After reading the excellent “Bike Lights” article in Momentum’s Sept/Oct 2010 issue by Jonathon Reynolds which shares some research on when/where most bike accidents occur, I’d like to comment on the topic.
There’s a common misconception that you only need lights when it’s dark or getting dark. Due to almost getting hit in the middle of the day by a driver, whom I believe simply didn’t see me in the dark shadows of a tree (some people’s eyes don’t adjust very quickly to extreme lighting changes), I have since strongly encouraged people to use flashing lights, front and rear, whenever they ride and not just when it’s getting dark.
There’s a good reason why many newer motor vehicles have lights that come on automatically whenever the engine is running; they’re called “Daytime Running Lights”. While US car manufacturers have effectively lobbied against requiring them Canada and many European countries have enacted legislation requiring them on motor vehicles while at least one, Germany, requires front and rear lights be working at all times on bicycles.
If you need data to be convinced, take a look at this data on when the bulk of crashes occurred – DAYLIGHT HOURS! Yes, the bulk of the fatal crashes have occurred later in the evening hours but it’s obvious your visibility isn’t just important when it’s dark out (courtesy of the Michigan Traffic Crash Facts tool).
Additionally, people should definitely stick with lights that have easily rechargeable batteries or USB rechargeable so that they’re more likely to use the lights all the time rather than trying to conserve batteries. We stock many affordable lights at MSU Bikes and can special order just about any other light on the market.
Check out a 2017 WSJ article on the topic:
“How Cyclists Can Stay Safe on the Road – Bright colors, bright lights and positioning on the road can help cyclists be more visible to drivers”
Finally, I see way too many cyclists riding around with lights that are hardly visible, or hanging off a backpack often pointing to the ground, apparently thinking “I’ve got a light, I’m safe”, but apparently have no idea how invisible they are. I’m not sure if it’s the nature of rechargeable batteries or the modern LED lights, but it’s also best to have backup lights on the rear and front as I’ve had them look bright at the start of my commute home only to discover they died sometime during my ride.
So, be sure to check your lights often and recharge or replace those batteries to stay alive! And make sure they’re aimed properly down the road so they’re actually visible to motorists.