it's entirely possible, and i'm sure it's happened at least once, that someone on a bike does something unsafe and illegal, causes a motorist to swerve, and the result is a motorist fatality. this can and does happen (rarely) when a cat or dog runs into the street, so it can happen with a bicycle.

of course, a bicyclist is not a serious threat to motorists' safety... while motorists are very often threats to bicyclists' safety.

That's a little harsh on him I think. As a kid I played with op-amp circuits driving led's and I could modulate the brightness, up to a point. (that being, the point where you smoke them).

That's been my experience, too, with friends who've been stopped for riding without lights -- never a ticket, except one who was drunk enough they didn't even let him walk home.

With what traffic enforcement costs I can see why police tend to focus on the higher public safety threats. (Even with ticket revenue, traffic enforcement is a net cost to the police. We've had to reduce our traffic enforcement considerably with the current economic situation.)

I had stated that you don't see bicyclists taking out cars, and you showed me three examples of bicyclists taking out pedestrans. That is a big difference. Be that as it may, here you are saying that a bicyclist is endangering him/herself as much as other riders with the lights.

Okay, not disputing that. I can show a tons of examples of cars banging up bicyclists because they didn't see them. Could you show me where bicyclists with bright lights have cause something. I am the newbie and the layman, I am just trying to learn.. :beer:

If you were to hit and run away, you might end up with an impounded car. I know from first hand experience, unfortunately, that your car will not be impounded as evidence. The police will investigate and take statements but you will be on your way in short order.

You might be able to find an example like smasha's but I think it would be incredibly rare. Cyclists...even incredibly stupid ones...are hardly going to dart out in traffic like a squirrel or dog. Even then, the motorist could have no one to blame for an fatality because they are to keep their vehicles under control at all times.

However all this talk about cyclists blinding drivers is silly. Stop and consider where we cyclists ride in relation to motor vehicles. Our lights, even ones with a very wide beam, are further over from the driver of a car than even the passengers side headlight of a car coming at them. Since light travels in a straight line, the likelihood of 'blinding' a driver is very low. Also consider that our lights are usually of a lower intensity than automobile lights.

Further, if your light sprays an excess of light away from the central beam, the light isn't going to have enough lux (a measure of intensity per area) to be blinding. For a light to be 'blinding' it has to have a lot of lux over a very small area. As you move away from the lamp, the intensity of the light decreases with the square of the distance. Thus a typical high intensity bicycle light that has a lux of 40 at 1 meter will have a lux of 10 at 2 meters and a lux of 4.4 at 3 meters and so on. Car headlamps have a lux of 0.15 at 250 ft. To reach that level of lux with a bicycle light you only have to go out 16 meters (52 feet). To give you a way to think about it, 0.25 lux is what a full moon is like on a clear night. Hardly blinding.

@cehowardGS , I am not disagreeing with you, but I am also saying that just because it isn't reported doesn't mean it doesn't happen.

@cyccommute, re cyclists darting out - only 2 days ago did I come inches away from flattening a cyclist with my bus, who had cycled out from behind a building at speed and off the raised kerb of the bus stop I was pulling into and across a whole lane of traffic.

Re the blinding, I don't fully disagree - but you should a) see some of the front blinlkies round here (number are not the whole story where light is cpncerned) and b) stop assuming that eveyone cycles where they are supposed to - a lot do not.

And do not forget that "blinding" people takes far less light than during the day due to the dialation of the pupils to allow more light to the retina to see better in darker conditions.

But consider the speed that you were traveling. Driving a bus, you would hardly be traveling at a speed where a crash would be fatal to you. The cyclists is another story.

Yes, you get glare from a cyclists light. And, yes, your eyes are drawn towards the blinking light so that you notice them. But glare and noticing a light are hardly 'blinding'...not if you use the definition of to be blinded as having your vision so impaired to the point where your eyes no longer function. You aren't 'blinded' by lights on a police car when it is has it's flasher on are you? The ones here in the states can be very bright and very distracting but they aren't going to impair your vision. Bicycles seldom get to that level of intensity.

Blinding means to deprive of sight. You may encounter lights that are uncomfortable but, unless you have some kind of visual problem, they aren't going to deprive you of your sight. I can look directly into the lights on my bicycle from inches away and I'll see blue spots for a few seconds afterward but there's no permanent damage that deprives me of my vision. And, as I pointed out above, the intensity rapidly diminishes with distance.

Further, if you are traveling in an urban environment, your night vision is already severely diminished. Even using the lights on a car will drastically diminish your night vision.

