Bike Lights Exercise: What Do Yours Look Like?

[bobco85]

Here’s the thing: I don’t think most people actually know what their lights really look like from a distance. Since there’s a lot of disagreement about whose lights are more effective for them versus dangerous/blinding for others, let’s do something constructive here.

Note: this exercise works best with 2 people (the other person can hold the bicycle straight up). You will need a somewhat powerful flashlight for this.

1. Find a dark section of trail or other paved area that has low/no lighting (make sure it is a safe area, too).
2. Turn on the bicycle lights on your bicycle that you typically use for night riding. If you wear lights on your helmet and you’re with a buddy, have them wear your helmet with all lights and reflectors on.
3. Set the bicycle so it is standing perfectly straight up as it would be when you are riding. Rest it against a pole (or have a buddy hold it upright).
4. Walk 20 paces (approximately 50 feet) forward from the front of your bicycle and turn around to face your bicycle.
5. Turn your flashlight on and take note of how well you can see your bicycle and the area around you.
6. Walk towards your bicycle and take note of how the lights appear to you. As you approach, is it difficult to see anything else?
7. When you get back to your bicycle, repeat steps 4-6 except walk in the opposite direction from the rear of your bicycle to test your tail lights.
8. Repeat this process at other times of day (dawn/dusk, midday, etc.), during a bright day in areas that are shaded (they will appear much darker in comparison), and even at different angles (from the sides, diagonally from behind like a driver would be when passing a cyclist on the road, etc.).

Try this out and report back on this thread how it looks. At the very least, I hope this will raise some self-awareness of one’s effect on others if not help people notice any adjustments (light angle, position of reflectors, etc.).

[mstone]

Couple of points:

1) as a driver I find pedal reflectors are the most visible thing on most bikes, and this test regime won’t show that at all. (In the best case they’ll be static instead of moving up and down, in the worst case they’ll be perpendicular to a following light.) I can’t think of a good way to test this statically, so take it on faith and just put on pedal reflectors.

2) 50 feet is way too close–less than the reaction time of a driver going 30MPH faster than you. The difference between a button cell LED and a set of reflectors bouncing back a car’s headlights at 300 feet is huge. I think too many cyclists don’t grasp this and don’t understand how important reflectors are on the road, because they can see the little LED themselves when they’re close to it in the dark.

[Judd]

When Komorebi and I took the League Cycling Instructor class we did a similar exercise. We had had classmates ride down the road for about 100 yards or so to observe how well our lights, reflectors and clothing were visible to the rest of the group.

Good suggestion Bobco.

[infinitebuffalo]

@mstone 179962 wrote:

2) 50 feet is way too close–less than the reaction time of a driver going 30MPH faster than you. The difference between a button cell LED and a set of reflectors bouncing back a car’s headlights at 300 feet is huge. I think too many cyclists don’t grasp this and don’t understand how important reflectors are on the road, because they can see the little LED themselves when they’re close to it in the dark.

FWIW, DC law requires headlights be visible from at least 500 ft; rear reflectors must be visible from 50–300 ft, though reflectors may be substituted with taillights, which should be visible from 500 ft. (WABA bike laws guide, quoting DCMR 1204.2 & 3.)

[bobco85]

Come to think of it, it’d be great to be able to test lights/reflectors in a setting where one could see their bicycle/clothing from a variety of distances and angles. My post was originally based on the argument in the Missed Connection thread about flashing/strobe/steady lights and how they actually look to others, so that should explain the smaller scale, the idea being to be able to put yourself in someone else’s shoes in looking at “you” at night.

That said, I don’t see anyone actually doing this exercise. Get out there ya lazy bums!

[n18]

Close one eye for 5 minutes so it adjusts to the dark, you know; like a pirate, then look at your light. You need to go slow while doing this test, because Ninjas are hard to see. l did a similar test and my light was brighter than I thought it was. Apparently, just seeing the trail with my light, which is kind of a spotlight, was enough for my eyes to adjust away from darkness that other trail users have adopted to.

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