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Question: How important is light cutoff?

Hi! I'm new here - just purchased an Airborne Guardian 2.0. It hasn't even shipped yet, but I'm researching lighting options under $100. Most of my riding will be in the evenings after the kids go to bed. I have a couple high output LED flashlights, but I'd like to get dedicated bike lights. I've seen several posts stating that flashlights are a bad option because they blind oncoming traffic, but the highly regarded Nitefighter BT21 & BT40S combo don't seem to have cutoffs (and are likely much brighter than most flashlights).

Most of my riding will be in my (VERY) dimly light rural neighborhood, with concrete paved streets and walking paths (through heavily wooded areas).
 
I wouldn't worry about cutoff beam on your lights. Just aim the light down a bit at the road and not straight out in front of you. I run the same lights on trail as off, but on the road I'm generally using lower output. Flashlight beams vary greatly so for people to say that flashlights are a bad option isn't accurate. Yes the Nitefighter lights you mentioned are an inexpensive option and seem better quality than the average Chinese lights. I bought the BT40s simply because it was so cheap and they are one of the few offering neutral white options right now. The Bt40s is a bit floody for road riding and more suited to trail IMO, but still it will work. The neutral white beam is what makes the Nitefighter lights desirable right now and if it came in the standard cool beam color most of us probably wouldn't give those lights much thought. Well I guess the battery pack is of decent quality too compared to the typical junk Chinese packs so it has that going for it too, but they are also priced a bit higher than the typical Chinese stuff too. My only concern is waterproofness of the nitefighters, but time will tell on that one as I haven't given it a rain test yet. You are right though the nitefighters don't have a cutoff so they aren't going to be any less offensive to oncoming traffic than the typical flashlight beam other than the neutral tint is less harsh on the eyes.
 
I believe some countries require lights with cutoffs, such as Germany. We don't have that here in the US. You can aim them a little lower if necessary, or just lower the intensity of the lights if the drivers start getting pissed.
 
if your going to be riding just roads, dont use high powered lights like we do on trails or make sure they at least have lower settings (thankfully most bike lights do), angle them down. The thing of not using "flashlights" isnt a thing of directly angering drivers if used properly, they work just fine on the road as long as your responsible. Flashlights are more of a run time issue but any bike lights are going to piss drivers off if not used correctly. Ones with cut off beams just have a ledge that sticks out over the emitters on top so the cut off does NOTHING unless the light is pointed down like it should be anyway.
 
Do I need lights with cutoff beam pattern?

No....but for the type of riding you mentioned they could be better if the design were right.

MaximusHQ pretty much nailed it. Aim the lights down and you should be fine. For something like paved commuter paths a lamp like the NF BT21 can work very well when on the lowest level of output. Pointed down and on low ( it is very low ) it works very well and shouldn't blind any on-coming traffic.

Personally, for the type of riding you suggest I usually use a single emitter LED torch set on one of the low settings. Once again pointed down it is very inoffensive to direct on-comers and still allows me to see what I need to see. On roads ( with no direct head-on traffic ) I'm more inclined to use a regular dedicated bike lamp ( set at an appropriate angle and output ).
 
One thing I would like to add is I wouldn't be overly shy about using a bright enough light level to see the road in front of you well. Years ago I would run my lights too dim to see everything in front of me especially with oncoming traffic. I ended up riding right through potholes and whatever garbage littered the side of the road. Luckily on was on my mountain bike and it got me through without crashing. Now I run what ever allows me to see the road clearly even with oncoming traffic. There is more for a cyclist to lose if they hit a big pothole and crash then if some motorist is offended by your light light has to slow down. Sure have consideration for the motorists, but worry about your own safety first.
 
If you want to go with a flashlight, try one with a small reflector/lens size like the highly regarded Convoy S2+ (my EDC is a Convoy S2 neutral white). Smaller reflector means the light is flooder and therefore not concentrated into a motorists eyes. The beam being more floody means it's more even rather than having a really bright hot spot with dim spill.