My experience differs, even non-fatal serious accidents can result in a car being impounded, especially if the driver is in custody. A driver who kills a pedestrian in a crosswalk is not likely to be on their way in short order, unless you mean on their way to jail.

Many bicycle headlights on the market today are considerably brighter than automobile high beams, and if you read through this thread and others addressing this concern, you'll find plenty of riders who say they intentionally aim their lights at the eyes of oncoming traffic "to be seen".

If we could rely on riders to aim their lights properly, then you're right, blinding drivers with the spillover from a narrow beam that isn't aimed directly at the drivers' eyes would be unlikely.

I try not to make my light too offensive. There is a difference between being seen and being aggravating. I can see a car coming at me with his high beams on but it sure is irritating and doesn't make him more visible than if they had their low beams on. Have you ever looked directly into one of these lights? The XML emitter will mess up your vision for a bit and if you have it on strobe that can create a dangerous situation. Be smart about how you use your lights and think about how you would feel if you were on the other end of the beam.

it's not about speed, so much as force: F = ma. compared to even a small car (going slow), a large person going fast on a bicycle doesn't have much force. but there's an instinct to swerve even if a squirrel runs out in front of a bus. this happens. sometimes the squirrel survives and the bus driver, passengers, and/or other motorists don't.

there's a lot of variables in this... riding in NYC or las vegas at night, it would be hard to blind oncoming traffic with a headlight because there's so much ambient light... but out on a rural country road at night, i could easily blind oncoming traffic with a few hundred lumens, from a reasonable distance. if their windshield is dirty and caked in mud & grime (as many windshields are) that reduces the power and increases the distance needed to blind them, or impair their vision, with a bright light.

another variable is (always!) alcohol and other drugs. it's not uncommon that drunks crash into the backs of emergency vehicles with flashing lights... on open roads with clear visibility. for whatever reasons, they didn't "see" it!

most of us who have experience behind a wheel, especially in rural areas, have experienced being "blinded" by a car with an improperly adjusted headlight (or driving a small car and being tailgated by an SUV or truck). LED technology now brings MORE light output than an automobile headlight (often in part of the spectrum that is perceived by human eyes as brighter) to bicyclists.

how much output does a typical 100W halogen headlight put out? about a 1000 lumens? for <$200 we can beat that with LEDs on a bike, mounted at motorists' eye level!

with power comes responsibility. i've said it before, i'll say it again... it's only a matter of time now before laws will limit the power output of bicycle lights (or at least require certain beam patterns and proper aiming). right now the technology is ahead of the law, but the law will catch up... eventually.

How about you provide a concrete example of people in a car, bus or truck being 'killed' because of a squirrel? If you swerve to avoid a squirrel and end up dying for it, you are either going too fast for the conditions, shouldn't be driving a vehicle because you can't control it or a combination of both.

What part of urban don't you understand. Even in a rural situation, your car has lights that are more than powerful enough to ruin your night vision...not that you should depend on your night vision to drive on a rural road. Most of the time when I'm driving on a rural road, I try to drive as much of it as I can with the brights on which definitely impairs your night vision.

Not really germane to the discussion. In other words, a red herring.

Yep, I've experienced bright lights in rural areas. But I never been 'blinded', as in deprived of the ability to see. Even when someone forgets to dim their bright lights, I can still function and drive down the road. It's not like the road suddenly goes black and I have to drive by feel. If my eyes did quit working because of a bright light, I'd immediately pull over and call 911 because you shouldn't drive if you cannot see.

LED technology does not bring more light output than an automobile's light yet...at least not in an affordable package. Getting a bicycle lamp with a car lamp power costs more than $200. Yes, you can get bicycle lamps that put out an actual 1000 lumens but they aren't the $200 ones. There's whole bunch of bike lamps that 'claim' 1000 lumens but deliver far less.

A typical car headlamp output is 1500 lumens. But a much more important measure is the lux (lumens/area). I gave the lux above for an automobile lamp above which was 0.15 lux at 250 ft. That's 250 feet away. At 16 feet, the lux from a car lamp is going to be much, much, much higher. And there are two of them on a car and the car coming at the driver is closer to then a bicyclist is.

In Toronto the cops occasionally stage a massive bicycle safety blitz, usually at the beginning of the cycling season in the spring. Typically, they set up traps to ticket cyclists for running red lights, failing to stop/yield, etc. This past summer they infamously set up a 'bell blitz' and ticketed over a 100 cyclists for not having a bell ($110!!!), which many here decried as a major waste of resources and hugely missing the point. While a bell is an important piece of safety equipment, I would argue adequate night lighting has a greater overall impact on cycling safety. Yet, the police have never gone on a 'light blitz'.

how about dogs?

