It isn't, but it's a very useful side effect.

Extending battery life is one of the main reasons I run my tail lights in flashing mode, on the rear rack and back of the helmet. I usually run the flashers day and night and on long rides they need to last several hours. Battery life is equal to visibility in my preference for flashers over steady red rear lights. And my spare red LED is a slow flasher only.

For the front light, it depends on the situation. I prefer flashing white in city traffic since there's usually enough ambient light to see the road at night. But I'll switch to steady when I need to see the road. I'm convinced from seeing drivers notice me in heavy traffic that the flashing white light gets their attention and prompts them to pause before leaping in front of me from intersections and parking lots. I keep the helmet mounted light tipped downward a bit so it's not in anyone's eyes unless I tilt my head back and look directly at them - which is also very effective as an attention grabber.

I use flash for the rear because I'm not too concerned about drivers judging my speed by the light. In the front I use a steady light on my bars, and a flashing light on my helmet, and that has been working well for me.

Does the speed of the flash effect the battery life?

If it has equal on and off time then it shouldn't matter what the flashing frequency is. 50% on and 50% off in any given length of time.

If the flashing on time is the same but the off time is varied to get the difference frequencies, then a slower flash will yield longer battery life (less on time in a given length of time).

Did you know that modern, state of the art toilets use 1.5 gallons of perfect drinking water per flush? If you have an older toilet 3 gallons ain't rare, and up to 7 gallons wasn't unheard of. Here in California I'd say if it's yellow, let it mellow.

Not at all. That's the standard "pulse mode" for Light & Motion headlights. It also yields the best battery life.

I was flashing this morning. It's really foggy here, but not foggy enough to get get some drivers to turn on their lights. I had one light on solid and another on flash on the rear, with 3 flashing in the front for today's ride in.

All German and Dutch dyno lights -- that is, the lights you probably want, if you're a daily commuter -- are required by law to be non-flashing (from what I've been told, the reasoning is that only emergency vehicles are allowed to have flashing lights there. Makes sense.).

As for me, I've got a steady B&M dyno light on my rear rack and a blinky on my helmet. My wife has the same B&M dyno lights plus a Torch helmet with integrated flashing lights. I'm an LCI; when we did our training course, we looked at dozens of different setups, and it was clear that if you want your light to be visible, you should mount it higher on your body. So: helmet- or backpack-mounted lights are a good supplement to dyno lights.

ew, hope you have something to control the smell. My 5 year old sometimes forgets to flush after going pee and it makes the bathroom STINK!

Toto and other toilet manufacturers are going to 0.7 GPF, and even less than that for only flushing #1 . I got to tour the Toto manufacturing facilities in Atlanta and it's actually pretty neat some of the stuff they're doing.

It was super foggy this morning, some of the thickest I've ever seen. I just happened to come across a cyclist (extremely rare around here) while driving my car, just after a 4-way stop sign intersection on a 55-MPH highway crossing a 45-MPH rural road. Since I was still relatively slow from turning at the intersection, I had plenty of time to react to him. He had a light on the rear, but it was very dim and not flashing. I couldn't make out the light at all until I was very close.

A combination of BRIGHT steady and flashing lights are really important in fog as thick as it was today.

interestingly enough, I have a bontrager brand of tail light that does have a steady, steady with flash, and full flash modess. I recently checked on my visibility and found that if I have it on steady with flash mode, the steady part of the taillight is so strong that I can't see the flash part...

[MENTION=71944]e0richt[/MENTION], that just means your flash's intensity isn't sufficiently greater than the intensity of the steady mode. I don't know if that matters, but I guess it means you're wasting power for a marginal effect.

My main commuting bike has two tail lights, one steady and one flashing. This way, I hedge my bets as to which works better. I might be wasting energy, too, but it's not much.

From my observation, bright, solid lights are better and less annoying. They look more like vehicle lights, especially when some cyclists use two bright solid front lights on their handlebars. The main reason I use flashing taillights is to save power, and I usually have at least another solid taillight at the same time. For front light, I can't even stand it myself. I use a strobe light that has only flood and no throw for being seen (it's mounted where the handlebar and stem meet so it's blocked from my own eyes ), and a bright light with good throw to see (and being seen).

I flash AND steady (two lights front and two back). I've written it here before. You cannot judge where a cyclist is just by the flash. Yes, the motorist knows there is a bike there, but when they get closer they cannot tell exactly where. I've used the Coast Guard experience as an example. They might see your man overboard flashing beacon, but once they get close they cannot see you very well (so they recommend a steady light in addition to the strobe).

Coincidentally a fellow approached me in the grocery store parking lot a couple of nights ago to ask about my helmet flashers. He wants one for walks with his wife in their rural hometown. They wear reflectors but said cars don't seem to notice and still pass too closely even when there's no traffic and plenty of room to go around.

I often see folks walking with their dogs in the evening and many of them do wear some reflective bits - bands, strips, dog collars, etc. But with my bicycle headlights I find them hard to see unless the light is pointed right at them. The headlight on my helmet is relatively directional, compared with the less bright but non-directional front light I used to use. The less bright, non-directional light was actually more effective for seeing reflective surfaces - people, signs, vehicles, other cyclists.

