I always use lights at night, and in daylight on public streets. I add to-be-seen lights to my helmet because bike mounted lights are often hidden from the view of any vehicles that aren't immediately adjacent. I want to be seen above the rooflines, particularly when turning against traffic, or when the bike lane design invites right hooks.
The only times I don't use lights in daylight are on deserted rural roads or the MUP. But I'm planning to add a much brighter daylight-visible red taillight for some rural rides where I pass somewhat busy or tricky intersections. Just to give drivers a little more notice.
But in daylight a hi-vis yellow or orange helmet, jersey or vest probably stands out as much as lights. Particularly on overcast days. Took while for me to appreciate this but I noticed it over the past year when I could see other cyclists and joggers from a long way off when they wore hi-vis clothing. So while I don't like the color, I recently added a hi-vis yellow windbreaker and long sleeve jersey, and plan to add a couple more. I already had a cycling rain jacket that's mostly bright blue but has hi-vis yellow sleeves, and I noticed it's very visible when I loaned it to another rider recently when the weather suddenly turned chilly. She was much more visible during that night ride. I'd already been carrying several snap-on springy reflective bands on my bike frame for my ankles and wrists, and every little thing helps.
Originally Posted by
kingston
Have you ever ridden behind someone with a blinking red tail light? It's annoying. Have you ever ridden past someone on a bike path with a blinking headlight? That's annoying too. I never use blinking lights because I think they are annoying. I won't ride with people who insist on using lights during the daytime and frequently pass other riders for the sole reason of getting in front of their annoying tail light. I don't use lights at all during the daytime because they are totally unnecessary.
Depends on the light design and placement. In dozens of nighttime group rides over the past year I've encountered only two red taillights I've found unnecessarily bright and annoying. I probably should speak with the owners because we see each other often. They probably don't realize their lights are much brighter than necessary for nighttime use, but would be appropriate for daytime. In fact one I saw last week was so annoying I found myself sprinting ahead of the guy to avoid being behind him, but we swapped positions several times and, yup, that intermittent superbright white/red strobe pop was way too much for nighttime use. He's a good guy and probably doesn't realize how bright it is, because he's not the kind of guy to deliberately annoy anyone.
But that's only two out of hundreds of other red taillights I've seen. Most simply enhance visibility but aren't distracting or annoying.
In headlights the main problem I see is aiming the lights directly ahead on the MUP. While that may not be a problem on ordinary streets in traffic, it's blinding at night when passing shoulder to shoulder on a sidewalk-width paved path, or slightly wider gravel/chat trail.
I always tip my headlight downward, using my front tire's shadow as a gauge for an angle that lights up the path well enough for me to see without blinding oncoming cyclists. I've gotten off my bike and walked around the front to be sure it's a reasonable compromise.
I've noticed my recently acquired Light & Motion headlight has a much broader coverage than my Serfas. The Serfas is partially shaded by the squared off shape of the barrel around the lens, so there isn't much spill. The L&M shotguns light into the trees and sky. It could use a lens hood over the top, like the optional hood for some Busch & Muller lights, to confine the beam to the road. I'm planning to cut an old black plastic 35mm film canister to fit as a hood.