Are daytime bike lights a safety essential? Should you get daytime lights?

Most collisions occur as drivers don't look, either long enough or at all.
This is bullshit from a company that makes and sells lights and wants to sell more.

Where is the evidence that daytime lights save cyclists lives?

My commuter bike has hub dynamo lighting, and I leave it on all the time. The front light probably doesn't make much difference in daylight, but I like having the rear light set to always on; that way when it gets cloudy or you go under a bridge, you've got that extra 'notice me' element. I agree with Gazza that the main problem is drivers not looking, but having the option of daytime running lights is one that I appreciate.

I wouldn't like this to become mandatory,

but I think its a good idea.

I personally notice other cyclists from farther away when they have lights on, even during the day.

I have no evidence to back up this opinion.

I have lights on all the time. One less excuse for other road users not to see me.

I keep my rear light fitted during the day, so its there if I need it - but should the lights be on as a rule during the day?

NO

The biggest issue is run -time. In order to be useful the lights will been to be very bright, which means that run times will be at a premium. How many will last an 8 hour ride?
Does not make sense to me to have the light on all day, only for it to run out of juice just as the evening gloom is starting to set in.

However it is sensible to switch on the lights an hour or two before sunset - when the sun is low it can make visibility difficult, and anything we can do to stand out in front of a glaring sun is worthwhile. Similarly worth having the light on during rain and mist etc

there's a full review of the Flare R coming, but for the record here are the things i like about it:

1) it has two sensible steady modes for night and group riding
2) it has two pretty brutal flashing modes that are genuinely visible in the daytime from a really long way away
3) it comes with a good mount and a neat clip for clothes or the back of a bag
4) it's nicely made

and does it make a difference in the daytime? well, anecdotally it seems to, yes. you still get crap, impatient passes from people that have seen you but just can't be bothered to give you decent space. but overall, there are fewer bad passes. i'm not claiming this as a scientific proof, it's simply my experience of using the light over a couple of months. your mileage may vary, etc and so on.

I ride with lights 100% of the time, except today, as I forgot to grab them from charging

run time: i mostly use it in night flash mode which, incidentally, isn't a mode i'd use at night because the flash is too bright. stated run time for that is 23hrs. day flash mode run time is stated at 5.75hrs, so not ideal for longer rides

I find myself leaving my front light on flashing mode in more daylight hours these days mostly because of the 'sun dappled' country lanes. You can go from bright sunshine into, what for the eyes is, relative darkness, leaving your vision temporarily impaired. In an instance like that for a car coming the other way, having the front flasher on could make the difference between being seen or not.

As for the rear, I've got a Fly6 now which is always recording, so there's always a light on there anyway, but I guess the same thing applies.

Ultimately I can't see that it can harm (except your wallet) to have a bright rear light during the day. I don't think it should be mandatory (ditto helmets, high-vis/YJA, reflective clothing), but I think it is more than somewhat cynical to believe Trek are only doing this to line their own pockets (after all they're hardly a monopoly, indeed Bontrager isn't the first brand I'd think of with respect to bike lights).

I leave my lights on all the time. As they are dynamo lights it's just easier. My rear light also gets brighter when I brake, which is nice.

cant see it making a massive difference though. Just another way of victim blaming.

In tree lined country lanes on sunny days visibility is a real problem- I nearly always have at least a rear light on. It is a bit like helmets- I don't see that it can do any harm, and it might help.

But, as with helmets, it must be the individual's choice/ responsibility.

I agree. Think about those times you've been driving with the sun ahead, bouncing off your dashboard and making it difficult to see. You slow down a bit but the tall hedgerow to the left is no longer green, it's black and completely in the shade. Pedestrians and cyclists can easily be masked by that shade. Not all drivers will slow down, so I keep out of the shade but I also use my rear light (hope district) to reduce the chance of being hit.

Absolutely NOT!
Drivers need to learn to drive properly, more stringent tests.
Driving is a privilege and not a right (or money making scheme).

This "only doing it to line their own pockets" argument has never made sense to me.

Tesco don't sell me food out of the goodness of their hearts. Doesn't mean I shouldn't eat.

I've always ridden in daylight hours with a rear light. Personal choice I know and (without waking the victim-blaming evangelists) having been cut across and hospitalised on my motorbike resulting in ruptured artery and lots of internal bleeding and a written off bike, I choose to use anything that might wake up a dozy or distracted driver to my presence.
My rear light of choice is the Niterider Cherry Bomb, which has a half mile visibility and was reasonably priced. The bracket is crap though and needed a little modding.
A few quid on batteries each year, why would you not?

Totally agree I ride with my See.Sense lights on all the time.
The problem I had with other lights in the past was they are just not bright enough to be seen during the day.

Anything under 70 Lumen will not be bright enough to be seen on a bright sunny day.
Also the way the light is dispersed is very important they need to have great side visibility.

I see the problem of cyclists not being seen on the road getting worse over the next 10 years.

A few years ago a euro law made daytime running lights on vehicles mandatory. Now drivers are used to seeing bright LED's when there is something in the road. Over time proportion of cars on the roads with daytime running lights is going to get higher and higher. This will make drivers eyes lazy, only looking for a bright light in the road lane.

I suspect it is only a matter of time for LED's front and rear to be built in to bike frames/ handlebars and powered from the electronic groupset or frame battery (for cable groupsets). The technology is already available, it just needs one leading brand to decide to do it.

Personally i don't use lights in the day, but make sure i have them for evening rides when there is a chance of being out at dusk.

I’m sensing that most of the comments are from sports cyclists who are more likely to be mixing with fast moving traffic on busy roads. On a 70mph dual carriageway in poor visibility a rear light seems a sensible choice (although I would resist it becoming mandatory).

