Brevet Lighting
Rear Lighting
For safety reasons, your choice of tail lights is more important than
your choice of front. Fortunately, there are good off-the-shelf
solutions. Red LED technology is pretty advanced.
Typically, commercial tail lights are powered by two AA or AAA
cells. They become quite dim toward the end of their advertised
runtimes. If you use a AAA-powered light with an advertised
30-hour runtime, be prepared to replace the alkaline batteries after
each night of riding. The runtime of an AA-powered tail light
can be extended through four nights of a 1200K ride if you replace its
alkaline batteries with LiFeS cells (sold primarily to power
digital cameras).
The minimum system I'd consider is the Vistalite "Super Nebula
5". If properly aimed, it is adequately bright. If you have
two, one can be flashing and the other left solid. Each will
serve as backup for the other. The Nebula 5 uses two AA cells;
Vistalite's "Total Eclipse" is essentially the same light powered by
smaller AAA cells.
Cateye's TL-LD600 is slightly brighter, but you are condemned to using
AAA cells. Cateye have recently introduced the AA-powered
TL-LD1000 to rave reviews on the Bikecurrent mail list,
but it may not be available in the United States in time for the 2005
rides.
The ultimate commercial tail light is made by Nightrider, but it
requires an external battery pack. If you use a Nightrider head
light, it is certainly worth considering. It is very bright.
Whatever tail light you choose it is critically
important that it be aimed correctly. LED tail lights
achieve most of their brightness by focusing all their output into a
very narrow beam. Mount your tail lights
rigidly to your frame or rack, and aim them so their beam is exactly horizontal and exactly behind you.
Test the aim by shining your tail lights onto a wall or the garage
door. The brightest spot should be at the level of the light,
directly
behind your bike. You want to be obvious to an overtaking vehicle
a mile behind you.
Don't aim the beam sideways for the benefit of a vehicle 20 yards
behind passing on your left. If the driver hasn't seen you by
then, it's too late anyway.
Don't aim the light upwards either, even if a poorly designed chainstay
mount seems to demand it. You have little to fear from overflying
aircraft.
Don't depend on a light clipped to your bag or jersey. It won't
stay aimed properly.
And whatever you do, check your brevet paraphernalia (seat bag, rack
bag, panniers, etc.) don't block your tail light. The brightest
tail light you can buy does little good illuminating the front side of
your brand new rack bag.
Reflective Gear
To augment active lighting, passive (reflective) gear helps overtaking
vehicles identify you. The brighter you appear, the more room
vehicles are likely to give you. This is what you use for the
sake of those vehicles 20 yards behind passing on your left.
A "Sam Browne" belt has two straps: one around the waist; the other
over the shoulder. Reflective versions of this belt are preferred
by European riders, but they are somewhat hard to find in the
US. They are light and roll up into a very small package.
A suitable replacement is the cyclist's reflective vest -- a
lightweight. version of the garment worn by road workers.
Your local bike shop should have these or be able to order them for you.
Reflective ankle bands (that typically fasten with velcro) can be quite
effective. Their reciprocal motion helps identify you as a
cyclist.
Finally, you can buy reflective tape or fabric, often at your local
auto parts store. Use it to liberally festoon your bike, your
clothing, your hydration pack, your helmet, etc.
Front Lighting
American riders traditionally prefer battery-powered head lights.
Most commercial bike lights are designed with the commuter in mind, not
the randonneur. They offer lots of light, rechargeable batteries,
and a
1-hour runtime -- just enough to ride to work before dawn or home after
dusk, but probably not both. To get enough runtime for an
overnight jaunt can become a technical challenge or a logistical
nightmare.
Solutions range from:
- The Cateye "Microhalogen" (2.4 watts, excellent optics, pretty
fair light from 4 AA cells. Using LiFeS cells, you can nurse a
pair of these lights through the night by alternating them periodically
to extend battery life. Knockoffs of varying quality are also
available.) to
- Overvolted MR-11 sealed-beam halogen headlamps. (MR-11 is the
nomenclature for the shape of the bulb they all use.) to
- High-Intensity Discharge (HID -- similar to the ones on
your Lexus, but the bicycle version uses a much smaller lamp designed
for medical illumination, e.g., in colonoscopies.), and lately include
- White Light-Emitting Diodes (LED -- These newest designs promise
adequate illumination and spectacular runtimes.)
While any of these headlights may be adequate to announce your presence
to oncoming vehicles, brighter lights allow you to ride faster after
sunset. Properly placed, they allow you to better see obstacles
and contribute to your comfort level
as you hurtle through the darkness.
For maximum efficiency, bicycle halogen systems run the bulb at a
voltage where it is just about to burn out. In exchange for this
efficiency you trade bulb life. In this service, a bulb which
might be expected to last 3000 hours at its rated voltage may fail
after less than 50 hours. Abused in this manner, even a 5-watt
MR-11 system will provide enough light for fast riding on good
roads. Always
carry a spare bulb or two for this kind of light!
The Microhalogen is about the minimal system, but these neat little
lights are getting harder to find as Cateye emphasize their newer LED
replacements. You can still find them, but you may have to visit
several bike shops to come up with two. (The second serves in
lieu of a spare bulb in this scheme.)
