Daytime Running Light Study
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I found a study that matches the description in the video
https://www.sciencedirect.com/scienc...606?via%3Dihub
The full study is behind a paywall.
https://www.sciencedirect.com/scienc...606?via%3Dihub
The full study is behind a paywall.
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Thread moved from Electronics to A&S.
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I found a study that matches the description in the video
https://www.sciencedirect.com/scienc...606?via%3Dihub
The full study is behind a paywall.
https://www.sciencedirect.com/scienc...606?via%3Dihub
The full study is behind a paywall.
EDIT: I found it for you. I got the Unpaywall extension, and it took me straight to the PDF file.
https://vbn.aau.dk/ws/portalfiles/po...r_bicycles.pdf
Last edited by JW Fas; 10-15-23 at 12:34 PM.
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You can't be TOO seen!
I go a tad overkill on the daytime lighting. Front and rear. I dial it back after dark.
I'm happy someone did a real study but I didn't need convincing that the sooner a motorist notices me the better.
I go a tad overkill on the daytime lighting. Front and rear. I dial it back after dark.
I'm happy someone did a real study but I didn't need convincing that the sooner a motorist notices me the better.
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I have dyno lights on 2 bikes now, always on and NOT blinking.
Riding on highways with hundreds of 22 wheelers half the time. NOBODY doesn't see me from a quarter mile back.
Could be the lights, clothes, bags, fenders or me sitting up most of the time. 99% give me all the extra room available in the situation. Then there's lots of times I'm the one who has to give the extra room. That's why my mirror is enormously useful.
Riding on highways with hundreds of 22 wheelers half the time. NOBODY doesn't see me from a quarter mile back.
Could be the lights, clothes, bags, fenders or me sitting up most of the time. 99% give me all the extra room available in the situation. Then there's lots of times I'm the one who has to give the extra room. That's why my mirror is enormously useful.
Last edited by GamblerGORD53; 10-14-23 at 10:35 PM.
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I agree and when I’m driving I always spot cyclists earlier with powerful day lights, especially flashing lights. So they are a no-brainer for me.
Last edited by PeteHski; 10-15-23 at 10:55 AM.
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Yes to lights! I ride about 3,000 miles a year on NYC streets, sharing the road with the our city's cautious and caring drivers. Oh heck yes to lights.
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In fact, you can, as many first responders are slowly learning. Excessively bright and/or poorly-aimed lights blind other road users, and blinded road users cannot see you. The recent trend of equipping police and emergency vehicles with billion-candle-power LEDs seemed like a good idea, but is resulting in just as many impacts and fatalities because -- to no one's surprise who has considered the matter -- indiscriminately blinding drivers does not improve anyone's safety.
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Not long ago I was driving down Austin Texas. Saw what appeared to be a cutie with long hair slowly ridding a step through wearing a pink tutu and a tank top. As I passed I noted his long black beard.
Yep... wish I had not seen that one...
Yep... wish I had not seen that one...
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In fact, you can, as many first responders are slowly learning. Excessively bright and/or poorly-aimed lights blind other road users, and blinded road users cannot see you. The recent trend of equipping police and emergency vehicles with billion-candle-power LEDs seemed like a good idea, but is resulting in just as many impacts and fatalities because -- to no one's surprise who has considered the matter -- indiscriminately blinding drivers does not improve anyone's safety.
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Night/Day ... Flash/Steady ... I see a lot of worry about the wrong things. In the thumbnail above the rider is to the right of the fogstripe on one of the most beautiful (if narrow) shoulders I've ever seen. I'd be on that in a New York second! First Responder vehicles get hit because they are in traffic. That, and often when stopped they don't fully pull out of the path of traffic. Hint. Don't be in the path of traffic. Nothing else you can do matters.
You think its your bright, steady, daytime (and night) lights saving you? I don't run lights in the day, and I run only one f/r, tops, at night. Why am I still alive? I think it's because I don't ride into intersections without knowing that they are clear, and I stay OUT of the main flow of traffic unless my way forward is blocked. I have ZERO fear of entering the right hand lane or even the lane to the left of that, if necessary. I don't HANG OUT over there, but I am able to be there if that is what it takes.
I don't get freaked or even annoyed, if something is parked in the bike lane because for the few seconds it takes to go around them, it I hardly feel like I am in any danger. It's not your lights. Mostly its that no one really wants to kill you. But they can if you are in their way. Stay out of their way.
TL;DR: You actually don't need lights at all to be very safe out there. But if you are ever nailed and you don't have any you will be clobbered financially and may wish you didn't survive. So run the legal minimum of lighting equipment and call it very good. The rest is down to common (road) sense.