-Garry
 
One thing I would like to add is I wouldn't be overly shy about using a bright enough light level to see the road in front of you well. Years ago I would run my lights too dim to see everything in front of me especially with oncoming traffic. I ended up riding right through potholes and whatever garbage littered the side of the road. Luckily on was on my mountain bike and it got me through without crashing. Now I run what ever allows me to see the road clearly even with oncoming traffic. There is more for a cyclist to lose if they hit a big pothole and crash then if some motorist is offended by your light light has to slow down. Sure have consideration for the motorists, but worry about your own safety first.
I have to agree 100%. When on the road you use the light in a way that both protects you ( get's you seen ) and lets you see what's in front of you. While you don't want to annoy people personal safety ALWAYS takes a priority. Besides, the way I look at it if you drive a car at night on a regular basis ( like me ) almost every vehicle represents a minor annoyance. Bright lights are "bright lights" and while driving they are all around you. Eventually you get used to the occasional "Superbright" car or truck lamps and learn to deal with it. This is why I never overly criticize someone using a bright bike lamp when on the road. For the most part they are extremely rare and generally not an annoyance factor anyway. Besides it really makes no sense to overly criticize a cyclist using a bright lamp when many motor vehicles are using much brighter lamps that are much more annoying ( and much more common ). The cyclist on the other hand needs to see what's in front of him and just as important, needs to be seen. Being seen helps keep him alive. Bright lights help him/her achieve that goal. If any criticism is to be levied at cyclists it is usually because "They DON'T USE BRIGHT ENOUGH LIGHTS TO GET THEM SEEN".

I personally have never seen a road cyclist using a lamp that was too bright. On the other hand about 80% of the people I see riding bikes on the road at night are not using lights bright enough to get them ( adequately ) seen or to draw attention beyond a couple hundred feet...and Oh how I wish that wasn't so.

Last night I saw a guy that was using a very nice set-up ; bright front lamp, bright rear lamp and a couple small wheel lights on each wheel. When you see something like that on the road it is almost impossible NOT to notice them.

If you want to go with a flashlight, try one with a small reflector/lens size like the highly regarded Convoy S2+ (my EDC is a Convoy S2 neutral white). Smaller reflector means the light is flooder and therefore not concentrated into a motorists eyes. The beam being more floody means it's more even rather than having a really bright hot spot with dim spill.

-Garry
Yep, that the Convoy S2 was my newest purchase. Makes a great back-up or commuter lamp.
 
The thing with a cutoff light beam is that you get the light where you want it. On the road in front of you so you can see the road without blinding traffic. With, let's say BT21, pointing down on low you will see much less of the road and still blind traffic more than for example a Philips Saferide (I know I have both lights and I have done som tests).
 
Discussion starter · #10 ·
Thanks for the responses everyone. I ended up ordering the Cygolight Dash 320 for my bar light. I wanted something bigger/badder/brighter, but I think the Dash will do fine for my type of riding within my sleepy country neighborhood. I'll strap one of my flashlights to my helmet for now. Maybe once I prove to myself (and my wife...) that I can really get into cycling, I'll pony up for something better.
 
The thing with a cutoff light beam is that you get the light where you want it. On the road in front of you so you can see the road without blinding traffic. With, let's say BT21, pointing down on low you will see much less of the road and still blind traffic more than for example a Philips Saferide (I know I have both lights and I have done som tests).
While I can see some advantage to a cut-off beam pattern for commuter paved paths where there is the possibility of direct on coming traffic, I don't think that such a design is necessarily the best option for road use. On the road you actually want to be seen by traffic that is approaching and you also want to see things in the peripheral that might become a hazard to you cycling at night. From that perspective a "cut-off" beam pattern could be considered counter-productive. Unless we start talking about lamps that emit over 2000 lumen and are in very close proximity to another person I don't think any lamps designed for bike use are going to be a major hazard or annoyance to vehicles that are driving down the road. ( when used properly )

If you routinely drive at night ( like me ) you see many sources of bright lights that are terribly annoying. There are cars with the new LED/HID lamps, trucks with lamps that are mounted higher, emergency vehicles with high power strobes, road construction crews with lamps designed to mimic daytime conditions, the list is almost endless. Not to mention that almost everyone has had to drive into the sun during sunset at some point. A bright bike lamp pales in comparison to ANY of these things.