Teen dies in car crash trying to avoid dog
http://www.actionnewsjax.com/content...Qg0_POWJQ.cspx

Man crashes into church sign after swerving to avoid hitting dog
http://www.kxxv.com/story/16350242/m...id-hitting-dog

Texas A&M OL Killed In Car Accident
http://www.ktvz.com/sports/30062664/detail.html

there's three reported fatalities, none of which mention excessive speed. here's one with a squirrel that does...

OHP: Speed A Factor In Death Of A Tulsa Man
http://www.newson6.com/global/story.asp?s=10191785

nope. if you're driving on an interstate highway with light traffic and good visibility, 65mph could be a very reasonable speed... but if an animal runs out in front of you, and you swerve, it's fast enough to easily be fatal.

sure, motorists have to be "prepared for the unexpected" but that doesn't mean always driving slow enough to safely stop within 25 ft.

then you've got some combination of:
a- exceptionally good eyes
b- a lot of driving experience
c- not much driving experience in these conditions
d- a very clean windshield

note that "b" and "c" are mutually exclusive.

with experience and a clean windshield (and being sober, well rested, etc) this situation can be "partially blinding" rather than "blinding" but it still leaves your visual abilities compromised. if someone is shining a bright light IN YOUR FACE while you're driving in the dark, you are at a disadvantage. there's no way around that. this point is not negotiable.

what bulb do you consider typical? my last car had 9006 headlights - 1000 lumens

lights like the MJ-856 & MJ-872 are rated 1600 lumens, and they've been independently tested around 1200 lumens, OTF. that's real-world brighter than 9006s, and they retail for <$200. meanwhile, LEDs keep getting more efficient, brighter, and cheaper.

those two lights are "floody" compared to earlier magic-shines but still enough power to "blind" other road users. most bike lights produce a very tight "spot" which maintains a blindingly bright light, even at a considerable distance.

Its beside the point too. Just because they "should" be able to control their car to some "reasonable" expectation doesn't mean that in every instance they will. You have to assume that they probably won't. They give drivers licenses to just about anyone that passes a basic competency exam.


Something to note about the bike headlights too is the pattern of the beam. Our lights are concentrated on a much smaller point and dont have as much control where as car headlights are specifically designed to NOT blind oncoming traffic while providing appropriate light on the road.

BTW, if I ride around with my MagicShine T6 XML clone on high aimed level I get very erratic behavior from drivers. Many will also flash their high beams at me.

The same can be said for most of the more than 30,000 traffic fatalities in the U.S. each year -- if we could trust drivers not to go too fast for conditions, or beyond their ability to control their vehicles, we could close trauma centers all across the U.S.

First off, this is a very constructive debate!! :beer:

We need some STATS here!! :D

A bicycle vs 3000+lbs of moving steel is NO-WIN for the bicycle. From my limited experience on the bicycle, I see that BEING SEEN, SHOULD, not saying I am correct, but BEING SEEN should be priority one for the bicycle rider!

In addition, on these bicycle lights, yes, the tech had skyrocketed on these lights, and they are better, but how many bikers got those high price super bright headlights? Taking a guess, I would say about 5% of bicycles that run lights are running those high price super lights. I am just taking a guess. I got 9 bikes. I am running $3.00 lights on two of them, and $25 lights on another two. I take care even with my el-cheapos to point them downward and not upward. But, I do want to be seen..

In the morning when I leave for my commute, it is dark. I have to get on a 30mph single lane in each direction, with no shoulder(I have to take the full lane) and the cars are zooming by at 50 and 60 mph.. When I merge out into the traffic on that road, the cars coming up behind me MUST SLOW DOWN.. They are doing a minimum of 40 mph.. If they don't see me, and here I am come with my 10 to 12 mph starting speed, going up to about 18 mph, then I am toast. Now, in a situation like that, am I supposed to be worrying about blinding those car drivers with my front or rear lights, or should I be worrying that these cars do see me and slow down?? I am 100% on the latter.

One would say, why do I travel that road? Well, it is the only way out for me. I go another route, it triple times more dangerous. Again, the most lights I am running are a PB 2W Blaze up front, PB Beamer blinky on my helmet, and a Superflash Turbo on the rear.. That is about $60 worth of lights.. For me riding that dangerous road, I am way UNDER LIGHTED.

