Lights on your bike serve two purposes: they illuminate your path in the dark and make you more visible to motorists and pedestrians. The type of lights you use will depend on where you ride.
There’s usually enough ambient light to see, so your lights are primarily for making you visible to motorists, pedestrians, and other cyclists.
Comparatively low-powered lights work well for city riding:
•Coin cell battery lights are light and compact, and you can attach them to handlebars, helmets, seatposts, or racks. Due to low light output, they are best for occasional use.
•Hand-cranked generator lights mean you’re never left in the dark by dead batteries. Crank them up and go, but you’ll need to rewind them every 30-60 minutes. Even if not used, must be recharged every few months to keep the battery conditioned.
•AA or AAA battery lights are brighter than coin cell or hand-cranked options and can be run on rechargeable batteries for eco-friendliness and economy. Good for regular commuting, they’re bright enough to be seen even on sunny days. Consider running them all the time in flashing mode to stand out from visual clutter.
Consider mounting two lights both front and rear. This protects against light failure, and lets you operate them flashing out of phase with each other, so there’s never a dim micro-second when a motorist glances in your direction. Wearing a helmet mounted light in addition to your handlebar lights, lets you point a beam directly at motorists you’re not sure have seen you. But use a low-powered light and be considerate. Blinding your fellow road users is not only rude – it’s illegal and unsafe.
Away from street lights, you must light your own path. The faster you ride and the trickier the trails, the more light you’ll need. To give you time to react to obstacles, you’ll need both a wide beam and a light that “throws” a good distance.
Many riders use a combination of handlebar and helmet mounted lights.
•Handlebar lightsshould have several hundred lumens of output. Look for high-capacity lithium-ion batteries, and smart chargers that condition the battery for optimum life. They illuminate only where you’re steering, not where you’re looking or may turn, but the shadows they cast make holes, rocks, and roots easier to detect.
•Helmet mounted lightsdon’t create obstacle-revealing shadows (the light beam is along the same axis as your eyes), but they illuminate whatever you’re looking at.
If you are not going to use your light in the summer, or you park your bike over the winter, remember to top-up rechargeable batteries before you store them. The batteries may be damaged by sitting around without a charge for an extended period of time. Pull them out a few times throughout the season and charge them for a few hours. It is also a good idea to remove non-rechargeable alkaline batteries from lights before storing them, as they can leak and cause damage.