Subscribe in a reader

Monday, September 17, 2012

Distant Early Warning

I must confess, I used to see people running blinky lights in the day time and think they were overcautious nerds. Why would they want to just waste their batteries that way? They were just plain smart, actually. Still nerds, but smart nerds. Hang on, this raises a question for me; are all nerds, by definition, smart? Is there any such thing as a dumb nerd? Help me out if you can.

Here's the thing: the more warning a motorist has about your presence, the better they can plan how to get around you. The less time they have to think, the worse their decisions become. If you could reach backward with some sort of signal to let them know you were there, wouldn't you?

Simple, right? I can't speak to other brands of tail lights, but the very popular Planet Bike Superflash Turbo really is visible in daylight when using the blinky setting.





Click image to see it on Amazon.com



I read that claim sometime before I bought it and thought, yeah, right... but after running it in the daytime and feeling like passing behaviours may have improved a little, I did an experiment in a parking lot at work and I learned two things:




1) The human eye is amazing (I already knew that... I've been thinking about it a lot lately as I review all my bike video and wish cameras worked like eyes). Anyway, I could see my Superflash blinking away in strong direct morning sunlight with my eyeballs, but video taken both from my phone and helmet cam could not. That sucked, because this post was originally supposed to be about showing the video "test".

2) The distance I used was roughly 100 yards. I could see that thing. I don't know how far away I would have had to go to lose it. Had I been driving, it would have caught my eye.

Short version: It might feel kinda stupid, but check and see if your rear light is visible in sunlight and if so, run the sucker. Early warning for motorists = better treatment and less craziness. Usually.


How Do You Use Rear Bike Lights?

 

Yer Pal,
R A N T W I C K

16 comments:

anniebikes said...

I agree. I see some who run their taillights all the time, day and night. It really does work and seems a small price to pay to stay safe. Problem is, I haven't heeded this advice, er, at least not yet.

Thanks for bringing this to "light" again. (Couldn't resist the pun.)

RANTWICK said...

Annie - Yeah, despite having come to this conclusion, I forget about half the time still. I usually remember as soon as I'm in a busier "being overtaken" situation and hit the button then (I have mine on my helmet).

Trevor said...

Seems to make a lot of sense....

-Trevor

Mighk said...

To me it only makes sense if you have a really bright tail-light. Even then it's likely unnecessary unless it's foggy, rainy, etc.

Think about relative speeds and perception/reaction/braking distance. If a motorist is doing 35 mph and you're doing 15 mph that's a 20 mph closing speed. 20 mph is about 28 feet per second. Assume 2.5 seconds of perception/reaction time (that's what traffic engineers use) and you get 70 feet. That's how much distance the overtaking motorist covers while recognizing you're there and determining what to do. Braking distance at 20 mph is less than 50 feet. So that 35 mph driver needs only about 120 feet to see, react and slow to your 15 mph. At 55 mph (same 15 mph cyclist) the driver needs about 300 feet.
The more important questions are not "Can the motorist see my light?," but "Can the motorist see me in time whether or not my light is on?," AND, "Are there things that could make me even more conspicuous than my tail-light?"

For the second question in urban areas the answer is (assuming normal seeing conditions) yes, they can see just fine without your tail-light.

But on high-speed roads where the driver needs to see you from farther away, might another treatment work better than a tail-light? Yes, either a white or yellow-neon-colored shirt or jersey would be far brighter than any tail-light, because there's this ginormous light source reflecting off it called The Sun.

Steve A said...

I only use this secondary safety measure when visibility is down, as in conditions of fog or rain. I guess I'm simply chea.., er, frugal. You Canadians, being a wealthy people, needn't bother with such things. Mighk's suggestion about high vis is great, but you can always simply turn that light on while you ride home to dig that day glo outfit out of the laundry.

Carolyn said...

I think that they are useful during the day. I wish I had one like the Planet Bike light blinking all the time while I road down the Pacific Coast this Summer, especially California. I had one on my helmet that wasn't bright enough to be effective during the day.

I don't use them during the day though around home.

On a side note, One guy had a non battery way of bringing attention to himself and his bike. Flagging tape streamed from his bike while riding. Don't know how effective that was though.

cafiend said...