IMO, I like to see some stats on bicycles with bright lights causing hazards/accidents/deaths!!

IMO, the lights on bicycles irritate a lot of people just like the bad bikers who don't obey the laws. But, even the bad bikers are not causing mayhem out there. Of all the car drivers on the road, 80% of them can't drive. I got that stat from over 50 years of driving on the roads. You should see the stuff that car drivers do.

Again, this is my opinion, but the stats will tell it like it is. Is the car more dangerous to the bicycle, or is the bicycle more dangerous to the car..

:beer:

Why are people talking about controlling the behavior of the drivers and what they must or should do? You can't control them. Take that to A&S.

Flashing tail lights are fine. Most people don't aim them at the drivers eyes. We tend to put them on the rear racks and forks. Sometimes we put them on our helmets to get them up nice and high but for the most part the red blinkies aren't offending or blinding anyone.

The headlights on the other hand are mounted on the handle bars which on most bikes puts them eye level. Aimed straight out they will be directly in the eyes of most drivers. I'm not concerned about the standard blinkie or the be seen flashers either. I'm talking about the emitters and torches here. Those are the ones that can make some people disoriented when in flasher mode at night. Its not even just drivers.

My point is to consider the power of the light and where you aim it and then put yourself on the other side of it. Maybe think of how grandma's eyes might react to a bright 1000 lumen strobe aimed right at her eyes while she is operating her 2 ton brick as it hurtles towards you. Ya might want to aim it down a little or not strobe that sucker.

safety is the most important thing. that means not getting hurt and not hurting others. being seen is part of being safe, as is self-education, paying attention, keeping your bike in good repair, knowing the limits of yourself and your bike, riding smart, etc.

being seen is just a piece of the puzzle.

i'm not aware of any documented cases of injuries or fatalities, but as LED technology keeps getting brighter and cheaper i'm sure it's only a matter of time. as noted earlier in the thread (and elsewhere on the site) some motorists respond to bright bike lights the same as they respond to an oncoming car with the high-beams on: they flash their high-beams! that means they have no idea if you've got a car or truck with a headlight out, a bicycle or motorcycle, or a UFO... all they care about is that you're shining too much light at their face! that's how oncoming traffic asks you to turn it down a notch. there doesn't have to be a fatality for me to understand that that has already exceeded the amount of light that is safe and reasonable to use when there's other traffic on the road.

with your blaze-2W (about 80 lumens, very tight beam) you WON'T get oncoming traffic flashing their high-beams at you. you might piss someone off if you stop directly behind them, and shine that "super flash" strobe directly into their rear-view mirror. i've got a blaze-2W (flashing) and a light-star-300 (steady) on my handlebars, and when i stop behind cagers (in small cars) i turn my wheel to the side: i would NOT want those lights pointing directly at MY rear view mirror!

what i can document with ease, unfortunately, are bicyclists who are killed while riding with no lights. that's too common. FSM only knows how many bicyclists are killed because they used weak "blinkies" (with weak batteries) instead of reasonably bright lights: when they're killed, the police reports tend to not comment on what lights were used, if the batteries were charged, were the lights clearly visible to others... they just (usually) report "yes or no" if the bike had lights, and if any witnesses commented on noticing the lights or the absence of lights.

Good points, but let me add this. When comparing cars to bicycles, one has to INCLUDE THE NUMBERS. For instance, you mention that car lights are designed not to blind, but bicycle lights are not(I think that is what you are saying), from just a guess, on the road, theer are about 10000 cars to every bicycle. That is my own off the top of my head stat!! :D

Even if I am wrong, say the ratio is 5000 to 1, or even 2000 to 1, same rules don't apply to bicycles. Why.. You bump something at 15 mph in a protected car, 10 out of 10 you not hurt. You get knocked down at or even fall down at 3 mph on the bike, you in trouble. Comparing rules for cars to bikes is not the way to go or fair. Bicycles must be seen. The is their #1 protection against cars. You can be the safest, abide by every bicycle rule in the world, if a car doesn't see you, you in big trouble. That is the point I am making.. :beer:

I agree with all the above. However, on the "not hurting others" shouldn't be on the same level as "not getting hurt".

