Daytime lights

[ChrisF]

Cycling on some popular routes in Austria recently (e.g.the Danube cycle path) I noticed how many riders (mainly e-bikes probably) had their front lights on full power in the middle of the day, in bright sunlight. I reckon 50% of the e-bikes were like this.
Why? What a waste of battery life. More importantly, I hope this isn't a sign of things to come, where bikes (like cars) will be forced to have lighting at all times.

[Debs]

Daytime lights on bicycles are a great idea, i use mine all the time now
I would however strongly object to any laws making them compulsory.

I feel the same way about helmets, it's good to have choice, i choose to wear a helmet but strongly don't believe they should be a legal requirement.

[ian s]

I entirely agree; I dislike lights on in broad daylight as well. The number of time I see people riding cycles in dark clothes but with lights on the bike in broad daylight is stupid, the cyclist obviously wants to be seen, but is so ecologically unfriendly as to waste energy emitting light when reflective clothing would do the same for no energy consumption

[tatanab]

What is odd is that people will use very small or very weak lights in daytime. I spot the rider clearly 10s of seconds before I spot that they have a glow worm on the handlebars. Equally odd are those who have lights to rival the sun (ok, I exaggerate) such that if they come behind me when I am driving I have to adjust my mirror or tilt my head away from this hyper power obnoxious flash. I reserve a special place in hell for them along with night riders who have such lights spraying light all over the place including into the face of riders coming the other way.

I dislike the idea of daytime lights (another American escapee) because it could harm the safety of those who do not adopt them. How would I cope with month long tours if such lights became expected?

[alexnharvey]

I entirely agree; I dislike lights on in broad daylight as well. The number of time I see people riding cycles in dark clothes but with lights on the bike in broad daylight is stupid, the cyclist obviously wants to be seen, but is so ecologically unfriendly as to waste energy emitting light when reflective clothing would do the same for no energy consumption

Would reflective clothing make a cyclist more visible in daylight than dark clothing? Your assertion, prove it.

Would this advantage be greater than any benefit from daylight running lights (DRL). Implied by your assertion.

If there is some visibility advantage from DRLs, how would you balance this against the energy consumption?

You know that reflective gear is mostly plastic? how do you sleep at night?

[kwackers]

I entirely agree; I dislike lights on in broad daylight as well. The number of time I see people riding cycles in dark clothes but with lights on the bike in broad daylight is stupid, the cyclist obviously wants to be seen, but is so ecologically unfriendly as to waste energy emitting light when reflective clothing would do the same for no energy consumption

My daytime bicycle lights are dynamo.
Main reason they're on in the day is because I can't be bothered turning them on and off.

I've tried flicking the switch back and forth for some time under all sorts of conditions and if it makes a difference at all I'm buggered if I can feel it.

[mjr]

Yes, daytime lights are up there with H&H as having no significant measurable benefit for cyclist health. This one seems less surprising, though, as the sun is brighter than any bike light, even through some sorts of cloud.

[atlas_shrugged]

Good thread. IMHO there is a huge problem here caused by blind drivers or drivers who are unable to notice. The issue is made worse by shady/sunny roads and sun shining on dirty windscreens and glasses. Add to this an aging population of drivers and also cyclists wearing dark clothing and riding bikes that have a lower frontal area (e.g. recumbents) and SMIDSY is the result. I will start a more broad thread about this after letting this thread run for a bit as I have an interest in this area i.e. self preservation.

[drossall]

It's hard to see how using lights on a bike in daytime could make that immediate ride less safe, so there's a case for saying "Why not?" The problem, it seems to me, is that it encourages a general use of DRLs. That will mean that car lights far overpower bike ones again, and so cycling will become more dangerous. The roads are not a place for a lighting arms race, with everyone saying, "Look at me!" "No, look at me!"

[mjr]

It's hard to see how using lights on a bike in daytime could make that immediate ride less safe, [...]

Two easy to see ways suggested by some:
1. Visibility requires contrast and a light reduces the contrast between cyclist outlines and sunlit backgrounds, breaking up their outline;
2. Lights distract from looking at the whole shape and identifying it as a cyclist.

[pwa]

I will be out on the bike later today, mostly on country lanes, and I will not be riding with lights on. If it were raining or light levels were low it would be a different matter, but it is a bright sunny day and I will be riding on lanes that pedestrians walk, so I expect to be easy to see. A light would just be a token rather than a practical asset in those conditions.

[hemo]

Only use when low light or in poorer vis on the bike.

[pjclinch]

Good thread. IMHO there is a huge problem here caused by blind drivers or drivers who are unable to notice. The issue is made worse by shady/sunny roads and sun shining on dirty windscreens and glasses. Add to this an aging population of drivers and also cyclists wearing dark clothing and riding bikes that have a lower frontal area (e.g. recumbents) and SMIDSY is the result. I will start a more broad thread about this after letting this thread run for a bit as I have an interest in this area i.e. self preservation.

If a driver doesn't look then you're snookered.

At a trainer's course I was on someone regaled how he'd been rear-ended at a roundabout. Of course the rest of us anxiously asked if he'd come out of it broadly okay and he said that of course he did, because he was driving a fire engine at the time. So looking is the key, and if someone looks they'll generally see. Stuff like small frontal area of recumbents is, I strongly suspect, a red-herring. If you're looking you can see potholes, cats, crows, traffic cones etc., all of which give less visual notice of themselves than a 'bent.

(This is all connected to why, whenever reasonably possible, eye contact is a key point in negotiating your space on the road with drivers, though that's a bit of a moot point wondering if the person zooming round the blind bend will see you in time)

Pete.

[mattheus]

Good thread. IMHO there is a huge problem here caused by blind drivers or drivers who are unable to notice. The issue is made worse by shady/sunny roads and sun shining on dirty windscreens and glasses. Add to this an aging population of drivers and also cyclists wearing dark clothing and riding bikes that have a lower frontal area (e.g. recumbents) and SMIDSY is the result. I will start a more broad thread about this after letting this thread run for a bit as I have an interest in this area i.e. self preservation.

If a driver doesn't look then you're snookered.

At a trainer's course I was on someone regaled how he'd been rear-ended at a roundabout. Of course the rest of us anxiously asked if he'd come out of it broadly okay and he said that of course he did, because he was driving a fire engine at the time. So looking is the key, and if someone looks they'll generally see. Stuff like small frontal area of recumbents is, I strongly suspect, a red-herring. If you're looking you can see potholes, cats, crows, traffic cones etc., all of which give less visual notice of themselves than a 'bent.

Pete, your fire-engine story is so great, I hope you keep posting it forever

I would add to the anecdote pile; plenty stories of SMIDSYs to riders lit-up like christmas trees.
(there is a whole web-page somewhere of hi-viz/illuminated objects struck by motor-cars - not by drivers of course.)

[Icsunonove]

Lights in the day time? Whatever next? The world's going mad.