Yeah, I bought a magicshine clone from amazon, plus one of those diffuser lenses. Still too narrow of a beam for me. The diffuser turned an 18-inch spot into an 18x48 inch oval.

Generally speaking, if you can't see the center of your light beam about 2 carlengths ahead of you, the light is aimed too high. The primary reason that you run the light is to actually see where you are going so that you can avoid stuff on, or in, the road. If the light doesn't hit the road, you are wasting your light.

You don't want the light to shine straight down so that it is only inches in front of your wheel either since you want to see that stuff on, or in, the road before you hit it. That's a waste of your light as well.

As for being seen, if you have a light that is bright enough to light the ground, cars will see it.

This comes up over and over again. It doesn't matter how good your night vision is. If you are running lights or around lights at night, you don't have night vision. Your eyes are full of retinal...a form of vitamin A...that is sensitive to light and changes configuration when exposed to light. Your body makes it continually but if it is exposed to light, it just keeps changing configuration. Once the configuration is changed, it takes about 30 to 45 minutes to clear out of your system. Once the changed form of retinal is cleared from your system, you actually have "night vision" so you could walk across an open field without lights or see many more stars or navigate by the moon. But flick on a light and the whole process has to start over again.

But if you step out of a lighted building and turn on lights on a car or bike or street, you don't have "night vision"...good or otherwise.

I agree with your principle, so my rule of thumb is, if the top of the beam doesn't hit the road, it's too high. So somewhere in the spectrum of pointed straight down, and top ray of the beam being horizontal (touching the horizon), is where you want the light. There's no perfect place in that range, but like others have said, the point is to see where you'll be riding. The faster you ride in the dark, the further forward you need to see to avoid obstacles, thus the higher angle and more beam spread you'll need (thus the more powerful light you need to fill the more spread beam area with equivalent brightness)

Center out two car lengths (25 feet?) seems a bit tight if you have descents. I want light more than 25 feet out if I hit 25 MPH on the horrible roads I'm on sometimes. I have situations where I can move to avoid a pothole, and be trapped in a converging V of potholes, if that happens with only 25 feet of warning, I will not be able to stop in time and I'm looking at between a pinch flat and a crash.

I can bunny hop you, just not on your side. Just look away for a moment when you see bright lights, doesn't everyone do that when they are driving a car? Look into those with a pulse mode. Not a crazy strobe, but a steady light that gives a momentary flicker. Much better.

I don't know what kind of cars you drive but 2 average "car lengths" is more than 25 feet. More like 30 to 35. Honestly, my the lights on my bike at about 30 to (say) 40 feet shine further out than the lights on my truck.

Headlights
 

[QUOTE=thunderseed;19035207]So, what's the best kind of light for night riding in town?

Cars set to a standard 2" drop at 25'.
Federal requirements state headlights to be 24-54" from the ground, 39" average.
A 2" drop from 39" would be average.
My bike handlebars are 40 & 42" high.

I set the top of my beam to 34" at 22', using duct tape marker the length from the garage door to my handlebar with the rear wheel against the wall. It throws the focal point to about 30'on the ground.

Another option is to not ride faster than you can see ahead and react.

If you can adjust your lights so that you're not blinding drivers or other bicycle riders (or pedestrians) and have enough throw to ride over 25 MPH then go for it. But consideration for others and not causing them to crash comes first. As well, no matter how good your lights you'll likely not be able to see animals or kids that might run in to your path.

I agree, in most instances concerning bike lights, drivers are just complaining. I don't see them get their panties in a twist and reactionary over obnoxiously bright emergency vehicle lights, flashing neon road or commerce signs, Xenon driving lights, etc., all of which (including the standard vehicle low-beams) far outshine the majority of bike lights I've seen being used.

Which town ? what traffic conditions , what time of day are you riding? How long are you on the bike?.


Go fast you need Bright lights , There is a Brightness competition amongst manufacturers

Seriously bright battery lights will need external batteries Or the run time will be short .


Hub Dynamo Lights are my favorite since I just get on, and start pedaling. LED dont even turn them off.
(though B&M & Schmidt put in light sensors and can do that by themselves , off day/ on in dark.


I wont rehash the brand favoritism. you can look that up. this forum has archives .

and a whole electronics and such gadgets section too.



;)

Oregon does not salt roads. Cars don't die here. There are thousands of Type 1 and Type 2 Volkswagen's running around. Cars of that era, you actually had to aim your headlights periodically. How many drivers do you imagine do that? How many cyclists after removing their B&M's to go shopping at Whole Foods actually re-aim them after re-attaching them for the ride home?

More pertinent... how many seizures have you had on the MUP as a result of someone's front or rear strobe? A lot of money is spent designing those things so they DO NOT trigger seizures. You would have to be a truly exceptional case, and even then it would be difficult to prove it was the light that did it and not just that your body decided to seize for some other reason. Let it go. Flashers are here to stay. You are asking a lot of the average cyclist that they remember to shut down their flasher for the time that they are on the MUP and re-start them upon exiting.

If a driver seizes, even once, its surrender their license for two years, time. Period. Why should that be different for cyclists? Maybe because the chances of a cyclist causing grievous bodily injury to anyone else is low. The driver doesn't get to say "that's not fair, there are all these flashing lights and things... ...". Cyclists shouldn't either.

How many 'Whole wallet' Food stores do you assume there are in the State?

[MENTION=36008]Leisesturm[/MENTION], I agree that other people's epilepsy shouldn't be a big concern, but there is such a thing as using a light inconsiderately. Do you agree?

I ride a bike route daily that functions for all practical purposes like an MUP, but without the peds! I see all manner of bike lighting coming towards me but tbh I can't say that any have blinded or offended me. The 4,000 lumen HID lamps in late model blinged out Japanese and European sedans, and worse, the lifted trucks with the HID's at head height! They take my breath away. I've been behind the odd cyclist with a real dazzler of a rear flasher, but I know my own PB Superflash is nothing like that. My MagicShine 808 is usually mounted on my helmet. I take pains to keep it out of people's eyes. I've never been flashed at. The odd ped has yelled in the past but really, MagicShine type intensity is no big deal these days. Five years ago, yes, they were ungodly bright, but in 2016, not so much.

Quite a few. Gosh I can rattle off a half dozen, all in a 2 mile circle. There are also the New Seasons' and Trader Joe's' too, but I didn't want to go there. We could be here all night listing the various entertainment, grocery, dining and other retail establishments of interest to Millenials.

It's good that you are considerate. My point is that not everyone is.