I learned about the Superflash a couple of years ago on a ride with my brother. He was using a recumbent trike at the time because a fractured elbow prevented him from using an upright bike. Because he was pedaling a lounge chair down at hubcap level he had a Superflash either on the back of his seat or on his helmet, I forget which. I could definitely see it strongly in full daylight from more than 100 yards away.

My own experience with the Superflash continues experiments I performed with a white strobe many years ago. A flashing light not only draws the eye, it has certain connotations among road users. It calls for caution even more than an ugly yellow shirt would. In the early fall, when drivers seem to become more aggressive, I started using the Superflash on the section of my commute where I need to herd traffic most aggressively. I have almost been killed by a tractor trailer and more than one foliage tour bus on this section when I did not cover the lane strictly enough. I have also had drivers make radical passing maneuvers when I was well out in the lane because they consider it their right to go by me as soon as they get to me. The strong flashing light seemed to smarten them up nicely.

As these lights become more common they actually become less effective because people realize they're just attached to bicycles. I hardly bother with mine anymore unless visibility is poor. If people start getting unduly pushy I'll snap it on in daylight, but it's hardly even a daily occurrence anymore. When I commute in dusk and darkness I use it all the time when I'm on a roadway. On a side path or a very quiet road I rely on the generator setup for front and rear lighting and let the blinky lights rest.

RANTWICK said...

Mighk, as usual I think you are right on the money. I wasn't really thinking that running a light in the day time was the best way to be seen... I think of a light in the daytime as a second or third idea that comes after the more important things you raised. I was also skeptical and simply surprised that I really could see my light in bright sun.

Your points regarding bright clothing though, are really well taken as a reminder. I must admit that ever since I got some decent lights, I've thought and cared less about my jersey / t-shirt choices.

As an afterthought, I'm wondering if I have experienced nicer passes since running the light not because I'm being seen that much sooner, but because the overkill of a blinking light in the daytime marks me as somebody who is downright worried about being seen... I'm not; I only started this daytime light stuff recently and have had no problems for years. Does the light have the same kind of impact as wobbly riding? Hmmm...

RANTWICK said...

Wow, I was interrupted in writing my reply to Mighk and other people wrote a bunch of stuff! Thanks all for your quality comments. Given my great Canadian wealth, I'm sending each of you a penny for your most excellent thoughts.

drummergeek said...

I love the superflash turbo! I only use it in bad weather or at night though. Like Steve A, I'm too "frugal" to run it during the day. :)

One thing I don't like about my setup is that I can't turn it on/off while riding. It's mounted to the back of my trunk bag...

Haven't come up with a good solution for that one, so I live with it.

Ἀντισθένης said...

I often run my Superflash in daylight too, and get people trying to be helpful telling me I've "left it on". Never drivers, of course. The others I get either a chuckle or confusion when I thank them, and tell them that means the %$#@ed drivers see it too.

RANTWICK said...

drummer - I've got it mounted on the back of my helmet with a zip tie so I can reach it, but I sometimes worry it is aimed a little wrong, ie skyward or to the side.

Ἀντισθένης - going by the poll it would seem that you and I are a little special that way...

christopheru said...

I run mine all the time now - too many near misses and I want to remove the excuse that the motorist could not see me. Incidentally, the superflash is supposed to be visible day or night for up to about 1km (supposing now hills *roll eyes*). They are dirt cheap ($18 @ MEC) - I am thinking of running two of them actually on the commuter when that bike gets revved next week (wheeeee! new wheels!)

Graham said...

I've got a set of reelights permanently mounted on my commuter. They run all the time and don't require batteries.

It's great. I don't have to worry about taking them off the bike for fear of them walking. There's no worries about turning them on or off. And lastly no dirty batteries to replace.

http://waterloobikes.ca/2011/04/17/review-reelights-are-battery-free/

RANTWICK said...

Graham - Those are pretty cool! I followed the link to the site and the price seems pretty steep... no batteries to buy, but still...

I noticed that bike had Marathon Winters on it. I just bought some 700c 35mm ones for this year's winter bike. Have you been happy with them?

Anonymous said...

Mine are cheapies, fine for night, but useless during daytime. I mostly do dirt, but if I was on the road regularly then I definitely would invest in some daytime-visible lights.

Post a Comment