genec

Yup... gotta agree... one poster even had to gin up a whole new scenerio, just to "prove" how "wrong" the OP was...

lostarchitect 

My friend, lots of people out there don't seem to think about much of *anything* in their daily lives.

Leisesturm

I was being rather sarcastic...

dynodonn 

Our state law requires cyclists to have a white light on the front of their bicycle and a red reflector on the rear, when riding at night, but some cyclists have the bare minimum of lighting or no lighting at all.
There has been numerous times that I have encountered a cyclist only having one pedal or wheel reflector, which has been beneficial enough in garnering my attention to make me aware of their presence on the roadway, and make any necessary maneuvers or corrections, if needed at all.

trailangel

Ya know.. manufactures of bikes can go back to stainless spokes,polished aluminum cranks and rims, nice white or bright paint jobs.... easier to see. I am sick to death of black everything.
As far as how good reflectors work, if they work just one time.....they have done the job.

Looigi

If it hasn't been mentioned yet, these reflectors are more accurately described as retro-reflectors. They reflect light strongly only back toward its source. They do this either through having molded corner cube reflectors or embedded transparent spheres. They aren't very visible to observes that are far off axis.

vol

^ I had been watching this thread and amazed no one pointed this out.

Reflectors works when and only when (1) there is light, (2) the light shines from particular angles.

Those who say they work are thinking about the "when", those who say they are useless are referring to the "only when". Impressed with the length of the debate.

JoeyBike

I only have two good things to say about reflectors, other than their limited usefulness: Reflectors (1) never need winding or (2) never need batteries.

If the reflector is present, and clean, and positioned on the bicycle correctly, they just might work under a limited set of conditions. Most bike lights, if and when they die - you have nothing.

First visit to A&S?
.
.
.

vol

Need to be cleaned from time to time. I clean my pedal reflectors every once in a while. I see they work on other cyclists when they ride in front of me, thanks to my front lights. It would be nice if the crank arms are made reflective, too.

jfowler85

edit is mine


Don't be scared.


Bicycling at night - Performance of different reflector types This is some random person with a BS from MIT over 40 years ago, back when physics barely started to understand boundary-conditions of the universe. Basically he says the same thing as Sheldon, which is dependent on the reflector in question being only a flat surface. The obvious answer here is to use a reflector which covers a much wider entrance angle as aforementioned. You must have missed that part.


Bicycle Lights, Governmental Mismanagement
This is not a primary source, it is biased article summation. There are no actual sources of information herein; I asked for a citation and you pointed to more opinions. Surely you know the difference.


Your last statement defeats itself in favor of reflectors...the quote you raised lists limited headlight beam spread as a culprit of poor reflector performance. As you said, active lighting has changed a lot since the study in question (I can't review the link because it is inoperable by my browser so I'll give you the benefit of the doubt there) which necessarily means that, ergo, reflectors "perform" better than they did in the study (given that a RsubI is [luminous intensity]:[normal illuminance]).


There is an argument to be made for angle of observation...until you realize that it is overcome by using a reflector that, as aforementioned, covers a wider angle. Or use a second reflector as needed if you live in an area which sees heavy traffic in the form of lifted trucks, commercial trucks, etc. It's really not difficult, just a matter of using one's brain a little bit.


The paper most oft referred to in your links is https://www.cpsc.gov//PageFiles/117813/BikeReport.pdf which states on page 18 that half of all night-time cyclist/car fatalities involved alcohol...so we can throw out half of the evidence used against reflectors therein because it's not possible to tell whether or not the accident would have occurred if the cyclist would have used active lighting vs reflectors.


Neither the OP nor I have made the argument that reflectors work better than, or even as good as, quality active lighting. However, it's foolish to say something general like "reflectors are just a band aid and don't work", etc etc, especially when trying to back it up with soft sources and logical fallacy. I use both a reflector and a 1600 lumen MagicShine...both work great, especially on the stretch of road I take home which has a 45mph speed limit (interestingly, on that road is where drivers tend to give me the most room when passing, but at night - during the day I get buzzed on that road in the midst of morning rush hour, but because traffic is too heavy for some impatient drivers to give me adequate room).


