Help Me Choose A Headlight

Prisoner at War said:

Quoted message said:

If you do go with some mega-bright, no-optics solution, please be
courteous with it.

Quoted message said:

Some of us have encountered cyclists with those systems approaching us
on bike trails, and have experienced being blinded. Some users have
bragged about car drivers flashing their brights, because of the glare
from those systems.

...

Yes, that's a very important point you make. While I was certainly
relishing giving them motorists a bit of their own medicine with an
HID light, I also don't want my fellow cyclists to be blinded! I'm
not sure how they could be, though, seeing how they'd be at the same
eye-level as me...

It absolutely can and will happen. I've been on the receiving end, on
a short cut-through bike trail in our town. I remember desperately
trying to shield my eyes and close one eye to retain a _little_ night
vision. It was ugly.

Quoted message said:

Not sure how I'd prevent their being blinded, anyway: I couldn't
predict it, could I? But I'm sure the two HIDs I'm considering have
some kind of optics which should mitigate such circumstances. They
better, anyway, for $600!!!

Wrong. They won't. Or more precisely, I'll be amazed if the beams
are anything other than circular - that is, sending exactly as much
light up as down. For some reason, manufacturers of $600 HID lights
(or $200 MR-16 lights) can't replicate the optics of a $20 Cateye
light from 1990.

The only way to NOT blind an oncoming cyclist with a no-optics high
power light, is to point the light down in front of you. But then
you'll find you've got a super-bright patch of road close in front of
you, it's reflecting back and ruining your night vision, and you can't
see very well at all. This is why I don't like the crude-optics mega-
lights.

Before you shell out the cost of a bicycle on an excessively bright
light, try this: Borrow an ordinary, good quality bike headlight.
Try a Cateye Halogen Micro-II, for example, if you can find one (the
pre-LED model) or any decent generator light. Put it on your bike,
have a friend ride your bike toward you, and see how conspicuous 2.4
watts of halogen light really is.

I've done this with dozens of other cyclists, in night lighting
workshops. I've never had any of them say "That's too dim to be
safe."

If you want to up the lumen output, that, fine. But be responsible,
and don't think you've got to look like a supernova to be noticed.

Quoted message said:

So which one do you recommend?

I recommend a generator light. If you don't like to generate your own
power, I recommend a generator lamp powered by your own rechargeable
battery pack. If you want twice as much light, either put in a more
powerful bulb into the lamp assembly, or mount two of them.

- Frank Krygowski

Gary Young said:

Steve Gravrock said:

On 2007-05-02, Tim McNamara <[email hidden]> wrote:

Quoted message said:

Quoted message said:

The light source needs to be
low- fork crown height or lower- to maximize its usefulness. Most
battery powered lights are designed to mount above the handlebar or-
even much worse- on your head.

Quoted message said:

It seems like there could be a market for something that allows
handlebar-mount lights to be mounted low on the bike. Does anyone make
anything like that?

Minoura makes a clamp for that purpose:

and you can find them here @ tinyurl.com/3yccs4

Prisoner at War said:

Anyway, a good reminder, your post. I almost never feel the need for
a light, but all club rides require them (except the anarchist Time's
Up! rides -- hooray!), and, in keeping with my nature, if I get
something I'd like to get the best. ^_^

I'm glad to see more night rides by clubs. Some clubs are very explicit
as to the brightness of lights that are required, but any available HID
light should be sufficient, usually the minimum is a 6 watt
quartz-halogen headlight and some sort of an LED or xenon tail light.

With the HID and MR series of lights, you don't really have to worry
about blinding other cyclists, as the optics on these are very precise.
On some of the sealed beams the light is more of a flood pattern, and I
wouldn't use the 25 watt version in traffic as it could be annoying.

SMS said:

Prisoner at War said:

Anyway, a good reminder, your post. I almost never feel the need for
a light, but all club rides require them (except the anarchist Time's
Up! rides -- hooray!), and, in keeping with my nature, if I get
something I'd like to get the best. ^_^

I'm glad to see more night rides by clubs. Some clubs are very explicit
as to the brightness of lights that are required,

Oh? How do they measure brightness?

Quoted message said:

but any available HID
light should be sufficient, usually the minimum is a 6 watt
quartz-halogen headlight...

"Usually"? I'd like to see some citation for that.

Quoted message said:

With the HID and MR series of lights, you don't really have to worry
about blinding other cyclists, as the optics on these are very precise.

Quoted message said:

From what I've seen, the optics on HID and MR lights are very precise

only in that they don't throw light out the back! They do throw a fog
of light out the front, _roughly_ in an eight degree (fairly typical
spot) or 30+ degree (fairly typical flood) radially symmetrical
pattern. IOW they throw as much light up as down.

Compare this with the optics on, say, my car headlamps, my motorcycle
headlamps, or my bicycle generator headlamps. All these direct less
light upward, since more light is needed downward onto the road. The
cutoff plane is easily apparent. They use the light output
efficiently.

Remember, light going upward toward other road users travels directly
from your lamp to their eye. It doesn't need to be as powerful as
what goes down. The downward light must hit the road, where some gets
absorbed and some gets scattered. Only a small percentage bounces
back to your eye to show you the road.

You need bright light down, much less light up. Radially symmetrical
optics don't do that.

- Frank Krygowski

Prisoner at War said:

Not sure how I'd prevent their being blinded, anyway: I couldn't
predict it, could I? But I'm sure the two HIDs I'm considering have
some kind of optics which should mitigate such circumstances. They
better, anyway, for $600!!!

In reality, the optics on the higher end bicycle lights are excellent.
It's not a wild unfocused beam such as on the old 2 D cell battery
headlights of the olden days. The quartz-halogen lights are typically
using MR lamps, which are very good optics with matched, mirrored
reflectors.

