Badly Aimed Annoyingly Bright Bike Lights
#1
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Badly Aimed Annoyingly Bright Bike Lights
Hey folks, if you have to run a headlight that's got a zillion lumen candlepower, at least have the decency to aim it correctly so you don't blind oncoming cyclists, down and to the right, just like properly aimed car headlights. Aiming your headlight into the eyes of oncoming cyclists is not only annoying, it's dangerous.
#4
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yeah, yeah, I blame the not-quite-fixed database, everything's still really slow. other forums let you delete your own thread, this one doesn't, so it'll be fixed as soon as a moderator gets around to it
#5
I've done photos and firsthand observation of my own lights, including ones I was attempting to devise a true beam "cutoff" for. Based on my observations, including video testing, a bright bike headlight isn't going to look a lot different when aimed down and to the right, unless you point it so far down that it's basically pointless to see forward with. The problem is that a lot of light is coming from a small source, and therefore it has high intensity per unit area. Compare the size of a 200-lumen bike light to the size of a ~1000-lumen automotive headlight lens... the difference in effective surface intensity must be approaching two orders of magnitude.
My solution: ride on roadways. If you're coming towards me, you're 10-20 meters to my left.
Oh, and the beam cutoff, as nice as it looked when aimed at a wall, was visually indistinguishable from the same light without a cutoff, at a range of about 50 meters. Sounds good, doesn't really work.
My solution: ride on roadways. If you're coming towards me, you're 10-20 meters to my left.
Oh, and the beam cutoff, as nice as it looked when aimed at a wall, was visually indistinguishable from the same light without a cutoff, at a range of about 50 meters. Sounds good, doesn't really work.
Last edited by mechBgon; 11-12-09 at 10:35 PM.
#6
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Bikes: Ummmm...Cannondale F4000..Ummmmm...Yeti ARC-X Cyclocross..Ummmm...Rocky Mountain Vertex TO with a BionX PL350 Electric Conversion...Ummmmm..Rocky Mountain Cardiac..Ummmm..thats it for now I think. I'd have to go look in the basement to be sure.
don't look at it.....
#7
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Hey folks, if you have to run a headlight that's got a zillion lumen candlepower, at least have the decency to aim it correctly so you don't blind oncoming cyclists, down and to the right, just like properly aimed car headlights. Aiming your headlight into the eyes of oncoming cyclists is not only annoying, it's dangerous.
As a result I shall continue to aim my 1200 lumens directly at your eyes.
Thank you
#8
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I've done photos and firsthand observation of my own lights, including ones I was attempting to devise a true beam "cutoff" for. Based on my observations, including video testing, a bright bike headlight isn't going to look a lot different when aimed down and to the right, unless you point it so far down that it's basically pointless to see forward with. The problem is that a lot of light is coming from a small source, and therefore it has high intensity per unit area. Compare the size of a 200-lumen bike light to the size of a ~1000-lumen automotive headlight lens... the difference in effective surface intensity must be approaching two orders of magnitude.
My solution: ride on roadways. If you're coming towards me, you're 10-20 meters to my left.
Oh, and the beam cutoff, as nice as it looked when aimed at a wall, was visually indistinguishable from the same light without a cutoff, at a range of about 50 meters. Sounds good, doesn't really work.

My solution: ride on roadways. If you're coming towards me, you're 10-20 meters to my left.
Oh, and the beam cutoff, as nice as it looked when aimed at a wall, was visually indistinguishable from the same light without a cutoff, at a range of about 50 meters. Sounds good, doesn't really work.

I was riding on the MUP tonight, not the road, so the oncoming cyclists were only like 1 or 2 meters to my left
Last edited by randya; 11-13-09 at 01:57 AM.
#9
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#10
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Hey folks, if you have to run a headlight that's got a zillion lumen candlepower, at least have the decency to aim it correctly so you don't blind oncoming cyclists, down and to the right, just like properly aimed car headlights. Aiming your headlight into the eyes of oncoming cyclists is not only annoying, it's dangerous.
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#12
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#13
lol...haven't seen a bicycle light, aftermarket or hand built, posted with a proper cutoff beam pattern/lens. They all look like high beams or flashlight beams. This is what a cutoff beam should look like:

Majority of the light should be focused where it does the most good...on the road and a flat beam projected down the road w/o blinding oncoming traffic and maybe highlighting elevated road signs on the right shoulder. Be better off using a small car fog lamp housing and lens and stuffing your hi-power/mega lumens/candlepower led's in there.

