Front steady (unless battery low), rear flashing.

My commute bike has generator lights on steady in all conditions, front and rear. I add rear blinkie based on lighting and traffic conditions - helmet and frame mount.

My rando bike has the same lighting capability, but i generally turn the dyno lights off in full daylight conditions. I'll use the blinkies if I'm solo and I feel traffic conditions warrant extra visibility, that is if legal where I'm riding.

Steady light in front and back but if I get caught in bad weather conditions, rain, fog, I switch on flash in the back.

Flashing front only makes sense if you ride on busy two lane road where cars will overtake against you - in which case, you should keep close to road side because you can't count on drivers seeing you anyway even with your bike front light flashing. Basically, in poor visibility conditions, you should ride your bike defensively as if you were invisible to car drivers, which means you don't really need the front light, except if its so dark that you need to see where the side of the road is. But such riding is only for commuters who often have no choice, makes no sense for sport riding to go out in poor visibility conditions, never mind dark.

Flashing both sides makes sense for commuters on busy downtown city streets where you have all kinds of lights around in the evening and you need to call attention to yourself.

I ride in the suburbs of Long Island so both are flashing since they draw attention.

I don't mind pulsing lights, but strobe on the front seriously bothers my vision.

Rear, always flashing.

Front, flashing day and steady at night.

I was driving home and came up on a rider with a solid rear light, dark clothing & and minimal reflective surfaces. I think a blinking light would have made him more visible.

For regular riding at night, wear clothing that's reflective also.
On my commuter bike, I put reflective tape on the crankarms

Why do we always have to "guess" at what drivers can or cannot see? I am a driver as well as a rider so I default to what I would find most visible. It's not rocket surgery.

Flashing rear, Flashing front.

I find the argument against flashing front always presumes the light is aimed at the drivers eyes. Mine is not. It is aimed down, so the light illuminates the ground directly ahead of me. This creates a large illuminated circle for drivers to see while at the same time not blinding them. assuming the light is pointed into drivers eyes is like assuming car headlights are always used on high beam. Occasionally someone does that but its not how they are used in general.

Bicycle lights are not the same as car lights. We don't have brake lights that intensify (well a few have fancy ones I suppose). We don't have turn signals and we don't have back up lights. That argument doesn't hold water. However, whenever a stationary or slow moving object or vehicle doesn't want to be hit it uses a flashing light. Construction barriers, snow plows, maintenance vehicles. Must be something to that.

Today, for the first time, I saw a rider on a dirt trail with a solid bright headlight aimed directly ahead - in my eyes. That WAS annoying, and a little odd, as it illuminated nothing but air.

Many auto drivers do not expect flashing bike lights.
 

The first time that I saw a flashing bike, the bike was a bike/walking path. It startled me because I thought it was a motorcycle on the wrong side of the road coming towards me. As the bike came closer, I realized that it was a bike. My guess is most auto drivers do not realize that bikes have such bright flashing light. It definitely had my attention.

They are not only waving, they are giving them the one finger salute! :eek:

Federal Motor Vehicle Code makes it legal in all fifty states, for motorcycles to have modulating headlights.

I generally don't ride when it is dark or even dusk so about 95% of my riding is during daylight hours. I use a solid white front light but on the low setting. Not sure how many lumens but it's not a lot. My rear red strobe is one of those long narrow type that I attach to the seat post. I always have it on flashing.

For the purpose of giving all vehicles (including the ones being guided somewhat between the lines by someone who’s mostly texting, but occasionally glancing up at the road) behind me the full benefits of depth perception, I have a semi-bright steady light at the bottom of each seatstay, and a bright steady light right under my saddle.

Similarly, I have a pair of bright lights just inboard from my brake levers on each side of my handlebars.

err....perhaps because we aren't able to run lights of the same intensity/beam pattern as cars/motorcycles. Gimme a lamp that performs the same as a car headlamp (without the need for a 5 kg battery pack) and Ill happily not use my strobing front lamp.
At night, I also use a steady lamp........as I need to see where Im going 100% of the time.

Being on the far side of the road, my flashing front light isnt going to be too much of an annoyance to oncoming traffic, but hopefully will get the attention of those that are going to pull out from a side street to join the road Im on or to turn across it.(which Ive found does help)

Serfas makes them. Cateye makes them. I’m certain there’s at least five other companies that make them. Look for 1100 lumens or more.

I have a pair of Serfas 1200’s that last a bit over an hour on high at 0 degrees murican.

I’ve parked the bike with just one on low and walked up five blocks at the tail end of rush hour to see how much visibility they give as compared to a car- it’s a smidge less bright than one side of a common modern car’s low beam. One on medium is about as bright as a single modern Merc/BMW headlight. To light up wet pavement as much as a car requires both lights be on. They typically charge from near dead in under three hours. I would only give them my full stamp of approval if they were less fragile.

Perfect for city streets at dusk with a bunch of GOTTAGITHOMETOPEENOWWW drivers. Definitely overkill at 430am.

I’ve also got a Cateye Volt 800 and a L&M U1K that each are fine for early morning riding. Probably fine for riding between 930am and 230pm. I definitely get less people rushing to turn into me from the right with the two Serfas’ on full during RH than with those two lesser lights on full.

Flashing rear light.
I want upcoming drivers to see me.

Steady at night

Flashing during the day

Rear light flashing

Flashing front and rear, day and night.

I find that other cyclists with steady lights are hard to see against a complex urban environment, especially when there are vehicle lights.

I also wear day-glo/reflective anklets. The motion makes them 3x easier to see than reflective vests.

Bright daylight: front off, flashing rear.
Overcast, foggy, dusk, etc.: flashing front and rear.
Dark: steady front, flashing rear.
(steady rear if riding with someone close behind me).

That would be true only if it was midsummer the whole year round, with 20 hours of daylight. For those who are working 9 to 5 and still want to get some rides done on weekdays during the winter, there is no choice, commuter or not.

And what about endurance rides that may take 24 hours or more?

I wish there were some controlled experiments on this if it's even possible. I'd be interested in knowing flashing vs steady vs high vis clothing. I have never had trouble detecting any cyclist during daylight hours, even those that wear asphalt colored clothing. My belief is that with daylight lighting we are hoping to steal away the attention of a marginally engaged driver. So how that could be replicated in a controlled experiment is beyond me.

I have used a blinking/flashing rear light for over 25 years... I used to use a single D-cell USCG-approved Xenon strobe light, but now just use a 100 lum USB-rechargeable red blinky.

I used to use a steady front, but when someone pulled out in front of me < ~20' because he said he claimed he didn't see me (he was looking for a car-sized object on the 55mph State highway, and NOT a bicycle at early dawn light), I use BOTH a steady headlight AND a low-intensity white LED blinky in the front. The blinky does grab attention, but is not as obnoxious to drivers as a full-power blinking headlight.

So anyway, now I use a cheap Walmart/Schwinn button-cell white blinky in addition to my 300 lum LED steady headlight and a 100 lum red LED blinking taillight.

Front and rear flashing during the day.

Distracting them to an extent that they run over an everyday pedestrian crossing the street who didn't have the same foresight to have blinky lights sewn into their clothing?