I'd be interested in people's opinions of the best front and rear light modes for warning drivers of your presence. I was out on my road bike this evening and it has a small Moon front light - don't know the exact model but it was given free to me by the bike shop that I bought the bike from, and it has a couple of steady modes and three flashing modes.

One of the flashing modes is 'epileptic seizure' strobe! It annoys the hell out of people but is easily the most noticeable by both pedestrians and drivers. However, because of its potential to cause discomfort to people, I avoid using it. I usually leave it on one of the slower flash mode.

What light modes do you use for your front and rear lights assuming you're riding at dusk or night with street lighting?

I hate flashing lights. IMHO - car drivers have a hard time identifying your position and direction when your light is off half of the time.

A lot of bicycle lights now have modes that are on all the time but vary the intensity to help get you more attention. I think that is a much better idea than flashing on and off.

I pay attention to what works best when I see a cyclist while I'm driving my car. A reasonably low lumen slow blinkie, and hi-viz shirt always registers quickly and easily without being annoying. Excessively bright lights and unusual blinkies, while very noticeable, cause me to stare at the cyclist in a bad way, and I'm a big believer in target fixation. I don't like using front lights, except to illuminate the road - I prefer to control the risks in front of me.

I find that a lot of bike lights, particularly rear lights, have a very focused beam that almost resembles someone pointing a laser pointer at you! I wish there was more thought out into light diffusers to spread the light pattern more evenly.

I use my brightest flashers in daylight in traffic. They aren't bright enough to blind anyone. I've seen enough drivers notice me and slam on the brakes when they were about to pounce in front of me from a parking lot or intersection. It works well enough.

At night I'll change the mode or lights. My helmet light is only 300 lumens and very directional from the front but with good side visibility. I'll continue using the flashing mode in traffic. My rear helmet light is only 20 lumens on red so I'll leave it on flashing mode. Just bright enough to be seen from a distance at night. Between the blinking and normal head movement it helps drivers see me. I've noticed other cyclists much more readily at night when they use similar low power helmet lights.

For night use on my bike mounted Cygolite Hotshot I'll change the mode to either a lower intensity blinking mode, or a slow pulse that peaks at maximum output.

When riding the multi-use path or cycling with groups I modify the lights to suit conditions -- less output, aimed lower.

Front and rear blinking work very well, I've even had motorists, at a light, thank me for my efforts to be more visible.

When driving, I'm not bothered by the flashing light of other bikers during the day. In darkness, it's a little annoying but tolerable.

I use the bright flashing light both front and back for most rides I do which are in the daytime. The low flashing light for long rides where battery life is an issue. It also is the recommended setting by most of the various agencies and law enforcement around here. No specific laws, though many think it law.

I do know the the brighter than heck strobes they are putting on law enforcement and emergency vehicles lately make if very unsafe at twilight and night time while it is raining. At least to me it does.

Maybe because I ride and when I drive I'm looking far down the road but I see cyclists long before I see any lights.

I saw someone today with a taillight that has upper and lower part alternating on/off. So it looked as if his bike or the light was bouncing up and down. It's quite visible, tells the driver you are moving and they can tell how far you are (like in the case of solid lights) yet no annoying flashing at all. (Does anyone know what brand/model it is?)

I have a bright daylight flashing mode front light. The rate of flash is about once a second. I find lights that have faster flashing modes are too distracting. After dark, though, the flashing front light destroys my ability to see the road and I switch to steady mode. My strong light is on the bars. I also have a less bright light on the helmet so that I can turn my head and aim the light down side streets. I've considered adding a fairly wimpy flashing front light for night riding so that drivers can more easily distinguish me from another automobile.

IDK about UK seems the German products* comply with their laws and cannot flash so they don't..

As far as judging the perception of others seeing those lights, havent there been several univirsity studies on those by now?

I'd research the various research studies to answer your own question.. but you can sit back and just read these few opinions ..

anecdote : I have a hub dynamo and wired head and tail lights *B&M, but I dont live in London or even Portland.

I can use the Pavements, a bike lane and traffic lights on my mere 1/2 mile trip home from the pub



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I'm a big believer in the cygoliye steady flash. It's a steady beam with random flashes. The light never turns off. This is true for both front and rear. Currently I have a metro 1100 lumen front light and a hotshot pro 150 lumen rear. They've worked wi fearfully for me and last very long as well.

I have a Cygolite metro on front flashing and a Cygolite Hotshot on rear. Both on steady flash. Front light very bright and easy to see even at a distance. I see it reflecting on traffic signs 100 yards out. Irritating? Maybe but I want to be seen. The motorists are already irritated that we are even out there. The rear is a bit directional and I believe more attention getting at a bit of a distance rather than close up, so that it spreads a bit.

Note; This is daylight riding, I don't generally ride at night. But on rare occasion right at dawn or dusk and I run the front on continuous at those times.

It may be annoying to drivers but the reality is that a cyclist's vulnerability trumps their annoyance, IMO. If drivers really want to be annoyed, try getting sued for wrongful death, or charged with some level of a homicide or manslaughter for killing a cyclist. And then there are the psychological impacts that come from killing. So my/your increased visibility is to the benefit of both rider and driver. Nobody wants an accident or can afford the consequences.