Majority of the light should be focused where it does the most good...on the road and a flat beam projected down the road w/o blinding oncoming traffic and maybe highlighting elevated road signs on the right shoulder. Be better off using a small car fog lamp housing and lens and stuffing your hi-power/mega lumens/candlepower led's in there.
#14
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Bikes: who cares?
#15
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lol...haven't seen a bicycle light, aftermarket or hand built, posted with a proper cutoff beam pattern/lens. They all look like high beams or flashlight beams. This is what a cutoff beam should look like:

Majority of the light should be focused where it does the most good...on the road and a flat beam projected down the road w/o blinding oncoming traffic and maybe highlighting elevated road signs on the right shoulder. Be better off using a small car fog lamp housing and lens and stuffing your hi-power/mega lumens/candlepower led's in there.

Majority of the light should be focused where it does the most good...on the road and a flat beam projected down the road w/o blinding oncoming traffic and maybe highlighting elevated road signs on the right shoulder. Be better off using a small car fog lamp housing and lens and stuffing your hi-power/mega lumens/candlepower led's in there.
#16
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From: in bed with your mom
Bikes: who cares?
, otherwise people might think you're just another jackhole that runs badly aimed annoyingly bright lights
#17
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I don't run lights at night also I wear dark clothing and no helmet.........But I am aware of my surroundings...so I never get hit or messed with by the police!
Key word is aware! You must be aware at all times.
#18
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I definitely run lights, but I run sensible ones that aren't overkill or so poorly designed as to be hazardous to other users
#19
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Bikes: Too darn many.. latest count is 11
Need some cheese with that whine?
#20
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Bikes: who cares?
#21
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From: Columbus OH
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#22
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From: Columbus OH
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Really be honest....how many more car lights do you come across than cycle lights during your ride??? You must have had a bad day with your micro manager boss!
#23
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If you live in a country where lots of people ride at night you'll find enough pissed off car drivers to make laws about bike lights.
And you'll find bike light makers making proper lights like this:
https://peterwhitecycles.com/headlights.asp
#24
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I live in PDX and I went for a ride on the MUP after dark but still during commuting hours tonight, so the answer is I saw LOTs of bikes with annoying lights this evening. I think it's great that cyclists are lighting up, but they need to be more aware of how the equipment they are using affects other cyclists, particularly if they are riding on the MUP, where the effects of bad lighting equipment on other cyclists are much more pronounced than on the road, because separation distances are much less on the MUP.
#25
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The only bike lights I am aware of with a really good vertical cutoff are the German street legal lights that Peter White cycles imports. Germany has basically the same sharp vertical cutoff rules for cycle lights as for the low beams of German road legal car lights. As a result their street legal bike lights have the least annoying light patterns for fellow bicyclists and motorists. I believe that German law also limits the power of street legal bike headlights.
Most American bike lights have a round beam which puts out too much light above the horizontal so it is difficult to aim them low enough to not be annoying to others and still have adequate illumination for reasonable speeds. They are equivalent to an automotive high beam.
Most American bike lights have a round beam which puts out too much light above the horizontal so it is difficult to aim them low enough to not be annoying to others and still have adequate illumination for reasonable speeds. They are equivalent to an automotive high beam.
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Gear Hubs Owned: Rohloff disc brake, SRAM iM9 disc brake, SRAM P5 freewheel, Sachs Torpedo 3 speed freewheel, NuVinci CVT, Shimano Alfine SG S-501, Sturmey Archer S5-2 Alloy. Other: 83 Colnago Super Record, Univega Via De Oro
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