My first experience with bike lights was back in the day of Eco-Challenge. We would ride through the night on our mountain bikes, through all types of terrain, and would need strong, reliable lighting. Back then, the choice of our team was NiteRider. The very strong light was connected by a cord to a battery pack, which held (I believe) four or six D-cell batteries! It weighed a ton, and it was placed in your water bottle holder.
Talk about progress! Today, there is a great variety of highly efficient, cost-effective, and super easy-to-use lights for your bike. As many of us are riding early and late in the day, we have come to appreciate the need for a front light that can help us see what's ahead ... as well as be seen by cars approaching, cars coming in from the side and cross streets, as well as driveways and such.
In this regard, we are only looking at front lights for this review; but, obviously, one must also have a bright rear light to be highly visible by cars traveling in your direction.
What to Look For
From Mark LaLonde of Planet Bike: "Choosing the right head light for your bike can be a daunting task. There are a lot of different lights out there, for a bunch of different purposes. The first question you'll need to ask yourself when choosing a light is what do you want the light to do? Are you looking for a light to see with, or to be seen by motorists and other cyclists? How much do you want to spend? Do you want to use rechargeable batteries?"
I would add run time and ease of attachment (and detachment).
How Do You Measure Brightness?
The standard measure of brightness is "lumens." For example, the very simple, straight-forward NiteRider "Mako 1 Watt" is rated at "100 Lumens;" while, their higher end "MiNewt.600 Cordless" is rated at "600 Lumens." The latter would be significantly brighter.
However, when considering the light emitted from a bike lights, one should also consider the "distribution" of the light.
"A very powerful light that shines directly in the horizontal plane acts a spotlight, but does not actually illuminate any of the terrain surrounding you," says Torsten Abel, professional triathlete and fan of the "Nova Star" (which can emit up to 540 Lumens).
Liz Weiss, marketing manager at Cateye, adds: "The 'beam pattern' and different modes will help ensure a cyclist is seen in the dark, fog, etc."