When the sun sets, dusk begins. Dusk may be worse than darkness for a cyclist. Reflectors only work if a light hits them, so drivers who wait to turn on their lights will not activate the reflectors, if any, on your bike.
Reflectors are nearly useless for visibility anyway. The most effective ones are on the pedals, where their motion attracts the motorist’s eye. Because these reflectors often get broken or obscured, replace them with reflective leg bands you can carry in your pocket or seat pack until you need them.
A solid tail reflector can be mistaken for someone’s driveway marker. A white one on the front will similarly get lost in the clutter of many roadside backgrounds. Wheel reflectors can only be seen from the side. If you’re crossing a motorist so closely that you need him to slow down to avoid hitting you, you’ve made a hideous mistake. At night, never, ever, ever believe that someone sees you. Make sure you have lots of room to maneuver.
Dusk even swallows the power of car headlights. Your best defense is to use blinking lights to attract attention.
With a good blinking tail light or two you can be fairly safe from drivers approaching from behind. A little blinking tail light fits handily in pocket or pack along with the reflector leg bands.
Not much will help you with oncoming traffic. A headlight bright enough to command respect would require a battery weighing about 50 pounds. The best accessory for safe night riding is to have a Humvee escort in front and behind.
Darkness ends my commute long before the weather would. It has nothing to do with seeing the road. Rechargeable lights give plenty of light for that. I just can’t count on being seen by motorists.
When I had no car and commuted in a more urban environment I did ride all year, at any hour. I also had a commuting bike permanently equipped with generator and battery lights. The terrain was fairly flat, the distances 12 miles or less. I was younger. There were fewer drivers. There had been fewer movies glorifying sociopathic driving habits. There were no cell phones. The average age was a lot younger. You decide if it's worth it.
Night riding can be fun if you don’t have to get anywhere on a schedule. I will occasionally take a night ride with no tail light and no reflectors, on very quiet roads. As soon as I detect the faintest glimmer of an approaching headlight or sound of an engine I dive off the road, douse the headlight and freeze.
A loop that might take just under an hour in daylight may take 15 or 20 minutes longer because I ride a slower pace and have to stop. I can’t recommend anyone do anything remotely dangerous, so don’t try this yourself. But if you do try it, keep scanning the roadside for places to bail if you detect a car. You may have to do it at an instant’s notice.
Commando night riding will make you aware of how many cars really go by you in an hour. A road that seems quiet in daylight may bring you a car every five or 10 minutes. That’s too many interruptions for commando-style riding. You’ll lose at least a minute every five, and that’s only if you can find a place to pull over when you need it.
Mountain bikers have ridden the trails at night for years. No worries about traffic there, though you may have to ride road segments to connect the whole loop. Night trail riders need powerful lights with good batteries to light the way over irregular ground. Prices range from around $60 for a basic rechargeable to more than $300 for the most powerful lighting. The little clamp-on lights that use ordinary batteries lose power too quickly. The same goes for headlamps. The rechargeable systems offer both handlebar and helmet mounting for the lights. Serious night riders will have both.
A light on the bike always points where the bike points. This is important.
A light on the helmet points where the rider looks. This is also important. The rider may be looking where to point the bike next, or may be looking for whatever’s making that crackling noise in the woods off to the side. It’s best to be able to light both choices.
If I can only have one light, I’ll have it on the bike. I’ve tried it with just a helmet mount, and it’s too easy to turn my head slightly away from where I need the light. The inexpensive combination uses the big, fancy light on the handlebars and an affordable headlamp on the helmet. You might not even have the headlamp on all the time. Save it for roadside or trailside repairs or desperately peering into the undergrowth looking for the Blair Witch.