Update! I sold the L&M lights after a few months. The Lupine offerings are far superior, and that remains doubly true even as of February 2011.
As the days grow shorter and/or the weather is unusually hot, I’ve extended my riding time into dusk or night. I tried using some handheld Surefire military-grade flashlights such as the L4 Lumamax, the C3 Centurion and the M6 Guardian, surely the most amazing flashlights I’ve ever used by far, with outstanding beam patterns, pyrex windows, and light and durable hard-anodized bodies. But burn time is limited to an hour for maximum brightness (or 20 minutes for the 500 lumen M6 Guardian [or 1 hour for 250 lumens]). Don’t compare those numbers to cheap half-assed imitations—the beam quality and lenses on these lights are second to none.
Buying advice: if you regularly use a flashlight, run, don’t walk, and buy a L4 Lumamax—it will last a lifetime and easily outshines a 4 D-cell standard flashlight while weighing a measly 3.4 ounces. The L4 Lumamax easily fits in a jersey pocket, and is a superb backup light if you think you might miss sunset by an hour or less. It is also more than adequate for modest-speed trail riding—just velcro-strap it to your helmet and carry a few extra (and very lightweight) CR123 batteries, which can be had for about $1.00 each in quantities of 40. It burns for 1+ hours at 100 lumens, then degrades in brightness gracefully for another hour or so. Other models at lower brightness and longer burn times might be a better choice for slower sports, such as nighttime hiking. If you’re into extreme brightness, the M6 Guardian with the 500 lumen bulb will obliterate the beam of those half-assed million-candlepower lights you can buy for your car’s cigarette lighter—I verified this personally. Then there is also the 3500-lumen HID Hellfighter for your car, or if you really want to freak out homicidal motorists, strap one onto your bicycle (bring a backpack for the car battery). Come to think of it, that would be really fun once in a while for certain rednecks I’ve encountered. The 50-caliber machine gun is optional, and might be questionable in some liberal areas, such as California. Besides, mounting it to a bicycle would be difficult.
But for riding where there is real darkness and/or cars, and/or speeds up to 35 mph, a serious light is needed, so I’ve acquired two Light and Motion bike lights—the ARC LiIon HID ones. (HID = High Intensity Discharge; the HID bulb produces about 3X the light of a halogen bulb for the same wattage). The ARC LiIon burns at 13.5 watts (675 lumens) for 3.5 hours or 10 watts (550 lumens) for 4 hours—plenty of time for me. For the hard-core, there is also the ARC LiIon Ultra, but the only difference is a larger battery that can burn for 5 hours at 13.5 watts or 6+ hours at 10 watts.
Alternative lights of similar or possibly better quality exist, such as the Lupine Edison 10 ($799) or Edison 5 ($669) [reviews: 1, 2, 3]. Another high-end alternative is the Supernova P99-E or SX-14 ($1000) . The dual-beam P99-E can burn at 28 watts (!) for 2 hours, or 14 watts for 4 hours, and looks to be a superbly built light—if $1000 sounds good to you. There are also other HID lights, such as those from NiteRider. Some models require a water-bottle style battery, which I find quite limiting because I lose the ability to carry water in the bottle cage, and it restricts use to a bicycle (unless you enjoy a large bottle in your pocket). So I prefer the models with flat battery packs that stuff into a jersey pocket and/or strap to the bike frame.
I was able to buy two (2) Light and Motion ARC LiIon units for about $729—about the price of one Lupine Edison 5, for a total of 1250 lumens, vs the 900 lumens of the Lupine Edison 10/5 and roughly the same lumens as the Supernova P99-E, but with 3.5 hours of burn time. One light, cable, battery and mount weigh about 520 grams, so two of them weigh about 4 1/2 pounds. Are the lights worth it? If your life isn't worth much to you, buy a cheap helmet (or go without), a cheap and dim light, and stop reading this blog!
The ARC LiIon light throws a beautiful beam— a bright center area with a fairly large but less bright area around it. I find it works extremely well for road riding. 20-25 mph even on a curvy downhill is no problem with this light. With two of them, speeds up to 35mph are possible when the curves straighten out—they're that bright. I avoid such speeds however, as it’s still hard to spot sand or gravel and a hazard around a corner is always a possibility.
Why two lights? Because in spite of their tremendous brightness, the front wheel points in the direction of the handlebars , not in the direction of the road! This doesn’t matter on a straight road, but on a curvy one it’s a big deal as the light will nicely illuminate a tree to the side of the road, but the curve ahead remains inky black.
I mount one light on the handlebar to illuminate the immediate area from the bike forward, and mount the other light on my helmet, which lets me illuminate anything I can swivel my head to look at. This is incredibly useful for turns, for forcing cars to pay attention, for scanning for wildlife, etc. Yet the light on the handlebar is always providing light right at the front of the bike, in case a pothole suddenly attacks out of nowhere.
Still another reason for two lights is that you can carry one light (lamp) and two batteries. The major cost of HID light systems is the battery (often 60-70% of the cost), so it makes little sense to buy an extra battery alone. A Light and Motion ARC LiIon with two batteries yields 7 hours at 13.5 watts—enough for even the hard-core night rider. Alternately, it allows combinations: 1 X 10 watts, 1 X 13.5 watts, 2 X 10 watts, 2 X 13.5 watts, or 10 watts + 13.5 watts. I also means that if a bulb or battery fails, you have a backup system.
How do vehicles respond to this setup? Vehicles approaching from the front apparently see something very bright, and generally dim their headlights right away. Vehicles approaching from the rear carve a nice wide arc around me. I actually feel safer than in the daytime, where many homicidal motorists seem to enjoy cutting too close for comfort. Still, a drunken driver is always a risk, so I pay close attention as a vehicle approaches (this is a daytime risk too).