Running lights during the day

andyeb

Recently I've kind of got in the habit of running lights on my bike even during the day, as I just seem to have fewer near misses with cars with lights on. Does anyone else do this, or am I off my rocker?

An increasing number of newer cars these days seem to come with bright day light running lights - should we all follow suit?

P_Tucker

I suspect you've just done the high horse industry a massive favour with this post, but my tuppence is that if it's safe and you don't get your collar felt by the police then why not?

thescouselander

I'm not totally convinced on this. I think perhaps it's a good idea in dull conditions but in brighter conditions you can actually make yourself less visible if your front light is bright enough and the sun is behind you.

Some lights are designed to be run in the day - my cateye rear light has a daytime mode.

ilm_zero7

now it is law for cars, its only a matter of time before cyclist have to have them I suspect - indeed isnt John Griffin already campaigning that they should?

ShutUpLegs

Excellent idea, and I think we should all get dynamo lights.

thistle_

My feeling is that it doesn't make any difference - I don't seem to have any fewer near misses with lights or without.

Many vehicles choose to pass very close or cut in front of me, but they have seen me without my lights on otherwise they would have run in the back of me.

If someone's going to see you they will, if they're not paying attention or not looking where they are going they won't see you if you have lights on. It's amazing how many people ride at night on unlilt lanes around here with no lights on and don't get run over.

I'm sure there's some scientific research that suggests I'm wrong...

I would be interested to see if road accidents have reduced at the same or a faster rate since daytime running lights were made mandatory for cars.

hodge68

I do, i dont know how much it helps, if at all, but anything that improves my chances is a good thing.

MattC59

P_Tucker wrote:

I suspect you've just done the high horse industry a massive favour with this post, but my tuppence is that if it's safe and you don't get your collar felt by the police then why not?

I suspect that you've misunderstood the OP.

ShutUpLegs

I suspect the person least likely to be knocked off their bicycle is a Policeman in uniform

springtide9

I would guess pointless.

You need a shed load of watts to overpower daylight... not something that a small battery powered light is going to put out.

It makes sense on cars and motorbikes as they are probably putting out 100 watts. To compare, I would guess a really good light is maybe 5 watts (front) / 1 watt (rear)

If want to get seen, wear something brightly coloured; and try to make eye contact with drivers when making potentially dangerous manoeuvres.

alihisgreat

springtide9 wrote:

I would guess pointless.

You need a shed load of watts to overpower daylight... not something that a small battery powered light is going to put out.

It makes sense on cars and motorbikes as they are probably putting out 100 watts. To compare, I would guess a really good light is maybe 5 watts (front) / 1 watt (rear)

If want to get seen, wear something brightly coloured; and try to make eye contact with drivers when making potentially dangerous manoeuvres.

Yellow is the colour that human eyes pick up the quickest.

rolf_f

I've never, ever seen a cyclist in daytime, with lights on, where I noticed the lights until long after I'd already seen the cyclist.

Mind you, with cateyes I could often say the same about some cylists at night

brettjmcc

ILM Zero7 wrote:

now it is law for cars, its only a matter of time before cyclist have to have them I suspect - indeed isnt John Griffin already campaigning that they should?

It's only on the front, rear DRLs are not mandatory yet.

I personally always run a small LED light on the rear that is in blinking mode. To ALIHISGREAT's point, the human eye also naturally picks up movement, hence you will tend to notice blinking more than a solid light.

Bobbinogs

In bright sunshine I don't bother...but for the other 364 days in the year I always have f/r set on blinking mode (uses very little power and the batteries are rechargeable anyway). OK, may not do much good but if it ever saves my skin just the once then it was all worthwhile.

I still think that the best way to avoid a spill is to develop a keen spidersense though. I am getting a lot better at predicting those cars that are going to pull out on me irrespective of lights, clothing, road position. The advanced driver training that my company made me do probably helps in this aspect, although much of the training reminded me of that H&S nerd on telly who fretted about everything, even bamboo sticks in his garden ("garden is an anogram of danger"), heh heh.

springtide9

At what distance are you expecting to see the blinking? Maybe 10 ft?

On an Overcast day, the sun gives off roughly 1,000 lux. On a bright day it's 10,000–25,000 lux
http://en.wikipedia.org/wiki/Lux

And to compare to bike lights: http://reviews.mtbr.com/lights-shootout ... asurements

A 250 Lumens light will produce approx 20 LUX at 5 feet. As you double the distance, you half the power. So at maybe 40 feet, you'll have maybe 1 LUX.

So if you want to be seen in the day you are better off reflecting that big light source in the sky rather than trying to overpower it with a tiny LED bulb (even if it's flashing!). In reality, there will be more light given off from the reflector on the light (reflecting the Sun) than coming from the LED.

brettjmcc

It's just a small Cateye Loop rear light. I am under no illusion that it does not give off much but is there as a backup that goes on the back of my saddle bag. It's there just as an indicator, nothing more, like I said your eye will naturally be drawn to something flashing/moving.

The fact I wear bright green Liquigas team kit is probably provides more of a visible indicator than anything else (oh no, I just mentioned I wear team kit....)

bails87

Totally anecdotal, but I find I get more cars pulling over to let me through when filtering when I've got my Smart 25 Lux light on flashing mode (in daylight) than when I don't.

I think the flashing helps to grab attention, so they look in their mirrors and see me.

There's a guy who rides in the opposite direction to me with a front light with a 'pulse' mode which makes it go bright-brighter-bright, rather than off-on-off. Possibly an Exposure? In any case, I can see that from a distance of at least a KM away on a long straight road, even in the bright sunshine that we've had lately.

Is his light brighter than the actual sun? No, of course not.
Does that render it pointless? Definitely not.