I've always flashed on the rear, but tonight sold me on the front.

Got a new job that extended the commute from 4 miles to ~11 with half on surface streets. Ran my Magicshine clone on the front on flash. People who would normally pull out from left-side streets in front of me stopped way ahead and waited for me. It was obvious they couldn't tell how far I actually was from them, but it got their attention where with a steady headlight experience showed they would have pulled out and cut me off.

Depth perception be damned, I'll take what gets their attention.

Deleted comment. Just noticed you were talking about nighttime.

I used a blinky on yesterdays ride. It was a cool overcast day (and it's winter here)... NOT the weather when motorist might be expecting a cyclist to share the road. I also use a blinky in high traffic areas. I think this adds a tiny bit more safety to my ride... at times.

But much of "flasher" use seems close to superstition. Like... I rode yesterday with a flasher... and I wasn't hit and killed so they MUST be keeping me safe.

In reality... a drunk, drugged, distracted and confused motorist (or cyclists themselves) cause many of the fatal accidents we try to prevent with a flasher. And I've yet to see any evidence that the flashers sober-up drunks (or stoners), or causes someone to not text, or teaches a confused motorist the local roads and/or traffic laws.

I had bicycled to a local street event with mixed crowds and cars and thinking ahead... I put a flasher on the bike I had decided to take. I felt much safer and cars did seem to notice me sooner and gave me a wide berth. I was very happy with the results... then I realized I had forgot to turn the flasher on. I wouldn't put too much faith in a blinking light.

That all got started by Everybody Have Fun Tonight by Wang Chung...and I had to read this to make sure it wasn't about trench coats.

I'm more and more leaning toward constant mode for both front and rear lights.

On the Greenway when two cyclists were riding in sync next to each other in the dark, both with bright front light in constant mode, from distance it really looks like a vehicle approching; OTOH another cyclist with even brighter front light but in (annoying) flashing mode, was much less alarming to me, because I knew it's just a bike.

As for taillights, from my observation, provided the taillighs are bright enough, the constant mode is no less noticeable than flashing mode, and it moves with the bike/cyclist at any given moment; whereas flashing taillight is invisible half of the time, and the movement looks intermittant and unconnected, so harder to follow. That is unless one uses several flashing taillights at the same time which compensate for one another's "off" interval. And flashing always has that annoying side about it.

So I think the most power-saving way without losing visibility is to use, say, 3 tailights, whether all flashing or at least one constant. Imagine 3 or 4 flashing taillights, it's pretty much like a big solid light. If using a single taillight, maybe solid mode is the way to go.

If it's daytime, I'm flashing both front and rear. On the front, even a small flashing light, like a Blackburn Flea, has significantly reduced the incidence of motorists turning in front of me. The slightly larger Performance Axiom (rebranded Moon) has more reach. Once it's dark, I run just a steady front light (a bright Light & Motion), but at dusk I run them them both, and keep the steady light on low so it doesn't wash out the flashing one.

I like to have two lights in the rear: a flashing light to get noticed and a steady one to be localizable. (I don't bother with the steady one during daylight, which means that when it gets dark I always have at least one rear light with a full charge.) In theory, my DiNotte Quad should serve both purposes, because the flash runs on top of a steady illumination. In practice, I think the DiNotte flash is just too bright at night, so I run the DiNotte in steady mode on my seatpost, and an Axiom 60 in flashing mode down low on my seat stay. In that position, it's very visible from afar, but doesn't blind people as they are passing me.

FWIW, bright flashing lights can cause me to temporarily lose my vision. It's called an ocular migraine, or migraine aura - I'm not sure exactly, but if I look at the sun by accident, or into the flash of a camera, or yes, even a really bright bike headlight, I could lose about 20 - 50% of my vision for about an hour. It's incredibly annoying and potentially dangerous when I'm on my bike, but really it would be on me to pull over. I'm not sure how common this is but I just wanted to point out that some people are sensitive to bright lights, whether flashing or not, and I think it's something that should be considered.

Also, I have a sister with epilepsy, and have never seen her have a seizure that was triggered by flashing lights. I think that while it might have some basis, it would require a lot more than a bike light.

I generally prefer solid tail lights for the reasons that have already been mentioned, but often switch to flashing to extend the batteries. Particularly when there are long dark sections where I will encounter few if any people. It doesn't make a whole lot of difference either way IMO.

EPA standards for WaterSense certification is 1.28 gpf, 1.6 gpf is the old 1992 standard. Having replaced two in my home in 2013 and two in Cape Cod this summer, I can affirm that the $160 toilets available at the Blue Apron or Orange Apron bigbox as well as Amazon, specifically the Kohler Wellworth and American Standard Cadet 3's work very well.

BTW, I flash beginning at dusk. Sometimes it is just a knog light, sometimes a 3 bulb LED, depending on which bike.