1) I agree (that steady is not better). Bike blinkies are small. There's nothing to triangulate distance with, they're a point-source of light even when running steady. Might as well have them flashing, so they actually get noticed.

2) A good blinkie should be noticable from a great distance in darkness anyway. I spotted a SuperFlash from about 1/2 mile the other day at twilight (could ID it as a SF by its strobe pattern). If it had been running steady, I probably wouldn't have noticed it at nearly that range, however... it's the strobing that catches my eye.


So I always recommend running taillights in flashing mode. They get noticed, and they differentiate you from other sources of red light. Personally, I mentally associate blinkies with humans, primarily cyclists. If you want to provide range info, use multiple lights with physical separation (bar-tip lights, helmet-mounted light, lights on each pannier, etc). Think about how much easier it is to get range on a car with two or three working taillights, versus just one... and that's despite most cars having taillights that are very, very large compared to any bike blinkie. Make sense?


Reality check: cruising the highway with a DiNotte 140 in five-pulse mode, and watching the reactions of overtaking traffic using my helmet mirror... there doesn't seem to be a problem

You can't go wrong with an eighteen inch reflective farm triangle:

Actually, there are 12 volt DOT lights at the bottom corners of this reflective triangle, but the reflection almost totally drowns them out.
I believe my bike is a "Slow Moving Vehicle". I hope I don't stir up a debate with the hard-line VC'ers.

Also in this photo, you can see the amber marker lights on the front basket, and the sealed beam headlight is on.

Of course, if every bike had the required complement of lights, not many people would want to steal them for their own bikes... because, of course, their bike has lights, too.

Not offhand, but it's out there, and I think it's been cited (or at least linked to) on BF in the past.

Motorcyclists have the same concerns, and go the extra step of adding lights to add width, making their speed & distance even easier to determine.

Honda's got a research prototype motorcycle with twin diagonal-shaped headlight assemblies, LED bars on the fork legs, and yet another light on a mast above the rider.

https://world.honda.com/ASV/motorcycle/
Video: https://world.honda.com/HDTV/ASV/ASV-3-motor/index.html (skip to after the 5-minute mark, particularly at 7:00)

I'm surprised to learn that front and rear lights, not only reflectors are not mandatory in every US state.

I usually ride with a steady red light on the rear of the bike (seatpost mounting), and flashing lights attached to my back pack - at the moment there are three of those. I'm told the effect is pretty noticable.

This Jogalite stuff seems to work well. But, I consider a rear reflector to be a "backup" to my planet bike superflash. Yes, it's quite bright and visible. In these "dark times" I also like reflective leg bands.

Massachusetts law is similar to other states' laws: A white headlight, visible for 500 feet, is required. There is no maximum power specified. Does anyone know of any state law that specifies that your headlamp cannot be over a certain power? Oddly enough, a red tail light is not required, but sensible cyclists use one anyway. A red reflector meets MA's requirement. I think most of these state laws were written decades ago, and need to be updated, as lighting technology has changed quite a bit.

Today's cycling lights are great, a vast improvement from what we had 30 years ago.

that's an anecdote too, unless you can show us the statistics of which you speak

I have a feeling that the blinking light ==> inability to judge distance is old conventional wisdom. During the mid-70's there was a line of bike lights sold that had an incandescent bulb and a very low blink rate to conserve the battery. That was when I first heard the blinking rear light ==> difficulty judging distance. For that particular line of lights I can believe that it would be true. The blink rate was very low maybe 0.25-0.5 Hz. The cyclist could move a considerable distance in the off interval. If the rider was rocking the bike while he/she rode it could wreak havoc with some observer trying to connect the dots.

For today's LED based flashers The blink rate is much much faster. I'd be very surprised if a modern blinkie resulted in problems with an observer.

As a fine point most LED based headlights that have several intensity levels ARE blinkies. Modulating the blink rate or blink duty is how they achieve the different levels. So at some blink rate it doesn't matter any more; blinking looks like steady.

I checked the Massachusetts laws. There doesn't seem to be any objection to rear blinkies in them.

Speedo

FWIW, many of today's flashing headlights really aren't any faster. You mention LEDs' low-power modes that are really superfast blinks, but that's a moot point since they appear steady anyway. There are also lights like Niterider's that go bam-bam-bam-bam-bam as fast as you can say it, which I'd never use because they're just too damned annoying (one of my friends has one and I can't stand being near it; I'd hate to be in whatever car that she parks behind at a stoplight).

But, like I said, many flash patterns just aren't crazy fast. As an example, Dinotte's slow on-off is the same frequency as the warning beacons you see in road construction zones. I have a couple Serfas lights that are the same way.

When I see that, I think of a parachute on days with a strong headwind.

The point about the low power headlight modes is that they are only perceived as steady. They are not really steady. It is an objective demonstration that there is a flash rate at which an observer will no longer have difficulty in tracking the light.

The slow flashing headlights are for daytime. At least that's what the instruction book for my Nite Rider says. They're there to get your attention, but in the day time they aren't quite so blinding against the daylight background. I would find them annoying to use at night, and would be very annoyed by somebody coming at me with one flashing at night.

