Bike-light systems, Part 2: Bulbs, batteries and brand names

The Team Issue model from Nightsun  Credit: Courtesy
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The majority of bicycle lights on the road today use low-powered AA-batteries, but as with any new technology, lighting systems are steadily improving to offer powerful lights and long-lasting quality, while they decrease in price.

Sometime in the not-too-distant future, rechargeable batteries and high-wattage lighting systems, at an affordable price, will be the norm for cycling lights.

Until then, there are a few technical points that can help you understand the dizzying array of choices on the market.


Lamps, or bulbs, in the lighting system world can be divided into two main categories: incandescent bulbs, which use a filament, and arc lights (or bulbs), which use an electrical arc running through gas plasma.

Examples of incandescent lights are your standard light bulb, while arc lamps are your basic streetlights. Until recently, almost all bicycle lights were incandescent.

Many companies advertise that their systems use halogen bulbs. This is interesting because halogen bulbs, which are part of the incandescent bulb family, are actually very inefficient at translating power (wattage) to light. And, through their burn process called a "halide cycle" halogen bulbs gradually darken the inside of the bulb over time, therefore casting less light, writes Marty Goodman in an article called "History of Electric Lighting Technology."

This means you carry a heavier battery to push more wattage through the halogen to generate light. That said, most quality headlight systems use halogen bulbs durable and long-lasting because they are still one of the best options ...

... Unless youre up to date on the latest technology in bicycle lighting systems and metal-halide lamps. These are extremely efficient bulbs that emit a bright, blue-tinted light.

General Electric started to experiment with metal-halide technology 50 years ago to produce a stronger light, Goodman writes in his article. The result was a tiny mercury arc lamp that burns a metal halide salt and emits an extremely powerful light that requires relatively low amounts of power (watts).

CatEye, the first to use metal-halide technology, calls their lamp the Stadium lamp, while Niterider calls their model the High Intensity Discharge, or HID.

The lights work extremely well. Metal halide lamps are about four times more efficient in turning light into electricity than all other industry standard halogen bulb/incandescent systems; the light from a metal halide bulb approximates the color of sunlight at 6,000 degrees Kelvin, which is twice the amount given off by a halogen bulb.

While a standard halogen bulb might use 15 watts of power, metal halide lamps provide the equivalent of 80 watts of halogen light. An example of this lamp technology is the headlights on expensive sports cars such as a BMW or Mercedes, which give off a blue tint.


Batteries split into three groups: lead acid (AA or AAAs), nickel-cadmium (Ni-Cads), and nickel metal hydride (NiMHs).

Heres the quick primer: Lead acid batteries come with the cheapest systems, Ni-Cads with medium-priced lights, and NiMHs with the most expensive systems. Generally, quality equals price in the battery world.

The most common bicycle light battery those using lead acid batteries are heavy, low-power, and expensive to replace or a hassle to charge with a homemade recharging system. However, they are also the most affordable, at about $15 for a standard system.

Rechargeable Ni-Cads, with half the weight and twice the power of lead acids, are the bicycle lighting industry standard because they work well and have a long life. One downside is that Ni-Cads contain cadmium, a poisonous heavy metal.

NiMHs weigh half again as much as Ni-Cads and are even more powerful because of increased energy density, a major benefit for weight- and light-conscious cyclists; NiMHs can be finicky to recharge if the manufacturer hasnt supplied a good charger.

Batteries generally come in two shapes: deck-of-cards-sized rectangles or water-bottle size. Rectangles fit nicely in pockets or bags, but cords extending to the light can be an issue. All water-bottle batteries are NiCads, and work very well, unless youre thirsty for that extra bottle of water.

How much battery power do you really need, anyway? Power is measured by watts, so the more watts, the more power. Many systems offer anywhere from 5 to 15 watts, and some much higher.

Very generally speaking, 2 to 3 watts is good for commuting in lit areas, maybe 5 to 6 watts is needed for riding on the road in unlit areas, and 10 watts or more is needed for off-road riding at night, writes Myra VanInwegen in her article, "High-Powered Lighting Systems."

After using all those watts, youve got to refresh the batteries. Almost all re-chargeable battery systems come with a battery charger, but whether youre using lead-acid batteries, NiCads, or NiMHs, never completely discharge your batteries; that is, once the lights go yellow or dim, turn them off, cautions VanInwegen.

Even though a manufacturer might say something indicting that you can fully drain your lights, they really mean: "Until the light turns yellow or dim." Push a battery until it truly dies, and youre chancing damaging or destroying your battery through a process called cell reversal.

Likewise, dont overcharge your battery unless you have a smart charger that switches to a very low current when it detects that the battery is full. In short: Read your battery care instructions before plugging in it will last a lot longer that way.

Handlebar vs. helmet mount

One of the biggest decisions to make when purchasing a good-quality lighting system is whether to go with a handlebar or helmet-mounted headlamp.

A bar-mount light allows you to use dual-beams; while the headlamp is a single, for weight savings (many helmet-mount lights come with a bar mount as well). Although a dual beam throws more light, it is concentrated straight ahead, while a headlamp system lets you look where the light goes. (Try turning your head to catch a glimpse of something as you ride past its like staring into the void if you dont have a helmet-mounted light.)

A dual beam gives you both high and low beams, which is useful to be able to point at different angles depending on streets or the terrain youre riding.

On-road, use a headlamp to pinpoint drivers attention especially vehicles about to make a right turn onto the street in your path. Call it the deer in the headlights phenomena: Turn your headlamp directly at the cars windshield and the slow-rolling or inattentive driver of the car invariably jerks to a stop, avoiding a possible accident.

If youre mountain biking at night, by all means go for a headlamp. When navigating uneven terrain, having a light directly in your sight line is indispensable, allowing for higher speeds through narrow, twisty trails. There are those that swear by using both helmet and handlebar mounted lights, giving them the best of both worlds, high-power and go-with-sight headlights.

Lighting system companies: A sample of the bicycle lighting companies.

Best known name in the business; was present at the first 24 Hours of Canaan 24-hour mountain bike race in 1991; offers an LCD controller that displays burn time remaining on a constant basis, eliminating guessing when battery capacity will run out; offers the MicroBrute charger with an In-Vehicle adapter, which will charge a battery to full capacity from any state of discharge in five hours or less.

One of the first bicycle light manufacturers; since 1986; claims making 40-watt lights when there were no more than 4 watt systems around. Also makes lights for different applications, such as marine and police lighting systems.

Described in magazine reviews as a lighting system that gives a lot of light for your buck, Cygo-Lite offers many systems for under $100; Hey, its a light thats been on my bike and running for five years now, said one commuter about his Cygo-Lite.

Cat Eye
First to offer metal halide bulb technology with the Stadium lamp; also offers a wide selection of mid-priced lighting systems.

Sigma Sport
A German company more famous for its high-quality cycle computers, Sigma Sport also has very well-thought-out lighting systems, including a Fast-Click that mounts lights to the handlebar or stem mount and presumably work with the precision of, well, a German sports car.

Light & Motion
A company which started building dive lights, and recently branched into the cycling; innovative design include NiMH batteries, Turbo Chargers, and adjustable head lights reflectors and beam patterns. Company states that it treads lightly on the earth: Our passion is exploration of the natural environment.

Replacement bulbs: Do you have a burned-out bulb in a system that works just fine otherwise? Find a replacement at

Want to ride 100 miles? Check out our Century Challenge section

Online training diary: Use Training Bible to record your mileage and vital stats, and gear up for your next race.

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