Tips & Tricks: Auxiliary Lighting for Your Motorcycle

With daylight hours growing shorter as winter closes in, you’re more likely to find yourself riding at dusk or after dark. The headlights on most new bikes are outstanding compared to those of only a decade or so ago, but no matter whether you’re in traffic on a busy highway in broad daylight or on a deserted two-laner in deer country at night, more light is better than less. Adding a pair of driving lights or highly visible spots can help you see and be seen better than even the best stock headlight.

There are three basic types of auxiliary lights, says Brandon Westphal, sales manager at Big Bike Parts, broadly defined by the job you want them to do. “What we call driving lights throw a narrow beam of light farther down the road than the headlight,” he says. Driving lights give you more time to react to obstacles in the road like potholes or debris that you wouldn’t see as soon if you relied only on your headlight. 

“Spotlights act like floodlights,” Westphal says, “throwing a broad spread of light ahead, illuminating more of the shoulder of the road than the more narrowly focused driving light.” And finally there are fog lights. “The idea here is to throw a low horizontal beam that’s wide and close to the road surface, making it easier to see roadside ditches without being aimed so high as to blind oncoming traffic that’s already having a hard time seeing through the fog.”

Halogen bulbs do a great job in stock headlights, but swapping one out for an LED changes what Westphal calls the “photometrics,” or how the light source bounces light off the headlight’s reflector. The bulb and reflector are designed to be used as a pair, and changing one or the other throws the photometrics out of whack. But auxiliary lights are designed from the start to use LEDs, so the photometrics are optimal right out of the box.

Wesphal says there are other reasons LEDs rule for auxiliary lighting. “The latest LEDs are small and light,” he says, “and the technology is evolving fast.” Because smaller lights weigh less, they’re less susceptible to the jarring of rough roads and more durable than halogen bulbs. LEDs are also very directional–the light goes right where you want it, and not much of anywhere else.

But perhaps the best reason to go with LED auxiliary lighting is that LEDs draw very little power from the bike’s electrical system. “That’s important on small bikes whose charging systems might not be too robust, and on larger bikes with a lot of electricity-gobbling add-ons like heated grips, a radio and hookups for heated clothing.”

Where to mount auxiliary lights varies with the purpose and the available locations, but some states prohibit locations that place them higher than the headlight or less than a certain height from the road surface. Aiming them so they light up the road without blinding oncoming drivers is important, too, and might need to be adjusted on the fly with the addition of a passenger or a lot of luggage that raises or lowers the angle of the front of the bike. Another legal matter concerns DOT approval. Wesphal says that wherever possible the auxiliary lights sold by Big Bike Parts are DOT approved, which removes one potential problem if you ever get pulled over by a picky trooper. “It’s also handy if you’re in a state that requires regular vehicle inspections,” he adds.

His final piece of advice: “Don’t cheap out on lighting. Amazon and eBay are full of inexpensive no-name LED auxiliary lights that don’t work as well as quality products that cost a little more, and they’re almost certainly not DOT approved.”