your mates Bike,

That must have been one hell of a flashing light though to obscure potholes and also drown out the light on the front of your mates Bike,

Lots of people out there with them. I’ve had to pull over a few time to let people past. Incredibly distracting and somewhat dangerous for other road users. Should be treated like a main beam on cars and only used where appropriate and turned off at other times.

Still not quite as bad as those that use them on a separate cyclepath, though.

This does my head in. There’s someone on my commute who has a gazillion lumens on his bars and the same on his helmet. Both seem aimed directly into my eyes when we pass rendering my functionally blind for several seconds afterwards.

Front flashing is brilliant for filtering up traffic jams (inside or outside)*. The beam bounces off roadsigns, the reflective stripes of trucks etc, it instantly shouts “cyclists” and you can see cars pull over, knowing that you’re coming up behind them. Minimises left-hook or right-hook incidents.

*yes, I know you shouldn’t filter up the inside but that’s where the cycle lanes are so that’s where some cyclists ride…

However they only really work in urban areas, if you try riding with a front flashing on unlit roads it’s incredibly annoying.

yes, I know you shouldn’t filter up the inside

Allowed in the HC isn’t it? Filter where safe?

front flashing on unlit roads it’s incredibly annoying.

I used to cross paths with a guy on a pitch black singletrack country lane who had a magicsuperfireshine chinese lightcannon on super-fast strobe mode. It used to make me feel sick as we rode towards each other, I’ve no idea how he could ride like that.

I think a bright steady light and a flasher (once or twice per second, my Lezyne Powerdrive is just a little slower than I’d like) with a spread out beam for ‘being seen’ visibility is the best mix.

I find you notice them straight away, and also identify them as a cyclist

I have a front light on pulse all the time

At night I have a helmet light on solid, in the day I put it on fastish flash. Helmet light has a rear that always flashes when on

Daytime I have a rear light on flash, night time its on solid. Sometimes pub a 3rd light on flash on the rear too (Have 4 rear lights in total)

Flashing light seems valuable to me if not too bright, but there’s a point where it becomes horribly disorientating for anyone traveling in the opposite direction.

I know some on here say they want to be seen and screw everyone else, but I don’t think its a good idea to effectively blind people piloting vehicles towards you.

What if there’s another cyclist in their carriageway with lower lights, for example?

Front I have one steady light that lets me see and also be seen plus a low power light on flash mode to help with being seen.
At the back I have one steady and one flashing light, same reasons but also there’s redundancy in case the battery in either runs out or fails – I’m unlikely to notice that happening when actually riding.

Both rear lights and the front flashing light are USB rechargable so they get charged at work before heading home.

I think they’re fine on the road but on a dark foot/cyclepath I find them very blinding when they are coming the other way, it’s quite hard to see pedestrians that you know were between you and the flashing bike light, as you get closer. There’s someone on my regular commute with one, they also stubbornly sit in the middle of the path, it is wide enough for others to pass too, but it’s a bit odd, I suspect they are an angry head-camera type person.

Ive seen more cars turn in front of cyclists with flashing lights than ive ever had with my solid front light.

We know drivers use the most fleeting of glances as confirmation they have fully checked its safe to move, so with a flashing light your presence can easily be missed in that milli-second glance.

However its pretty clear that a flashing light can attract attention when a driver is looking, for example solid lights can be ‘lost’ in amongst lots of other dazzling lights on roundabouts, so a combination of lights is the best solution.

I used a solid front dynamo light for a few years and the only issues I had were at roundabouts trying to turn right. I now have a flashing light on my helmet to help in this situation, however I still progress with caution and presume ive not been seen.

Seriously. You can’t see potholes because of a flashing light behind you? Should’ve gone you know where perhaps.

I only set my front light flashing when it’s really bad visibility – fog, heavy rain etc.

As for the back light, I’ve noticed as a driver that flashing lights are much more noticeable but hard to focus on clearly, whereas a steady light is easier for judging distance and speed. Which is why I have one of each on the back…

Flashing lights first became popular because batteries weren’t so good & they extend run time. Today it’s not so important. I find running solid lights front & rear other road users think you are a motorised vehicle & treat you as such, that is they wait at junctions & give you space. Try it. Flashing lights marks you out as a cyclist, and other road users _hate_ cyclists, or at best habitually ignore. Probably the most visible is the steady & pulse (some lights do both at the same time) but it doesn’t account for the psychology of today’s petrol powered idiot.

I was flashed by a gentleman this morning on my way to work. His front light was so bright I was watching for the aircraft landing. My retinas are still burnt. So I flashed him back with my high beams, seemed only fair.

i got pulled over by the police once using the flash mode on my bike. it was around 8.30am. to my surprise the officers were impressed by the light and commented on how visible i was. they said they could see me approaching them over half a mile away. i asked about using this mode at night and they said it should be fine as it helps drivers identify me as a cyclist and not a motorbike or car with one working light.
even though they said its fine i still use the constant beam when out at night but i make sure i have other lights on the bars and helmet that are on flash mode.
my main light is a c&b seen 1200 lumen unit and the flash mode is very bright and fast. stare at it for more than 5 seconds will leave you either seeing stars, frothing at the mouth in a convulsive fit or blind!

