If you are considering cycling at night or doing so bicycle tourism, then you need to be very concerned with lighting and luminescence to insure safety because you will be riding at dusk and perhaps on moonless nights. And ifyou are going to ride at night you need to have good lighting in both front and rear.
You'll need rear flashers to warn motorists and front lighting (headlights) to see the debris, potholes and road hazards ahead of you. There are several options and most of the bicycling lights now use LED lights, due to their low wattage requirements. There is a big difference between the functionality of these lights and things you need to consider.
Many of the smaller lights use AA Batteries and they only last about 24-hours of run time. Some manufacturers advertise more, but generally they base this on a flashing white strobe for the run-time, which you can not use while riding long distances. You need a steady light. Now realize that as the batteries die, you have to dispose of them and buy new ones, this can get costly and you have to stop and go shopping and that takes time or carry spare batteries which costs you stay, as you need to stay as light as possible.
Some riders like the high-tech friction lights that work off the tires, but putting a drag on your tires slows you down. These lights are much more powerful and luminescent, but certainly not my first choice. The AA battery lights are decent and there are several brands, Trek makes one which has five LED lights and has a luminescent rating of 60, most of the 3-LED light units are 40 or less on the luminescent scale, either of these works at speeds of 20-miles-per-hour or more on a moonless night. Now for riding in central twilight or as the sun is going down, they work wonderful and are legal in states that require bicycles to have lights if they ride at night.
There is another brand called Tri-Newt that has a LED light that scores 480 luminescent on the scale and has an ion-lithium battery, which Velcros to the top bar of the bike frame. The ion-lithium battery is re-chargeable, but this also means you need somewhere to re-charge it and you have to tote around the recharging unit. The cost of this lighting system is steep, $ 300-400, and the company has another similar unit that scores 200 on the luminescent scale for under $ 200. One cool option with these lights is that you can mount them on your helmet and run a cable to your water-backpack system where the ion-lithium battery is placed. I wish you well in all your cycling adventures.
Source by Lance Winslow