For your typical utility cyclist pootling about town or a leisure cyclist out on a quiet run in the country it’s not necessary. Yet another reason for people to be put off riding a bike.

Look at any video of Dutch people riding bikes during the daytime. Not a red light in sight. See for example: https://www.youtube.com/watch?v=Jpi01x_DgDY

I ALWAYS have a flashing red on the go.
The human brain is hardwired to respond to changes in stimuli as a priority & de-prioritise stable state information. Whether consciously or sub-consciously, another road user will be more aware of you with a flashing tail light.
My commute used to be partly along leafy lanes and (even more so on a bright, sunny day) a car driver driving into shade under trees will suffer several seconds of visual acclimatisation; it's a physiological certainty. They WILL notice a flashing light in the shade of those trees where they might immediately see you otherwise. The earlier another road user notices you, the safer you should be.
Do whatever you can for yourself & stay safe.
I admit, I can be as self-righteous as anyone but I'd rather not do it from a hospital bed.

Realistically this is a sticking plaster solution to dangerous roads. It would be much better to fix our roads and make them safe for all, rather than just try to sell cyclist more stuff.

I have to admit when it gets gloomy and cars have their lights on I tend to put mine on too. It helps to be seen from a very long way off.
I see some riders do the same even when it's bright and sunny, which I think is of no use at all.

Something I noticed this morning, cycling along a cycle path and car coming towards me, then as drivers do it turns across in front of me ( I was a little way from junction so no issue) but it was only at the last minute that I noticed it actually had indicators! The DRLs so effectively masked the indicator! this isn't the first time I have noticed this.

More on topic, If you ride in sunny weather in and out of the cover of trees you can loose sight of things. I can see where a rear light may help, but this comes back to the old CTC argument. Why should bikes have lights, shouldn't the onus be on the driver to look where the f*** they are going? All those drivers complaining about not cyclists not having lights? If not having lights means you can't see them how do you know they are there, or is the issue that the drivers don't have hours to respond, that they aren't actually paying attention and are simply victim blaming to cover their own crap driving.

http://www.bontrager.com/features/flare_r

I don't know if the image is on a carrousel I don't think so, just in case, the image of a car driver using a phone following a cyclist, now shall we change the image to a hooded man following a young woman in a short skirt. Where would you put the effort to solve the problem?

Road bike has a SP dyno-hub and Exposure Revo/Redeye lioghts on. For commuting, they're on all the time. For epic multi-day rides, they're off in the day as GPS-charging takes priority. I'm not going to fit other lights for those situations.

As ever, its cyclist's choice. Yes, drivers need to be more aware, but it only takes one who isn't to crush you to death, so what harm can it take to prevent that one from missing seeing you?

As many above have said, speaking from experience driving my car, you can strike situations where combinations of sun angle, shade, and other factors combine to temporarily blind you. You can't always anticipate these, and in the time it takes to react you've gone 50+ yards.

*anything* that increases your visibility is A Good Thing. Making it mandatory, not so much.

No.
It transfers responsibility even further from the looker to the lookee.

I agree with the CTC's original position and reasoning when they actively campaigned against compulsory lights on cycles during the hours of darkness. At the time a cycle was only expected to have reflectors.

Why am I at 6'2" perfectly visible to motorists until I throw a leg over a cycle?

Yes I do use lights during the hours of darkness and times of reduced visibility. If there was less light pollution then cycle lights and reflectors would be more effective.

Have daytime running lights delivered the promised reduction in accidents?

I run into a bit of the old dissonance here.

On the one hand, for numerous reasons I completely resist the notion that bicycles should essentially become cars:
http://singletrackworld.com/columns/2015/02/bez-the-wedge/

But on the other, I use a rear light most of the time. In fact, the overwhelming majority of my riding is done with dyno lighting which I leave it on all the time (front and rear).

There are a few reasons I use a rear light a lot:
- I never have to make a decision about when the conditions have deteriorated enough to warrant turning it on.
- If conditions suddenly deteriorate, such as going under full or dappled tree cover on a bright day, it's already on.
- I think I get fewer close passes when using a rear light (but this is hard to be objective about).

It's a pragmatic thing. I'm absolutely against the idea that people should be responsible for being seen, at the expense of the idea that people should avoid driving vehicles into things they failed to see, but equally I don't want to get hit.

Lights are one of the few things that, to my mind, do make a difference and don't unduly encumber me; unlike, say, hi-viz clothing. And I'm far more at ease with reasonable adaptations of the vehicle than I am with forcing the user to dress in a certain way.

Devil's advocate argument: "Making daytime lighting a legal requirement would trigger a sea change in bicycle lighting in the UK. You'd see more use of dynos, more bicycles sold with lighting, and fewer unlit bicycles at night." Discuss

The image that mrmo pointed out, though— http://www.bontrager.com/features/flare_r —can go and blow a goat. I think that's a pretty nasty piece of advertising.

This should not be mandatory. But:

I always race TT with the rear flasher on.

I commute with powerful front and rear lights both set to strobe. Just to make doubly sure in traffic that I've made myself as visible as possible. Of course this will only really matter around drivers who were looking, but might have otherwise missed me in the grey blur of the world.

I think it's especially useful if it's raining though, visibility from a vehicle does suffer there, so making yourself stand out like a flashing Christmas tree might just save you.

It won't help me against the fecking ejits who don't care about my safety, but it might at least go some way to resolve myself of any contrib if I get taken out and their insurance tries to lay some blame on me.

It's a bit like the helmet debate. But lets not go there.