Let me explain. Say, I am a ROGUE BICYCLIST and I have blown my marbles (crazy), and going out to purposely do harm to others. I jump on my bike, first I try to run into a car, I lost that one, then I try to run into a truck, lost that one too. Okay, I see some folks walking across the street, I gather as much speed as I can, and I run into them. I say about 200 times of doing that, I might manage to kill somebody, just might. Now, I put some $700 lights about 4 of them on the front of my bike. Aim them so they hit drivers right in the eye..I think I could ride for a week with those 4 blinding lights, and the worst I get would be my butt kicked from a irritated driver who caught up with me. That's it..

Now, give me that car, and let me see how much damage I can do. No need to even list any example of the damage I could do if I went beserk in just a sub-compact. I said all of that to state, the bicycles are VASTLY different on the hurt-to-people ratio then cars.

I am sure there are some documented cases of bicycles causing fatalities, but just like I always say, look at the ratio!! Again, an off-the-top-of-my-head-stat, there are about 100,000 car caused deaths to every bicycle caused death. That is why the lawmakers are NOW, creating more laws to protect the bicyclist. They just put into affect the 3-foot rule in my state/town.

All of us here in thread want the same thing. Safety for us on the bicycles, and safety to others. Since OTHERS are more dangerous to US, we have to put US first. That has been my whole point.. :beer:

Very good points!! :thumb:

What I think is needed, is to INFORM our brethen on how to properly aim front lights on a bicycle. Example, just like the hazard warning on cigerettes, have a warning on all bicycles lights packages to "aim them in a way as not to distract or temp blind on coming drivers"!

I think a lot of the OFFENDING BICYCLISTS are not doing it on purpose. They are doing it through lack of KNOWLEDGE. The more this is put out there, the more riders get educated in their lighting system.

I for one, learned A LOT. Just been into bicycles maybe about 2 years.. Now, I am starting to commute. Moving up the ladder, my commute NOW is starting in the dark, and ending in the dark. Didn't have to be rocket scentist to know that I needed some lights!! I am on the bottom end, but I am getting a lot of know-how from these threads, a lot. This morning, I am off, but the urge to ride was too strong. I had to do the first leg of my commute even though I am off. I opted for my 85 Raleigh Prestige. She is decked out in with a PAIR OF $2.00 each lights up front, and a $2.00 blinky in the rear. I have a PB Beamer on my helmet, and on each one of my legs, I have a $2.00 blinky, along with a safety vest. My two prize el-cheapo front lights are hitting the ground about 25 to 30 feet in front of me. BTW, these $2 gizmos do have a high beam too.. :D I am running the high beams..

If fact, here is a picture of the rig I rode this morning. And my two headlights have feelings, so no wise cracks!! :D

http://www.cehoward.net/powerbeam46.jpg

No mention of speed so you just assume that the speed is wasn't a factor? You don't roll a car over "several times" or roll your car over and smash through a brick wall or if you are traveling at a moderate speed. And driving your car into the front of a truck because you want to avoid killing a squirrel is just dumb.

The troopers investigating the accident "speculate[d] the driver lost control of the car while attempting to miss [the squirrel]" based on a freshly killed carcass at the scene. However, if you tear your car in half and hang it about 4 feet up in a tree, avoiding the squirrel wasn't the problem.

Just like the truck example, if you are so concerned about an animals death that you are willing to swerve to avoid it at 65 mph you are being beyond dumb.


What are you considering to be 'blinded' by another automobile's light? A bit of glare can be uncomfortable but you aren't going to be unable to see. If that is the case, you shouldn't be driving.

Motorists shine their lights in the face of oncoming traffic all the time. The world isn't flat and straight, it's full of turns and hills and curves. Having a light shine in your face from in front of you or behind you is a fact of driving a car. I was trained long ago not to stare into the lights of on-coming cars.

To get the discussion back to bicycle lights, we have a very hard time shining our lights in the face of motorists...if we are riding legally and safely. We are just too far way from the drivers with too weak a light to do so on a regular basis. If you are turning left, your light might be shining towards a motorist on the other side of the road but that would be the case with a car turning left as well.


The 9006 halogen bulb is on the low side of bulbs available for cars.

The claimed rating of the Magicshine lights are well known to be inflated. MTBR's lux measurements (a better measure of light output) put the MJ872 at a lot lower than other bicycle lights with a similar output whose output claims are more trustworthy.

I think this is the key to the discussion. Lots of fellow cyclists equate irritating with blinding. It's a matter of semantics. For me, to be 'blinded' means to be deprived of sight. To others, it seems, to be 'blinded' means to be uncomfortable. I can still function in a vehicle if I'm merely uncomfortable. I can't function if I'm blind. In many years of driving at night I've never be 'blind', i.e. unable to functionally see.