In the MR-11 arena, avoid single-lamp, variable-output lights like
Nightrider's "Digital" line. To achieve lower output, they reduce
the lamp voltage, but the efficiency becomes so low that battery life
is only slightly increased.
If you enjoy tinkering and are good with a soldering iron, a very good
MR-11 system can be put together with a special-purpose Lightbulb Voltage
Regulator to reduce, say, a 12-volt battery pack to drive a 4.7
volt lamp at 6 volts. Unlike an unregulated system, the output
will remain quite constant until the very end of the battery
life.
I used such a system on my first BMB attempt in 2000; it would last
about six hours on eight C cells (whereupon began a desperate search
for a convenience store to pay inflated prices for replacements needed
to continue the ride).
HIDs give enough light to blind oncoming cars, but suffer the same
runtime problems as the higher-powered MR-11 system. They are
very expensive, and battery logistics are a nightmare. They are
certainly bright though!
Finally, in the last year, there has been substantial progress in the
evolution of LED lights. The early Cateye LEDs used multiple
white LEDs, and despite Cateye's reputation for excellent optics, these
lights had a quite diffuse pattern. I will approve such lights,
but he will not be happy about it.
More suitable LED lights use a single 1-watt or 3-watt LED source from
Aligent (a Hewlett-Packard subsidiary). The single LED is much
easier to focus, and reportedly the 1-watt versions are roughly as
effective as the 5-watt halogen systems. Most commercial LED
systems are unregulated, but unlike halogen lamps, LED efficiency
actually increases as the battery voltage decreases, so they are able
to drain more lifetime from their batteries. These lights are too
new to give specific recommendations. If you're interested in
this sort of thing, check Bikecurrent.
European riders prefer generator systems.
They know what they're
doing.
For the 2001 brevet season, I switched to a German hub dynamo: Schmidt's Original Nabendynamo
(SON for short). I will never go back to a battery
headlight. There is no perceptible drag. You need not worry
about changing batteries. You just ride, and there is light.
I bought my hub in Germany. In the US, Peter White Cycles is the
sole distributor of these hubs, and thus it is quite difficult to
negotiate on price. Of course, to the price of the hub, you must
add the cost of a built-up wheel, but it certainly will give you great
peace of mind.
An alternative is the Swiss-made Lightspin
bottle generator. It is nothing at all like the bottle generators
you strapped to your Schwinn as a kid. This thing is quite a bit
larger. You can spin the little wheel that rolls against the tire
sidewall, and it won't coast down until twenty seconds later.
There is no detectable drag.
One catch with any bottle generator is the potential for slipping in
wet weather. In Europe, one can buy a variety of replacement
rollers, brushes, etc., that purportedly remedy this situation in
various climates. In the USA, you just have to hope for dry
weather.
The other catch with the Lightspin is that as far as I can tell, you
can't buy them!
Certainly, there is no distributor in the US. I suppose you can
buy them directly from the manufacturer, but I haven't
tried.
However, you can get one free! During the last two PBPs, the
manufacturer offered free samples to all the registered riders.
One GCC rider used his in 2003 and loved it. The manufacturer had
a booth at the finish and our rider bought four more to give as
Christmas presents. It might be worth an email to the guy to see
if you can score one, especially if you can't reason with Peter
White. As I recall, the going rate was 90 euro per Christmas
present.
Peter White sells a competing bottle generator, the B&M
S6/12. It's supposed to be similar to the Lightspin. I
don't know; I've never used it.
With any generator system, you must purchase the headlight
separately. I recommend the Lumotec. The Bisy (or the
Schmidt E6, which uses the same optics) casts a light pattern which
precisely illuminates the road from edge to edge.
I started with the Bisy, because I heard it was more focused. It
is.
You point it at the road, and you see the road. You point it at a
ditch, and you see a road. You point it at a tree, and you see a
road. You point it at the side of a building, and you'll swear
you see a road.
It doesn't waste light, but I didn't like it. The slightly more
diffuse Lumotec leaks enough light to put the road in context.
That's what I currently mount to my bike.
Mounting the Front Light
The front light should be mounted to a part of the bike that steers:
the handlebars, stem or fork. Affixing it to the headtube works
okay when you're riding fast, but during low-speed maneuvering, it
doesn't point to where you're going; it points to where you would have
gone. (This mistake is most common for recumbent riders because
there's often a lot of frame out front of the steering
bits. As a recumbent rider who's tried it both ways, I can assure
you that it's worth the trouble.)
That said, the final mounting position is a tradeoff. To maximize
your visibility to oncoming vehicles, mount the light as high as
possible (typically the handlebars). To lengthen the shadows cast
by obstacles and potholes, mount it as low as possible (typically just
above the fork dropouts).
Personally, I choose the latter approach. All but the smoothest
roads appear to me as the surface of the moon. If I steer around
the major craters, I get a pretty smooth ride. With some
experimentation, you may find an intermediate position that suits you
better.
Helmet Lighting
The bike-mounted light is good for seeing the road, but it is miserable
for reading street signs and cue sheets. For that reason, many
randonneurs mount a light to their helmet. A tiny keychain LED
flashlight is adequate for reading the cue sheet, but something a
little bigger is useful for street signs. Some of us
prefer the Princeton Tec Impact. I attach mine to my helmet with
a Velcro strap. It's a little heavy, but I can easily remove it
after the sun rises.