TL;DR - Try again. Oh wait, I'm on your ominous ignore list (though you equivocally did not ignore me, hmm).

jfowler85

Already alluded to many posts ago:




The nature of a retro reflector is such that light needn't shine onto the reflector from a particular angle...that's the whole point. A simple mirror will bounce light off of it according to the Law of Reflection, but retro reflectors use internal surfaces advantageously to return light directly to its source. A sticking point for the anti-reflector crowd is to reference the limitations imposed by angles of observation and entrance but, as aforementioned, this is easily overcome by using a reflector that accommodates light sources from a wider angle spread. It's as easy as wearing a reflective belt or using a second reflector tilted upwards for the sake of lifted passenger trucks, semi trucks, etc. Case pretty much closed.

vol

I keeping thinking why manufacturers don't come up with a reflective BALL or taillight in the shape of a sphere. They would have 360 degree visibility.

Shimagnolo

Disco Mirror Ball-8" | Windy City Novelties

cyccommute 

Your state isn't unique. The requirement is part of the Uniform Vehicle Code for the US. Having similar laws between the states saves on a lot of confusion. I, however, would like to see the code changed so that rear lights are an available, legal option. You can certainly run a light with the reflector but I'd like to see it changes so that you could run active lighting instead of reflectors or that cyclists riding at night have to have a light on the rear like the requirement of a light on the front of the bike.

Just to be clear, I wouldn't want the CPSC specifying either front or rear lights nor would I want either to be integrated into the bicycle. The current "wild west" approach to bicycle lighting has resulted in some impressive technology for relatively little cost. If the CPSC or UVC specified what kind of lights we could use, I'm afraid that we'd be stuck with the German standard which is good for 18km/hour (11mph) but suffers at higher speeds.

mr_bill

Uh, UVC now requires:

12-702 front and rear bike lights at night.
12-703 It also requires a rear reflector at all times.
12-704 And side reflectors *or* lights visible from the side at night.
12.705 Additional lights and reflectors allowed, even blinky lights, but with limitations.

-mr. bill

Milton Keynes

Well, that's what makes them work, isn't it? Reflecting light back toward its source, maybe just a little off axis from your headlights to your eyes. No need to reflect light from your headlights over to the pedestrian on the sidewalk on the other side of the street.

Milton Keynes

Actually I'd say that having a rear taillight is safer than a rear reflector, and if the government truly cared about safety they'd mandate that instead of just a reflector. I certainly wouldn't ride without a rear taillight, but I do have both taillight and rear red reflector, and red reflective tape on the rear.

prathmann

No reason why it has to be an either/or situation. Many states require both a rear light and a reflector when riding at night. While active lighting is better in most cases, it is also significantly less reliable and requiring a reflector as well is a good inexpensive and lightweight backup for those cases where the light has failed or the battery is depleted.

cyccommute 

I stand slightly corrected. However, many states haven't adopted the language from the UVC as it applies to bicycles. It takes time to get statues passed and this one isn't a priority. Colorado's laws state

The requirement for a red reflector is a left over that needs to go. If you have active lighting, why do you need a reflector? I carry both...because the Colorado law requires one of them...but I just don't see the need. Also note above that the Colorado law only requires a red reflector but not active lighting.

Minor quibble, the UVC is Chapter 47-12-702. It's easier to find that way.

I agree and that's what I've been saying all along. Ditch the reflectors and require active lighting sufficient to be seen from the distances that the UVC requires...600 feet. If you go and read the CSPC report I linked to, even the CSPC says that the side reflectors are insufficient and unnoticeable from 200 feet. But, according to Forrester, they aren't looking into rectifying the problem.

This is a case of Big Reflector influencing our safety?

I-Like-To-Bike

Sees more likely a case of Forester dogma influencing your perceptions.

cyccommute 

I'm not that easily influenced. I don't agree with much he has to say but occasionally even a blind squirrel finds a nut.

10 Wheels

Local racers in the early morning.

KD5NRH

The "visible from x feet" thing bugs me, especially in regard to lights, since there are easily documentable ways to specify light output.

I can see a candle 600' away in the right conditions. It's visible, but it's sure as heck not going to catch my attention if I'm driving in traffic.

jfowler85

Not true.




Are you the squirrel or the nut?

prathmann

Agreed that the legal standard is pretty meaningless. Experiments with candle flames have shown them to be visible at distances of over a mile and some theoretical calculations indicate a maximum distance of up to 30 miles for visibility under ideal conditions. But a light with such meager output would be useless in making yourself visible in a traffic setting. Specifying the actual minimum light output would be a more meaningful standard.