Most bicycle and motorcycle HID lamps also use MR11 and MR16 type lamps,
as it's become the super-standard for high-end lighting.

One of the big advantages of the MR system is that the bulb is aligned
precisely with the reflector at the factory. One problem with the lamps
where you replace the actual bulb is that you have to align the bulb by
trial and error (not even possible on the cheap lamps with threaded
bulbs, and a hassle on the higher end lamps with a bulb that can be
rotated for proper alignment).

Look at HID lamps on vehicles. If aimed properly, the low beams don't
blind you. Contrast this with some of the crappy daytime running light
implementations that use the high beams at half-brightness, and blind
you even though the lights are not really all that bright.

Quoted message said:

So which one do you recommend? Looks like the NiteRider is a winner.
Funny how I can't really find reviews of these guys online. I've seen
only one "real" (i.e., useful, with a good photo) review of the Light
& Motion product, but none yet for the NiteRider (which is newer,
though).

Anyway, a good reminder, your post. I almost never feel the need for
a light, but all club rides require them (except the anarchist Time's
Up! rides -- hooray!), and, in keeping with my nature, if I get
something I'd like to get the best. ^_^

(Yes yes I know "the best" is a semantically ambiguous term....)
(Yes yes, I know, "

You really have to look at them to evaluate them. Do any have a metal
mounting bracket to the bike? How rugged is the wiring and the switches?
How much will battery replacement cost? How much is a replacement
lamp? Most of these systems use the MR11 Welch Allyn HID lamp, which
costs close to $90, and you definitely want to have a spare. There will
soon be a flood (no pun intended) of lower-cost replacement HID lamps
coming in from Asia, you can already see them on the manufacturer's web
sites.

Richard B. said:

SMS said:

Prisoner at War said:

I'm wondering whether to get the Light & Motion ARC Li-Ion Ultra HID or
the NiteRider Moab HID/LED.

--Snip--

Quoted message said:

Again, this site is primarily to help people construct their own
high-performance lighting systems. It's been expanded over the years to
include information on other options, including a section that explains
the pros and cons of dynamo systems at
"http://nordicgroup.us/s78/dynamo.html".

You might want to add this link to your website, it is full of information
about LED related components and devices, some of which which may be
directly used on a bicycle or converted to bicycle use. There are also HID
and fluorescent related articles.

http://ledmuseum.home.att.net/

Uh, I don't think I'll link to it. All sorts of browser warnings come
up, and the site is even more amateurish than my own!

SMS said:

Prisoner at War said:

Not sure how I'd prevent their being blinded, anyway: I couldn't
predict it, could I? But I'm sure the two HIDs I'm considering have
some kind of optics which should mitigate such circumstances. They
better, anyway, for $600!!!

In reality, the optics on the higher end bicycle lights are excellent.
It's not a wild unfocused beam such as on the old 2 D cell battery
headlights of the olden days. The quartz-halogen lights are typically
using MR lamps, which are very good optics with matched, mirrored
reflectors.

The optics of MR lamps are excellent for their primary intended use:
track lighting, to properly display paintings on walls, or to give
supplemental or decorative lighting inside houses and buildings. For
those applications, you want a soft, even, radially symmetrical beam
pattern.

The optics required for road use are entirely different. Park your
car in front of a wall and examine the shape of the headlight beams on
the wall. Rather than a radially symmetrical beam, you have a
precisely tailored beam shape. The most notable feature is the
horizontal cut-off plane, with bright light below that plane (to land
on the road) and dimmer light above that plane (to prevent blinding of
other road users). There are legal requirements - at least, in many
countries - governing the shape of the beam.

Quoted message said:

Most bicycle and motorcycle HID lamps also use MR11 and MR16 type lamps,
as it's become the super-standard for high-end lighting.

AFAIK, motorcycles are subject to the same legal beam requirements as
other motor vehicles. Certainly, my BMW has a beam shape that's
tailored as precisely as my car's lights. I seriously doubt any
radially symmetrical HID lamps are used as original equipment on
motorcycles, but I'm willing to look at properly cited evidence to the
contrary.

Now it's true that aftermarket light sets have no road-tailored
optics. Those are the ones installed by irresponsible hot-rodders,
the ones that blind oncoming traffic.

Quoted message said:

One of the big advantages of the MR system is that the bulb is aligned
precisely with the reflector at the factory. One problem with the lamps
where you replace the actual bulb is that you have to align the bulb by
trial and error (not even possible on the cheap lamps with threaded
bulbs, and a hassle on the higher end lamps with a bulb that can be
rotated for proper alignment).

Statements like that make me wonder about SMS's experience with
lights!

Bike generator headlights use flange-mount bulbs. The flange-to-
filament distance is precisely controlled. When replacing a bulb, the
flange sits against a precisely placed shoulder. The shoulder has a
protrusion, and the flange has a matching notch, so the bulb fits only
in it's precise orientation. No trial and error is necessary. In
fact, it's not even possible!

Quoted message said:

You really have to look at them to evaluate them. Do any have a metal
mounting bracket to the bike? How rugged is the wiring and the switches?
How much will battery replacement cost? How much is a replacement
lamp? Most of these systems use the MR11 Welch Allyn HID lamp, which
costs close to $90, and you definitely want to have a spare.

IOW, add $90 onto the already exorbitant cost of the HID set you're
considering.

Through all this, I think it's good to remember that motorcycles
travel legally up to 75 mph. Their headlights are designed for such
speeds.

Using that light output for a bicycle is as inappropriate as using
motorcycle wheels on a bicycle.

- Frank Krygowski