raybo

I am planning a ride that includes the French Alps on roads with tunnels. I normally use just running lights. But, I've purchased a very bright headlight for use in the tunnels.This is the one I bought: https://cycletorch.com/product/shark...light-set.aspx

When I ride around San Francisco, where I live, I like to use a blinking headlight to increase my visibility. The Shark 500 is many times brighter than my current front light and I wonder if it is a good idea to use the Shark 500 (mostly to test it) as a blinking light on my training rides. My concern is that it is so bright that it might cause problems to/complaints from people coming toward me who have to see this extremely bright light as they approach. I know I don't like it when I have to ride toward them!

Marcus_Ti

Cars routinely run 2,000 to 8,000 lumen lighting setups. Your piddly bike lighting setup is still many times darker than any oncoming car.

Further...depending on the weather-particularly in a dark downpour 500lm is barely going to be enough to see imperfections in the road.

Happy Feet

On strobe mode just point it down a bit, that way it's visible but not directly blinding.

Paul Barnard

Whether it's bothersome to other road users depends primarily upon the aim and whether it's a wide or a narrow beam. I have a 400 lumen adjustable beam light that if I pointed it into your eyes on narrow beam, it would temporarily blind you.

CliffordK

It is hard to say. One thing about car lights is they've been designed to shine at the road (especially on low beam which also directs the beam away from oncoming traffic) for nearly a century.

Most bike headlights, however, are simply flashlights with a round beam. And, to get good view ahead, one has to point them at the horizon.

Some brands are trying to do better now with shaped beams. Get the light where you need it.

I also find the extremely small point-source of bike headlights very disturbing to look at.

So, with a flexible handlebar mount, I simply point the light downwards when I'm in traffic, or approaching a person on a bike path. That pointing it down also helps notify a pedestrian that they've been seen and acknowledged.

I don't like a full flash mode for headlights, except for certain dusky situations, or in emergencies (spilled my cargo on the road).

I did have a light that would do a solid, with an interrupted flash that wasn't nearly as annoying as a full strobe. I think it was my dice light.

I currently have a fairly bright headlight, but generally use it at the dimmest setting, especially since I don't want to burn down the battery too quickly.

Marcus_Ti

Mostly about distance, and aiming. 400 lumens is nothing at 300-500ft....although it is hard to say, because lumens is a unit of flux and not brightness..,..and moreover a poor lense can negate a high-lumen rating.

For reference even dim (by any modern standard) H11 55W car headlights are 1,200 lumen....9005 HB3 halogens are "only" 1,800 lumen. Car headlights can go 4X that per side per lamp. And even then-IF it was pointed at a driver at such a distance to annoy a driver...the driver should not be staring into the light but away from it. At least my local DMV driver's manual says as much...and we're practically in the stone age here without any emissions/safety/equipment testing.

TimothyH

500 lumens really isn't all that bright.

It certainly isn't "too bright" for road use.

Use it and don't worry about it.


-Tim-

CliffordK

Oh, from riding my bicycle I've made a few realizations.

Riding with a very dim headlight. Ok for the most part, but one's eyes get dark adapted. And, then get blasted with high beams, and one is completely blind.

If I ride with a brighter light, then I'm not as much dark adapted, and don't get as much blinded when a car comes at me with high beams on.

Plus, cars respect bright lights much better than dim lights.

The one rule with riding blind...

DON'T RIDE TOWARDS THE LIGHT!!!

Focusing to the side of the road helps a lot, but only if there is a fogline.

Those roads without a fogline can be quite dangerous when one is blinded.

It is hard to say how much light is needed. I've seen bikes with dim headlights/taillights, and they really don't catch one's attention as much as a good bright light... Without blinding other road/trail users.

If you have a "Daylight Taillight", then step it down a notch at night.

Tourist in MSN

In a tunnel, depends on if there are lights in the ceiling or only the lights from vehicles.

Presumably there are light in the ceiling, thus a weak flasher or medium strength constant on beam would be plenty.

If however there were no lights in the ceiling, it would be like riding at night and at night a car driver that sees a flashing light can't assess distance as they have no depth perception on a flasher. I used to commute through a large college campus as a car driver and at night there occasionally were cyclists that thought they were safer with extremely bright flashers, but they were in fact very unsafe when they are blinding all of the traffic that is coming towards them. But in a tunnel it would be worse if only a few minutes before the car drivers eyes were accustomed to sunlight and they suddenly are in near darkness staring at a very bright strobe light.