If you're going to criticize a cyclist using a bright bike lamp you need to put all other road factors into the proper perspective in order to give the night cyclist a fair shake. It continues to baffle me that I consistently read ( from other people's posts ) how very bright bike lamps are, "Blinding to road traffic". To me this idea is one of the biggest urban myths I have ever come across. When I drive at night I get blinded almost every night by various vehicles or various sources of bright light. When I say "blinded", I'm talking about the need to either look away from where I'm driving or to adjust my mirrors or to lift my hand to shield my eyes. The only time I've every been blinded by a bike lamp was while mountain biking on trails and I came upon someone else using bright lights ( direct head on traffic that passed me in very close proximity.)

Lately I've been seeing more people using bright LED bike lights when riding their bikes on the road. This pleases me because the last thing I want to do is run into someone riding a bike at night. The more these people stand out the better and more safer they are going to be. Never, and I mean NEVER have I ever had to either turn my head away or lift my hand to shield my eyes from someone riding a bike with a light that was too bright ( when on a road ). In the future if that ever happens I'll be sure to talk about it.
 
The thing with a cutoff light beam is that you get the light where you want it. On the road in front of you so you can see the road without blinding traffic. With, let's say BT21, pointing down on low you will see much less of the road and still blind traffic more than for example a Philips Saferide (I know I have both lights and I have done som tests).
Any light with a conical beam if aimed down at one half the angle of the cone apex will put all it's light on the road in front of you in an oval shape.

For example, my Lupine Wilma has a 26 degree wide beam in a cone shape. If I aim it down at more than 13 degrees, there is little light (spill only) that is going down range that is not eventually hitting the ground. The pattern in front of me is a long oval starting about 5' in front of my front wheel with spill lighting up the area between that and my front wheel/handlebars.

Aiming a light now by 15 degrees is pretty minimal. No blinding occurs.

J.
 
Any light with a conical beam if aimed down at one half the angle of the cone apex will put all it's light on the road in front of you in an oval shape.
Yeah, but you get too much light just in front of your wheel. And too little further down the road. And it still blinds. Have you tried look into your Wilma from a distance angled down 15 degrees?

One big problem is that there is no bright enough light out there with cutoff beam. I've just discovered the potential by using a Philips Saferide. I like the idea to reflect the (little) light there is where you want it instead of just waste a lot of light in a conical beam.

You dont see the emitters if you look into the saferide. It is just secondary light coming out of the light head, and the reflector puts the light exactly where you want it. It is really effective use of the little light the saferide gives.

And I don't think it is a good idea to blind on coming traffic to be seen. There are much better ways...
The germans have understood this with their StVZO standard.

Please, can't some engineer somewhere construct a decent bike light for road use.
 
Yeah, but you get too much light just in front of your wheel. And too little further down the road. And it still blinds. Have you tried look into your Wilma from a distance angled down 15 degrees?
Depends on the width of the beam but with a 26 degree beam of the Lupine Wilma, aimed as described, it works perfectly. And it is no more blinding that a car headlight is. I typically ride with the lights at about 1500-2000 lumens and go to the full 2400 lumens for high speed descents when there is no opposing traffic. Properly aimed, you have *plenty* of light and it's on target and not blinding. Same is true of car headlights, by the way.

One big problem is that there is no bright enough light out there with cutoff beam. I've just discovered the potential by using a Philips Saferide. I like the idea to reflect the (little) light there is where you want it instead of just waste a lot of light in a conical beam.
A properly aimed conical light doesn't waste much light at all. Do the math. If you aim it straight out ahead, yeah - it will waste half the beam. But that's silly, just aim it at slightly more than half the width of the beam down and it's all fine.

You dont see the emitters if you look into the saferide. It is just secondary light coming out of the light head, and the reflector puts the light exactly where you want it. It is really effective use of the little light the saferide gives.

And I don't think it is a good idea to blind on coming traffic to be seen. There are much better ways...
The germans have understood this with their StVZO standard.

Please, can't some engineer somewhere construct a decent bike light for road use.
Many already out there.

J.
 
Please, if you can link to some good bike light for road use it would be helpful.
Gretnabikes.com | Lupine Bike Light Sets

Piko and Wilma are great. New versions are coming in the next month or so. Bluetooth remote control etc... I have the Wilma from a two years ago that was 2400 lumens max. Current one is 2800 lumens. New one coming is 3200 lumens and has bluetooth control. I typically run mine at about 1500-2000 lumens and then step it up to full bright at 2400 for descending or high speed.