You think its your bright, steady, daytime (and night) lights saving you? I don't run lights in the day, and I run only one f/r, tops, at night. Why am I still alive? I think it's because I don't ride into intersections without knowing that they are clear, and I stay OUT of the main flow of traffic unless my way forward is blocked. I have ZERO fear of entering the right hand lane or even the lane to the left of that, if necessary. I don't HANG OUT over there, but I am able to be there if that is what it takes.
I don't get freaked or even annoyed, if something is parked in the bike lane because for the few seconds it takes to go around them, it I hardly feel like I am in any danger. It's not your lights. Mostly its that no one really wants to kill you. But they can if you are in their way. Stay out of their way.
TL;DR: You actually don't need lights at all to be very safe out there. But if you are ever nailed and you don't have any you will be clobbered financially and may wish you didn't survive. So run the legal minimum of lighting equipment and call it very good. The rest is down to common (road) sense.
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A daily occurrence in NOLA, especially near the French Quarter.
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As a driver, I prefer seeing cyclists from a distance and good lights ensure this. Hard to see how anyone could rationally argue against this.
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The most important safety device is between our ears. Everything else should be considered an added layer of safety. When we add layers to enhance daytime visual conspicuity, we aren't trying to catch the attention of an engaged motorist. An alert motorist will see us. We are trying to steal the attention of the marginally engaged. To that end, the more layers the better.
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Motorcycles didn't always have lights. They have them now and they run them day and night. When someone is looking ahead in traffic they are looking for things that can interfere with there travel. They easily Se larger objects like cars and trucks. This is what they expect to see and there brains are accustomed to this. Motorcycles, bicyclists and pedestrians are often missed when they are scanning the road. What gets people's attention, when they are driving there automobiles, is bright lights and movement. Noise can also work if the motorists is not playing there radio to loud and the emergency vehicle is close enough. There have been plenty of studies on this to prove lights are effective. When I started bicycling in the mid seventies I rarely had close calls with motorists passing to close. It has become all to common since then. I purchased my first tail flasher near 7 years ago. It had an immediate effect. Some People have better things to do while driving than drive. You can't always watch your back. Lights help with this problem.
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I have noticed many more riders wearing Bright Yellow Reflective Vests in the day time with or without lights on.
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IMO there's no rational debate against daytime lights, especially a bright, daylight visible red strobe in back. I stress the rear because I have some degree of control over potential hazards coming from front and side, but am 100% passively dependent on drivers behind me seeing me.
That said, I wonder whether we may be overselling the added safety lights may offer, and thereby depreciating other important safety considerations. IMO situational awareness and learning to "read" traffic are probably more important, and hope that cyclists who buy lights do not fool themselves into believing that just being visible is enough.
That said, I wonder whether we may be overselling the added safety lights may offer, and thereby depreciating other important safety considerations. IMO situational awareness and learning to "read" traffic are probably more important, and hope that cyclists who buy lights do not fool themselves into believing that just being visible is enough.
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The data is very clear that your claim is incorrect.
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Running lights at night is a no-brainer. My commute starts at 6 am, and at this time of year I've seen a few cyclist on the road without any kind of lights, but only when they are up real close to me. A few occasions they were riding on the wrong side of the road, and once they are into my field of light, it always comes as a shock. WTF! WRONG SIDE!!! GET SOME LIGHTS!
Daytime lights? Debatable whether they help. Nevertheless, I run them.
Daytime lights? Debatable whether they help. Nevertheless, I run them.
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The data is very clear that your claim is incorrect.
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In fact, you can, as many first responders are slowly learning. Excessively bright and/or poorly-aimed lights blind other road users, and blinded road users cannot see you. The recent trend of equipping police and emergency vehicles with billion-candle-power LEDs seemed like a good idea, but is resulting in just as many impacts and fatalities because -- to no one's surprise who has considered the matter -- indiscriminately blinding drivers does not improve anyone's safety.
Yes, emergency strobes can and do endanger workers in the shadows. The bright light reduces visibility the same way a bright light source will darken the background in a photograph.
Likewise, a bright rear strobe will endanger you IF you dismount and walk forward and to the side of your bike.
However, no one would or could be in his own light's shadow while riding.
That said, I join you in arguing against crazy bright strobes. You want to stand out without blinding people.
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I only posted because I felt you were making a false syllogism from the very real issue of roadside workers obscured by high intensity vehicle strobes, and the issues for cyclists.
Also note that the off interval of bike flashers is short, so driver awareness is restored fast enough to ensure safety.
Personally, I'd love to see real data comparing flashing red vs. steady red on bikes.
FWIW eons ago, before NYS changed the law, I used a flashing amber rear. Stopped twice by cops because flashing amber is for stationary hazards. (before amber turn signals on cars in USA) Sent off with good wishes after I explained that I'd rather that drivers thought of me as a hazard and underestimated my speed. Flashing amber bike tail lights are now legal in NYS, though I've never seen any.
In any case this thread is about DAYTIME running lights, and I've yet to see any bright enough to cause shadows.