I wanted to learn more about bicycle safety lights. I’ve used high power lights for 24 hour racing and night riding, but that’s a different category altogether! Before I did this research, safety lights consisted of “put a blinky rear light on the seatpost and go ride.” I actually enjoyed learning more about lights and I’m excited to share what I’ve learned!
So where do we start? The main elements when I looked through a bunch of other videos and articles about lights were lumens, brightness for day vs night use, lights to be seen vs. illuminating your way, battery life and type of battery, and beam width (how far the light reaches), and flash modes.
As a quick conversion, you’ll sometimes see brightness in terms of candlepower. 1 candlepower = 12.57 lumens. Another quick note is that different countries have specific legal requirements for lights. A quick google search and it actually wasn’t easy to find what those were. With terminology, “lux” is another word that can be confusing. To greatly simplify it, lux is used in an equation that calculates lumens. Here’s a quick online calculator. Watch this if you want to geek out on it.
To simplify things, the best light to buy is the one that you’ll use. For me, that also means ease of mounting and good battery life. It’s also recommended to have both a front and a rear light. The rear light is for obvious reasons- so you can be seen from behind. The front light will also make you visible in intersections where oncoming traffic will need to see you.
Most people think about using bike lights for commuting in the dark, but more and more people are using lights during the day for safety. And for good reason, according to this report, cyclist deaths due to motorists increased to 6.3 percent in 2018. Technology in new vehicles is improving to help distracted drivers, but taking your own safety measures is a good idea. Anytime I road ride, I use lights but to be honest, I hardly road ride anymore simply because I fear for my life! A light you could use for a daytime running light would be the Topeak Aero USB 1W Combo,
A rear blinking light is the minimum for safety during the day. If you’re riding in low light or dark, you’ll want a higher power rear and front light. A 2012 study in Denmark showed a 19 percent decrease in bike related accidents with daytime running lights. You want a minimum of about 100 lumens for daytime running lights.
In terms of how bright of a light you need for different conditions, I found this great image from Cycling UK that was in line with everything else I read from different sources.
Rural lumen recommendations is also the same for illumination and seeing where you want to go. For trails as you can see above, mega brightness is good! The faster the speed, the more lumens you want. For illumination (also for commuting for finishing my ride at night, say riding home from the trail), I have the HeadLux 450 USB and RedLite Aero USB 1W.
For rear lights, you want around 60-70 lumens and it is recommended that you have one steady light and one flashing light. Many people like a row of LEDs like the Topeak Aero USB 1W Combo or RedLite Aero USB 1W because they also provide side visibility.
A note about beam width- how wide the light shines. If you’re riding in the rain a lot, remember that light travels slower through water than in the air so you’ll lose about 33% of your beam angle. It will become more narrow. If you’re a wet weather commuter, consider getting a wide beam angle light to help account for this loss.
Each brand has it’s own way of creating their special beam patterns. Topeak has a special “Beam Pattern” call “Dural-Zone Visibility” on the WhiteLite HP 500. The beam allows clear near and far visibility focusing the main beam downward to prevent affecting pedestrians or oncoming traffic. Blinding oncoming cars is definitely a concern and something to think about when selecting a beam pattern.
I prefer lights that are rechargeable via USB and are easy to mount. Those are two things to consider when looking at lights to buy! In terms of charging, it’s a good idea to pick a light that will warn you when it’s almost out of battery. The Topeak front and rear lights I use are all designed with a little LED indicator on the light body or inside the lens. If the LED indicator lights up red, then the battery power is less than 5%. Some other brands also include a similar feature, but not all lights have it.
Let’s talk about flash patterns for a minute
When talking about flash patterns, pick a light that has a few modes to choose from. My Topeak front lights have 4 modes: high, middle, low, and blinking. Trail lights for 24 hour racing also have different modes. Each mode has a different rated lumen output meaning high will use the battery faster than low. For tail lights, I also like the Redlight Mega for all the different flash modes. Blinking lights will help you stand out more than a steady light.
One last safety piece you can add to your bike are accessories with built-in lights. I’ve seen lights you can put in the spokes of your wheels. Topeak has an iGlow series that includes fenders, seat bags, and even your pump. However, these are not a substitute for safety lights, but merely an add-on.
For fun, I’ve also included a video for UV, waterproofing, and light intensity testing, courtesy of Topeak Quality Control Team. Some lights have built-in accelerometers that change their blinking patterns as a car approaches. I’ve seen other lights with a built-in video camera to catch crashes. You can get pretty techy if you choose!
Happy riding and stay safe!