Reelight SL120 Bike Lights – Lights that are ALWAYS ON
I have lights on the front and back of my helmet, as well as on the front and back on my bike. I use rechargeable batteries, and I’m pretty good about switching them regularly.
Still, I’m not perfect, and I wanted to make sure I was never caught coming home from work without lights. That’s why I bought a complete set of Reelight SL120 bike lights.
The Reelight SL120 bike lights are powered by electrodynamic induction, which means that power is generated as your bike moves, by a pair of spoke-mounted magnets passing over a copper coil (inside the light unit). Once you have them mounted, they are always on. You don’t have to remember to keep the batteries charged, or even to switch the lights on. As long as you’re moving, your Reelight SL120 bike lights are on.
Even better, thanks to a built-in capacitor that stores energy, Reelight SL120 bike lights stay on for a couple of minutes after you stop pedaling. So even when you’re stopped at traffic lights, they’re still going. Note that the other lights in the Reelight Lights series do not have this added bonus. Also, note that the lights will not work at full capacity when you first get them, as it takes a while to get the capacitor charged up. After this first time use, however, they are up to speed within a couple of minutes of starting your bike journey.
Related Post: 7 of the Best Bike Lights for Street and Trail Cycling
Legal Issues and Reelight SL120 Bike Lights
These lights were invented in Denmark, where there is a legal requirement to have lights on the back and front of your bike. They meet the legal requirements of most countries, and even offer a left side driving option. A few countries (such as Holland and Sweden) have laws against flashing lights, so Reelight offers models with a steady light (the SL150 series). Some claim that because these lights attach to the bike’s axles, they are too low to meet the legal requirements of some countries. I am not sure about that, but for me it is a moot point, because I would not use these lights as stand-alones, only as extra or back-up lights. My primary taillight is my intensely bright Serfas taillight (reviewed here) and my primary head light is my wonderfully bright Lumintrail headlight (reviewed here).
Fitting your Reelight SL120 Bike Lights
The compact Reelights SL120 Bike Lights will fit most bikes. For my bike I use Reelight SL120 extended, which have longer, stainless steel brackets to allow room for my disc brakes. Reelight recommends that there should be no more than 3 mm between the magnet and the light. Mine were poorly fitted by my bike shop, with the front set touching and the rear set more than 3 mm apart. Will I never learn to check work at the bike shop before I take my bike home? I had to adjust them to get them working perfectly, but it really was not brain surgery.
What I Like about my Reelight SL120 Bike Lights
First off, I don’t have to worry about batteries. Which also of course makes them really green friendly – always a great thing. However, for me the greatest benefit of the Reelight SL120 lights is simply that my lights are always on, even when it suddenly gets darker, or the batteries on my other bike lights run down. This could potentially save my life – I know a woman who was hit head-on by a car while she was cycling after dark, because she did not realize that her front light battery was completely dead. (Luckily, she survived.) Plus, my Reelights are on during the day as well. I once spoke with a bus driver who told me he prefers cyclist to have lights on even in the daytime, as he can see them from two blocks away (but finds it hard to see them at all without lights). Bearing this out is a study conducted by Reelight and other researchers with 4,000 cyclists over one year, which showed daytime lights on bikes reduced accidents by 19%, and reduced injuries to cyclists by a staggering 47%. (Thanks to Canadian safety activist and academic Neil Aronson for drawing my attention to this study.)
Minor Drawbacks of the Reelight SL120 Bike Lights
These lights are not stand-alones – you still need your regular bike lights for biking at night, especially on the front, as they do not light up the road ahead of you. Reelight SL120 bike lights are more about being seen than seeing. So I definitely see my Reelight SL120 bike lights as back-up lights. They make sure I will never be caught lightless, but I would not want to have them as my only lights.
Some people might have a problem with the weight of these lights, as they are pretty solid. I laugh at such notions, seeing that I can lose or gain 4 pounds in a single day without even thinking about it. (Actually, I am much better at GAINING 4 pounds in a day without even thinking about it. My Super Power is gaining weight. No, not what I asked for …)
For me, on my sturdy commuter, a few ounces more or less is not even worth thinking about.
Bottom Line on Reelight SL120 Bike Lights
Reelight SL120 are always there and always on, with no running costs. So even if they save my life only once, it’ll be money very well spent. My opinion is that it’s well worth while to shell out a few of your hard-earned dollars on these clever and possibly life-saving bike lights. You can have the whole set shipped from Amazon for about $50. (Sale price – might not still be applicable.)
To read much more about bike lights, see Average Joe Cyclist Guide to Bike Lights. If you want a light that will enable you to see your way in pitch darkness, see my review on the super bright Lumintrail headlight.
Below are links to all of our best posts on bike lights!
How to use this slideshow: Clicking on a picture will take you to that post. Hovering your mouse over a pic will pause the slideshow. On the right and left, there are arrows to move ahead or back.
Check Out Our Most Popular Posts!
Did you enjoy this post or find it helpful? If so, please support our blog!
We write this blog because we love cycling. But we also need to earn a living, so we REALLY would appreciate if you click through to one of our reputable affiliates for your online shopping. We are proudly affiliated with Amazon, which sells pretty much everything, and has outstanding shipping and return policies. When you buy from our affiliates we make a small commission, and this is the only way we earn any income. Plus, it costs you nothing at all - a real win/win situation!