The point being that you want the car drivers to see you and know where you are, that is enough. You are doing the right thing by asking this question.

acantor

When I cycled over the Alps, I found it unnerving to ride through tunnels, even with flashing lights on. I waited for gaps in the traffic, and then rode as quickly as my legs would carry me.

That was 20 years ago. Bicycle lights are much brighter these days. Maybe excessively so. As an occasional car driver, I have come to view super-bright bicycle lights as potentially distracting. The lights draw attention to the cyclist, which I appreciate; but some bicycle lights are almost blinding in their intensity. That's not good. As a driver, I want to notice cyclists and be able to predict where they're going to be and when; but I don't want afterimages burned onto my retina!

I like the idea others have expressed: use bright flashing lights, but aim the beams downward. As cyclists, we need to find a balance between being visible and not causing unnecessary distractions to other road users.

If I were to ride through tunnels in the Alps today on a bicycle bejeweled with modern lights, I think the experience would be just as freaky. Sharing narrow, winding roads the huge trucks, fast cars, and noisy motorcycles was NOT a highlight of my cycling trip to the Alps.

BobG

I rode through the two consecutive tunnels into Val d'Isere with an old fashioned generator head light of the '80s and a Wonder leg light. The tunnels were lit from above but I found the only safe way was to wait at the entry until a motorist agreed to escort me through the entire length from behind. That said, I found a crazy cyclist on Street View relying on just his reflectors! ...

indyfabz

Here is the light given off by my Planet Bike Blaze 500XLR in total darkness. It did allow me to see the shadowy figure of what turned out to be a giant porcupine heading straight for me, but not in enough time to get out the camera before it veered off into the bushes.

rm -rf

500 lumens is about the minimum I'd want to use. 1000 lumens or more is better for me.

Usage:
Daytime: blinking, pointed straight ahead. Blinks are usually "high" lumens, but very short duration. The battery lasts a long time. The flashes catch driver's attention even at noon sunlight.

Sunrise / sunset: blinking if the sun hasn't set yet. This time of day is when I really want the blinking -- drivers can get glare from the setting sun.


City streets at night: I use "high" most of the time. There are darker areas between street lights, bright car headlights, and well-lit areas.

Dark country roads: I'd probably use the half power 250 lumens setting for a slower cruising speed, then go to full power on faster sections. (500 lumens isn't enough to go full speed on downhills.) My eyes adapt to the darker conditions.

Other drivers or riders:
Aim the light downward more if it's practical.

Tunnels: take off your sunglasses!!

mev

For what it is worth, on my commuting setup I have two 700 lumen Cygolite lights.

Part of my route is a narrow road without side roads and sometimes speeding traffic. On that stretch of road, I'll have one light in steady mode illuminating the road ahead and the second in flash mode more straight out. I have yet to have a "complaint" flick the lights the other way. When I'm not on that road and going through more small neighborhood roads I'll turn down the flash.

A few years ago, I was cycling to work at 4am (*) and as I was passing entrance of an apartment complex, a car came barreling through, blowing through the stop sign onto the road. Fortunately nothing worse than giving me a fright. However, also a reminder that my front light pointing forward doesn't project as much as a car headlight pointing forward. After that I went to a second light and occasionally putting it on flash mode and occasionally putting it on my helmet so I can "sweep" into those side roads. However, I also avoid that particular apartment complex now.

So I'm not sure your light would be too bright. Whether to use flash mode, I'd look at local laws and norms.

(*) Time zones and India engineers...

raybo

Thanks to those who responded for your comments and insights.

djb

I have taken to angling even my rear blinky downwards a bit, so as not to be overly annoying to a driver. Even as to me as a cyclist, and as a driver, there have been times that a flashing bike light has been annoying to me, so I make a point now to angle both my lights downwards a bit.
I still feel my rear blinky is doing its job of making me aware to a rearward oncoming car, and I commute often in the dark.