FWIW, with respect to epileptic seizures, in most states drivers who have epilepsy are required by either their doctor or individually to notify their respective DMV. Usually they have to be seizure free for 6 months to a year to get a drivers license. I think this is very much a peripheral issue and more of a boundary condition.

Based on that, for daylight riding, I use the brightest sharp edged on-off flasher I can find for both front and rear. Right now that's the Bontrager Flare 800 lumen light in front and either the Bontrager flare in back or the Cygolite Hotshot 150. FWIW, the Bontrager Flare R seems to have great optics and does about the same with 60 lumens as the Cygolite does with 150 lumens. Bontrager has a better mount.

J.

Flashing in daylight, solid in the dark.

My rear light is the Garmin Varia Rearview and that adjusts the flashing based on approach speed and proximity of vehicles behind me. It appears to work very well in terms of driver behaviour. I think I need to sort out a decent front light. On my hybrid I have a Lezyne Deca Drive 1500XXL. This is a very heavy and very bright light, to the point that people walking along paths facing me have to cover their eyes. It literally temporarily blinds people. I've tried pointing it down to light more of the road, but it's still too bright and distracts other cyclists too.

Hence, I think I will replace it with a 'better' light that is a better balance between seeing the road ahead of me and also not blinding others.

I feel that one of the dangers of very bright lights is that people can't actually see you on your bike, nor judge how far away you are. All they see is a bright light.

triple flash 100% of the time

As far as flashers, my opinion is that distance is not a problem. In particular, the flashers draw attention to the cyclist, then the driver can see the whole cyclist (as long as the light isn't a blinding light). I'd avoid running daytime lights at night. I followed on on my bike once, WHEW!!!! Yes, you want to be seen, but it doesn't help to blind the person approaching you.

I've added a reflective rear triangle (slow moving) to one of my trailers, and need to consider better reflective markers on my gear. I believe this augments the lights at night.

Personally I don't run daytime lights on my regular bikes, although I can understand the arguments. I do try to use bright clothing. I've been experimenting with a trike, and do run the lights during the day on that.
Perhaps a little too focused of a beam, but I think the idea is to take a relatively dim light source, and focus it in the direction of most danger (straight back).

The lights should, however, also have some side visibility. My headlamp has a ring of LEDs around the outer edge (they should have blanked out those upward ones). I run the forward light Plus the ring in the city, then turn off the ring when I get out to the country roads for better night vision.

yeah but steady flash is mighty hard on battery life

yeah but you know what's hard on actual life? gettin hit by a car... (totally kidding).

i know that there are real impacts to battery life with that mode and i dont have a real solution for people who have long commutes. mine is quite short so luckily for me, i can use that mode without regard for when i last charged my batteries.

Yesterday, i crossed a bucket list item off of my cycling check list - i rode around in NYC all day. i know it isn't a huge deal but it's something i've always wanted to do. i remember seeing that the triple flash mode is the one that lasts the longest so that's the one that i chose to use all day. for the front i used a Bontrager Ion 100r on the random flash setting. when it got dark though, i did switch the tail light to the steady flash and used my cygolite metro 1100 lumen on medium. worked out fine for me.

If you're in dense traffic or high speed traffic, the seizure-inducing flash pattern may make sense, and people are not going to be close to your light while looking at it head-on. On the other hand, if you're going to be on a bike or pedestrian path, you'll be better off with a gentler pattern or no flashing. Cygolite headlights have a mode called steady-flash which has a constant beam at medium intensity and a flash (at about one per second) on high. This is not terribly annoying to face, as I've seen riders with this while on the bike path. The bike path is narrow, so I'm looking at oncoming traffic at a very acute angle. The aggressive mode is annoying and unnecessary.

I do most of my rides on my commuter bike which has dynamo powered lights. The headlight doesn't flash at all. This is OK for me, since I'm mostly on the bike path, and I don't spend a lot of time where I have to grab people's attentions aggressively. Other people have different needs.

Daytime, a 1 to 2 hz fast flash, like 50ms on, 500 to 900 ms off would be my choice. NOT a seizure mode. just bop,bop,bop. Very short.

Nighttime I like the Cygolite with 500 lumens constant, and then a 50 to 100 lumen bop over the top of that. Cygolite does a 2 or 3 beat squirt, then a second of just the normal light.

-----------!!!-----------------!!!--------------!!!

Like that. The beats are very fast, like they all happen in 0.1 second and then rest for a second or maybe even 2 seconds.

My goal is never to be annoying, but unfortunately there are some drivers who are so oblivious that to be just noticed by them, I have to cross the line into annoying to others. It's unfortunate that the drivers who I like are the ones I wind up bothering.

in traffic, strobe front & rear. aim appropriately

Anecdotally, the drivers that tell me they really like my bright flashing lights are the ones who have also respected me on the road.

I only learnt about day time light usage this year. Initially I was using my 600 lumen light on flash but then read here about how annoying bright flashing lights were and that it was bad cycling etiquette. I did notice some looks from other cyclists and pedestrians. So I switched to a cheap front light as my day time running light. Nowhere as powerful. I have it on fast flash and pointed straight ahead. I checked it out by walking about 25-30 yards away and I could see it blinking. So I figure it's adequate. But what if it's due to the bias of knowing to look for a blinking light?

At night, I keep my front and back lights on solid and have tiny silicone wrapped blinky lights on my helmet.