Reflective top, then shine a low light (or two) on yourself. Blinding drivers isn’t sensible

flashing fronts are the bane of my winter commute. i dont know if i just have sensitive eyes but some almost hurt.

a small flashing light is sufficient. a full on nuclear holocaust strobe light is just dangerous and blinds oncoming traffic. you can have a bright, i need to see light, but aim it down a bit and not in my face – thanks!

flash mode on a 1200 lumen light doesn’t seem sensible to be honest, though I suspect it’ll flash lower than that

I really do think a pulsing light is the best of both, it draws attention but it’s not blinding and you can still gauge distance

they said they could see me approaching them over half a mile away

That’s not very useful though, since that’s not when they might hit you.

That super bright light when it’s infront of you can be problematic. Do you people not encounter any other cyclists on your commutes then or what?

I encounter quite a few. Their lighting ranges from none to “can I have my eyes back please”. Most are fine, those with strobe type lights are fairly low power.

Maybe it’s another regional thing.

I like a flashing light personally but I dan’t really understand those flashing lights that are making the sort of light you’d use to actually ride by- it’s contradictory, the power knackers your own vision never mind anyone else’s. You want a flashing light to mostly light the light rather than the world imo.

flash mode on a 1200 lumen light doesn’t seem sensible to be honest, though I suspect it’ll flash lower than that

you’re right its closer to 50% of the total output but the speed intensity of the flash is OTT for night time. in daylight hours i point it a bit downwards so it reduces the likelihood of glaring oncoming drivers

DX are now doing a great wee flashing front light with 3 LEDs in a 4cm disc shape, a chunky rubber band, micro USB and Li-ion battery, for about £7 delivered. Works great in its quick flash mode, not so bright as to dazzle and annoy but plenty bright enough to send reflections from roadsigns at 100m at dusk. I’d say this is a good get you seen compromise run alongside your ‘proper’ commuting light. Runs for several hours in flash mode.

I have to say on the very rare occasion that I drive I find high frequency flashing lights infuriatingly distracting. It’s like I can’t take my eyes off them, which I suppose implies that it makes the cyclist very visible, but I think the fact that they’re so distracting probably outweighs the benefit. It’s pretty much the only “cyclist behaviour” that irritates me and that I see regularly

Flashing (knog blinder 4) says cyclist and steady (Joystick angled down) allows me to see the road properly.

Flashing extends the long battery life, so I ride with the Knog on left-right slow flash during daylight hours. I always have two rear lights, one flashing and one steady. In daylight I use just a flashing light, which is the Fly 6 safety camera.

I’m not going to give anyone any excuses.

That’s not very useful though, since that’s not when they might hit you.

I’d say it’s exactly what you want, to stop someone starting to overtake. I’m impressed with roadies running pulsing front lights in daylight, they’re very effective and let you know there is a cyclist there from a big distance, and I’m sure it stops audi drivers overtaking at them. Most of them seem to wear black and have no lights though, presumably because it sucks being a roadie.

Rather than running a flashing light, you’re better off running 3 lights (as you see on some motorcycles), IMO.

Reasons?

Because of the way the brain works – it tries to make recognisable patterns and shapes out of what the eyes send it, before it even begins processing the information. Anything that doesn’t make a complete shape tends to be ignored, or joined up with something else to make a familiar shape, before the brain sends it to conscious processing.

Single lights thus run the risk of being combined with other light sources (like following cars, reflections or even distant streetlights, etc) before processing, leading to car drivers saying things like “I was looking, but I just didn’t see them”.

But a three-light system makes a complete image – a “face” – and so stands immediately to the scanning eye, causing it to send it to the brain for processing as a unit rather than as a part of something else.

I believe there is something to do with the concepts of closure and gestalt theory in all this if you want to Google it for more learned references, but I’m not sure.

It’s my belief (personal opinion from introspection and self-analysis while driving) that a single, flashing light, only messes with drivers’ eye/brain processing even more, as others here have said.

That’s what I reckon, anyway.

One big light on the bars/stem, and a smaller LED on each fork blade or on your bar ends, maybe … (in the absence of engine bars like where m’bikers put theirs) .. that would make you much more visible than a flashing light that tired drivers can’t really focus on or process as quickly (cos of strobing).

… but I’ve never tested my theories.

I can understand the need for powerful flashing lights front and rear, particularly in London, but most riders commuting through richmond park leave them on FULL BLAST, there are no street lights and enough light pollution reflecting off the clouds most nights so you can ride without lights on full.

Just a minor irritation of mine. Carry on.

Actually London is where it’s worst imo Sonor, far more than a minor irritation. Try cycling up Consitution Hill and then into Hyde Park. I can’t see a bloody thing there some nights, just a mess of strobes. It’s dangerous and unhelpful, and people need to think about what they are doing. Especially those who put their Leyzine micro-drive on blinking daylight mode at night. FFS – I had to pull over.