my front light, which I use in blinky mode as Im in the city, is on my helmet, and as Mev mentioned, I put it on my helmet to be able to "sweep" towards an oncoming car from a sideroad, and when I made the change from handlebar to helmet, I noticed an immediate almost total reduction of a side coming driver NOT noticing me.
To me its completely natural to turn towards a sideways coming car, and I take the view that they do not see me always, and it has happened numerous numerous times where its immediately clear to me that they did not notice me until I turned my head towards them, and my blinky is then noticed--you can tell the way a car will suddenly brake, as soon as the driver is aware of me , thanks to the helmet mounted light.
Cars at stop signs, or an oncoming car that is clearly about to turn left in front of me, being able to "aim" my blinky, up down right left, exactly where I want it, is a clear clear advantage, no matter the power of the blinky or steady light.

again, this is for an urban setting, and I am lucky that I can stick my light onto the visor of my helmet, as the light is one with a flexible attachy thingee made to go around handlebars and reattach to the body of the light , and I can fit this flexible rubbery part through a vent hole in my visor, AND the light itself nestles perfectly onto my visor.

if it werent for this, I would have to have a light that goes onto a mount, which I would have to attach to my helmet.

as it is, its easy for me to remove or put on my blinky white light, which has a steady mode also--but of course, limitations in light time and brightness compared to the lights mentioned, and mine would not be ideal for a total darkness commute each day.

fietsbob

Point yours downward to not contribute to what you don't like in others ..

I bought German made Busch & Muller designed headlights ..
https://www.peterwhitecycles.com/b&m.php

they have the LED facing downward towards the reflector..

and So, have a beam pattern with a cut off , directing it towards the road, not the trees..

which a reflector, like a flashlight, with the light source in the center , will do..



My Koga WTR came originally with a B&M 4D toplight senso .. using 2 AA
it had a tunnel mode in senso .. left on it was off in the daylight on at night
and when entering a tunnel . it had a half second blink rate ..








..

Brittney

You can get a beam bender, a bit of plastic lens to adjust the angle of the light, car headlights have similar optics to put each light in the right place
https://www.ebay.co.uk/itm/Wide-Angl...frcectupt=true

You could probably make many from a square of fresnel lens if you're that way inclined
https://www.ebay.co.uk/itm/Credit-Ca...p8O-LjDTs-n_vg

djb

makes me think of driving a UK car in France, and the guy who brought it over bought these little stick on fresnel lens thingee at a gas station specifically for Brits in France so that their lights would shine more to the right, rather than the left as they are designed for, to shine towards the side of the road more, but driving in France would be shining too much into the eyes on oncoming cars.

was very weird driving a right hand car on the side of the road that I was used to, but from the "passenger" side.

dvdwmth

I have one of those double lamp cree chinese lights you can buy on amazon. Its very bright when its on full. I was testing it out in a park and I could hear voices in the shadows saying "what in the **** is that" as I rode along the path. Even my department store usb chargeable bike light is bright enough that I've had people flash their high beams at me when I have had it angled up. I'm fairly certain that at the right angle these modern led lights can impair the vision of oncoming drivers.

I generally conduct myself in as considerate a manner as possible when I'm one a bike because there is a great deal of animosity toward cyclists in Ontario, where I live. Since we are all rather vulnerable out there is probably wise for all of us. Luckily its not so bad in my smallish city but Toronto, my former home, is bat **** crazy with the tension between bikes and cars. I once had a guy in a car tell me I had brought a knife to a gun fight. He had a three year old in the car with him, observing the whole discussion.

tcs

Simplistic comparisons of one light source to another rather break down, do they not? I certainly wouldn't want to look into a 75-lumen laser beam.

At the same lumen level, this (all too common) cycle light beam shape



is more likely to be annoying to oncoming road users than this one:

Doug64

You might want to check if blinking lights on your bike are legal. In some European countries blinking red taillights are illegal, but I'm not sure about blinking front lights. IMO a steady bright front light would be my choice.

Marcus_Ti

Simplistic comparisons are all one can really do. Not even in car headlights are foot-candela specified AFAIK. And lumens (flux) is a terrible unit for the job. And there are no units/specification for beam dispersion, nvm beam shape, nor projector/reflector efficiency--nor will you find a manufacturer specify it.

A 75 lumen laser is equal to about 10 milliwatts...which by laser standards is quite dim. Due to the light being intense, and collimated, and not tapering off much over normal distances for humans, still dangerous (above 1mW really is). For lecture purposes and safety 1mW is recommended, but due to manufacturers sexing-up their lasers and underrating them, many "1mW" lasers are actually 1-20X brighter than that.