All of the rear blinkies I have blink very fast. I tried to count my now slightly long in the tooth Vistalight and even that was too fast for me to get a good estimate of the flash rate.

I would be interested in seeing any real, as opposed to rumor, evidence that there are safety issues with flashing vs. steady rear lights. For all my lights steady is an option, with the cost being faster battery consumption. Until then I'll keep on flashing.

Speedo

Maybe it is time to learn what the hard-line VC'ers actually advocate.

Which is, that there is not need for AFRAP laws, because whenever a cyclist is moving slower then the speed limit, the "Slow Moving Vehicle" laws are sufficient to cover the situation.

So hotbike, welcome to the hard-line VC'ers camp, you are now a confirmed member.

I've followed cyclists with a single rear flashing light at night, and I have misjudge the distance between us several times when viewed from afar. Personally, I like to run two rear lights, one in steady mode and one in alternating.

Sure, but I've experienced the same thing when viewing a steady light at night without any other cues to let me know the distance. We judge distances (at least those greater than a few feet where binocular vision plays a role) by having an estimate of how large or bright the object is. Lights vary greatly in brightness, so unless we already know this particular light that doesn't help much. And the light by itself is too small to use that to gauge the distance. What does help is if the light is bright and close enough to illuminate parts of the bike enough to be seen - like the seat, rack, or rear wheel. Then we use our knowledge of the size of a normal bike to get a good estimate of the distance. But that's usually only when we are already quite close to the cyclist.

Just seeing an isolated light up ahead of us does not let us make a good estimate of the distance regardless of whether it's flashing or steady. But as long as the light gets noticed, then the following motorist is likely to pay it some more attention as he gets closer. Eventually he'll get some context, such as seeing parts of the cyclist or bike, that allows a good distance estimate.

and that's why the EU countries mostly specify dyno lights, avoid blinkies, and have standards for the number of lumens headlights must generate at certain speeds. In the US, there are no standards and intensity and modulation frequency of different lights is all over the place.

Some years ago when I had a GT I had a nice xenon strobe taillight. Sadly, while I was in Winn Dixie the bike it was on was stolen, as was the trailer that was hooked to the bike to carry my groceries home. Does anyone know if any company is still using a xenon strobe in their taillights?

Here's one: https://www.lightmanstrobes.com/lightman-xenon-strobes

A little late, but on the topic of stuff being stolen off of bikes:

The argument that if everyone had lights, people wouldn't steal them, is bogus. People steal saddles and posts all the time. I always take my headlight and tail light with me when I lock up. The first time my gf parked her bike outside, someone stole her junky Blackburn pump. I do not believe for a second that people won't steal whatever isn't bolted down, which adds weight and decreases convenience. I hope the US never requires dynamo lights; the ones I use, with my reflective tape, are more than sufficient to be seen, and dynamos would only add weight and suck power from my ride. No fun.

Maybe it is the EU's laws that need to be updated. As we've said, battery-operated lights have come a long way in the past few decades.

Do you have a reference for that? I've done some quick searches to try and get a sense of what's true and what's rumor. From what I've found the rear blinkie laws in Europe are all over the map. In Germany they are disallowed, but other places they are fine. Otherwise the light laws seem similar to those in the US, except that a rear light (vs. reflector) seems to be more universally required. There also seemed to be more extensive reflector rules than in the US. i.e. in the Netherlands some sort of circular reflector on the wheel/tire.

Speedo

primarily, I know that imported dyno and battery lights from the EU all come with approval ratings from various EU countries, and that the German, French and Dutch taillights generally don't have a flashing function included.

battery operated lights may have 'come a long way' but the batteries themselves are still full of toxics.

Cool, thank you.

What scare quotes? Most standards are established by committees which are highly influenced by lobbying groups, so they are not all that high. With no intensive to improve manufacturers just do their best to meet those minimal standards. So if the lights become a requirement on the bikes consumer will be paying extra for lights that do not perform as well as, but would most likely cost the same, as lights that could be purchased separately. As for the rest of it. I already mentioned, multiple times, that I have corrected myself. I thought reflective strips were wider then they actually are. Nothing too ridiculous about that.

https://en.wikipedia.org/wiki/Scare_quotes

Commonly used to imply sarcasm...

Ah. I see, as in a light is required means a light with this certification stamp is required.

(edit) The Brits passed a law specifically allowing rear flashing lights. (/edit)

Speedo

I just checked with my friends that lived in the Netherlands for four years to see what their experience was with bikes and lights. Here's what they told me.

1) Lights are required after dark, and unlike here the law is strictly enforced with real penalties for non-compliance.

2) Bikes do not necessarily come equipped with lights. Sport bikes, typically, would not come with lights. Very low cost bikes may not come with lights. A "typical" Dutch utility bike would come with lights wired to a generator. As my friend put it: "Riders of utility bikes would complain mightily if they had to cough up more euros for lights, and conversely riders of sport bikes would complain if they had no choice but to purchase a bike with pre-installed lights."

Speedo