Piko is 1200 and new one will be 1500. It's a tiny light and also works great on either the helmet or the bars.

Both of them, I mount them using the GoPro mount under my K-edge computer mount. Really a neat mounting arrangement.

Road Biking - Light & Motion

Light and Motion Taz lights are also great. We have the Taz1200 and like it a lot if you want a battery/light in one package.

I've used both for road riding in pretty much all conditions.

J.
 
The lupines are great lights, no questions about that. But I still don't understand how you can recommend a 3200 lumens full beam light only, for road use.
And can someone tell me why it is such a bad idea to have a bike light with a cutoff beam when you are biking in traffic.
 
The lupines are great lights, no questions about that. But I still don't understand how you can recommend a 3200 lumens full beam light only, for road use.
And can someone tell me why it is such a bad idea to have a bike light with a cutoff beam when you are biking in traffic.
Have you ever tried one? Think about what it's like when you turn on your high beams in a car on a dark rural road. Same thing on a bike and just about the same amount of light. Descending on a road bike on such a road I probably have need for more light than a car because I'm on skinny little tires.

If you don't think you need that much, then don't buy that much.

If you aim a conical light down, you get the same effect for all intents and purposes as a "cut off" light.

Just a comment on the initial post. Would you like cars to drive around in traffic with just fullbeam lights?
Of course not. But I do think it's reasonable to have as much light as a car does. We're both vehicles. A car headlight on low beam is around 1300 lumens, if I recall.

J.
 
The lupines are great lights, no questions about that. But I still don't understand how you can recommend a 3200 lumens full beam light only, for road use.
And can someone tell me why it is such a bad idea to have a bike light with a cutoff beam when you are biking in traffic.
I don't think anyone is saying that it is bad to have a cut-off beam pattern. That said I've seen really bad examples of cut-off beam patterns ( on cars ). Earlier this year the company I work for bought some of the newer Ford mini vans. One night I was asked to fill in for someone else and had to use one of the new vans. When I started driving down the road I couldn't believe how bad the headlights were! On low beam the beam pattern went about 60 ft. and then completely cut-off into total darkness. I've driven a lot of vehicles in my line of work and to date these vehicles had the worse headlights I've ever seen. It was so bad that the next day I told my boss that the new vehicles were unfit for night use. While he shrugged off my comment I later found out that the company decided "Not" to buy anymore of the Ford vans. Apparently other employees must have experienced the same issue and had spoken up about it. Like I told my boss, with the extreme cut-off beam pattern I could have a deer standing right in the middle of the road 100 ft in front of me and unless there were some other source of light to illuminate it I wasn't going to be able to see it until I was 60 ft. from it. At highway speeds that wasn't going to work.

Last night ( out of curiosity ) I took my road torch and held it in front of me ( pointing away, in front of my face ) while standing in front of a mirror ( 5ft. away ). I tilted the torch slightly downward while looking ( directly ) at the light source in the mirror. With the torch set for low I had no problems looking at the light. Set for medium ( ~ 500 lumen ) it was brighter but not blindingly so. At full power yes blinding but I'm standing right in front of the light source and looking directly at the light, something that is not normal in a real world situation. Use common sense and you shouldn't have any problems.

Also keep in mind that even if you find a lamp with a cut-off beam pattern that ( as a bike lamp ) it is still in the users control as to how the lamp is aimed. A cut-off beam pattern can still be aimed high "if" the user chooses to do so. Of course if they do that they will lose more light directly in front of them, a very bad trade off in my opinion.

Nope, give me my Gloworm X2 tilted slightly down and set at about 500 lumen and I'm fine for most road situations. The only time I would need more would be for perhaps a high speed down hill run. In that situation I would go to high or turn the helmet lamp on. At least with a helmet lamp you can point the lamp away from on-coming traffic if present. Of course if I'm on a dark road and there are no cars around I can always use as much light as I want.

Anyway, ( sorry if I ramble on a bit ) I guess what I'm saying is a cut-off beam pattern can work as long as it isn't too confining. I've never used a bike light designed with cut-off but I would think if the design were right it would be very popular with a lot of people. Just remember, just because something seems like it might be a good idea doesn't necessarily mean that it's actually going to be better.
 
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