Flashing rear light enhances driver perception of cyclist ahead

as a motorist (& occasional cyclist) I would far prefer to see a flashing light. I am mostly in rural areas so if I see one bright steady light coming towards me I don't know whether its a car with one defective light (therefore needing to create more space in good time to pass each other) or a cyclist. Likewise when I am coming up behind a light on my side of the road, it could be a cyclist, a car or a trailor being pulled by a car/tractor.

Rural roads are narrow, often have very poor demarcation and bad verges with deep ditches. Flashing lighting is the best. It almost always means a cyclist.

Agree with many here on cyclists in black clothing with absolutely no lights at all. Its terrifying when you come right up behind one at the last minute on an unlit road.

I actually almost stop when I see one single light coming towards me anyway so dont worry. In the country you need to drive carefully. I always give cyclist space and overtake into the opposite lane when clear (on bigger roads). I am cyclist myself.

a flashing/strobe front light when approaching from behind can be very blinding to drivers, especially when viewed through mirrors.

Its also harder to determine how far away the bike is, since the brightness of such lights can vary hugely. Add in some rain and wet mirrors and you end up with a mess.

I have often thought that bikes should have different colours than cars, to immediately distinguish them from vehicles. Bikes dont act like vehicles, so the sooner you can make other drivers aware that the thing they see is not another vehicle the better. Spotting a blue light (for example) in your mirrors would immediately tell a driver that its a bike, that it will not be in the driving lane but in the cycle lane and that they need to be aware when turning left.

Its probably less important for the rear light, but I wouldnt have an issue with having a distinct rear colour also

We should take the same approach with drivers presumably? The one or two cars I see on every winter commute with no back lights because the idiot behind the wheel doesn't know how their DRLs work should be seized and crushed. The many drivers driving with one or two broken brake lights, one dodgy headlight, one rear cluster not working should all have their cars seized and crushed too?

I don't want to go down that road of talking about reflective clothing (I appreciate the point you were making, just don't want to drag things off topic)… but for me it still all comes back to a lack of enforceable legislation around lights. I'm not saying it's easy to achieve (anyone can say they had lights, but they were stolen when they locked their bike up… pretty hard to steal a car's light bulbs!), but if there were clear, unequivocal guidelines around minimum (Lux/ Lumen) during certain times of day, a German style law regarding beams, and clarification around use of flashing lights, at least then things would be universal. We'd all get used to a certain type of light & light out put and I think we'd adapt pretty quickly to being able to judge distance and whether it's a cyclist or not.

I've often been tempted to stop on the N11 and flag down a cyclist just to ask them about their rear lights/ front lights because they've been so good. I can pick them out from about a kilometre away and despite their strength, they don't blind me. Plenty of times I'll assume they're a motorcyclist, the lights are that good. Like you, I've no idea what I look like on the bike in the dark… I'd need to give my bike to someone and ask them to spin down the road and back in the dark.

If we had solid guidelines (and I'm not talking about an article, however informative and well researched, on a cycling website) around lighting, I think it would resolve a lot of issues around hi-viz. As long as you were following the lighting guidelines then it would just be a personal choice as to whether you wanted to double up on lights, wear hi viz etc.

Until then I'll probably continue with low output ancillary front & rear flashing lights on the urban/ suburban sections of my commutes.

Inevitably the Gardai who are massively under resourced won't enforce it effectively in the same way that they don't enforce mandatory tyre treat depth requirements etc. on cars effectively. But I don't think that's something that should torpedo the idea of looking at regularising road bike lighting. I'd have to check with Germans as to how effective their legislation is - obviously there's nothing to stop German's buying non-compliant lights from online marketplaces, but I think if it becomes an accepted norm, the number of people actively looking to bypass it diminishes with time.

Yeah, who knows. I just know that lighting standards are an absolute mess on the roads. But I don't agree with the previous poster who suggested that there's general non-compliance by cyclists (I've actually noticed an improvement in the number cycling with lights now). Aside from no-lights (which is sometimes just down to lack of care and battery dying), my bugbears are (a) lights that barely function (in the past typically ones where the batter was almost dead), (b) lights obscured by backpacks, luggage and (c) lights that blind me - these IMHO are mostly the high powered front lights… the rear strobe lights don't so much blind me as bring on a headache!

I suppose, as a cyclist, it comes down to how you would like to see cyclists illuminated on a dark night in an ideal world. Just spit balling really.

Agree they draw attention sooner.

The distance question is based on frequency of flashing, the higher the more difficult, hence strobe speed is a no no. For divilment I wondered whether there was regulation for frequency of an indicator light on a car. Indeed there is, 60 -120 flashes per minute, so the same setting for a bike light shouldn't bother anyone nor affect their distance judgement.

Funny you should mention Germany. I was there last week and even though most of the pedestrian crossings don't have a button, I rarely had to wait more than a minute for the green man, even crossing busy 6-lane roads. Usually I was waiting 20-30 seconds. Frequently the pedestrian crossing was green even when there were no pedestrians around. Unlike here, the pedestrian lights will go green when it's not possible for vehicles to come through.

If Germans had to put up with the crappy pedestrian crossings that we have, they might be a little less law-abiding.

EDIT: btw, flashing lights on your person are permitted when cycling in Germany.

Like they did with the phone charging cable? I like the idea, but I guess there is a large range of shapes and sizes in lights, and they also get mounted to quite a diverse range of points on the bike, or the person. Would be nice to have the option of getting extra brackets with the light for a minimum extra price, for people who move lights between bikes.