Eddy current lights (no battery, no hub dymano)

[Iwan Barankay]

There is another category of lights that have a good use case for randonneurs: Eddy current contactless dynamo lights. These are somewhat magical lights that don't need batteries or a hub dynamo. Instead, they exploit Eddy currents (induction) when you hold magnets against alloy rims. So they only work with alloy, not carbon rims.

There are two companies that offer them. Magnic Lights (Germany) (https://www.magniclight.com/index.php/en/) and Reelight (Denmark) (https://reelight.com/en-us/collections/battery-free-lights). In fact, Magnic has a partnership with Reelight and supplies technology to them under license. I will focus on the Magnic lights as they have better tech, are built more robustly, and can accommodate all bikes and brake systems. (Note: I am not affiliated or sponsored by them)

For a rim break bike, it looks like this:

(picture source: FAZ.net) Yup, that’s it! It is contactless, so has much lower resistance or negligible resistance compared to a dynamo hub. They also come for caliper, cantilever, and disc brakes, along with this V-brake. 

This is what it looks like for a disc break (picture source: magnic light):

Use case

Let me cut straight to what I see as the use case for randonneurs: all-day safety lighting, and when low lighting is sufficient. I am exhausted by friends who get involved in crashes, and we should do everything we can to stay safe and be visible. These lights, once installed, are on all day. The system is less expensive than a hub-dynamo, has less drag, and is easy to switch between bikes. As they rely on contactless Eddy currents, they can’t supply as much light as a dynamo system, but the magnic lights did pass the German road traffic regulations (StVZO) approval, which requires them to emit a minimum of 10 lux at 10 meters. So it is impressive that they achieved that (the reelights didn’t). For most of our rides, this will be sufficient, but I would recommend taking a stronger USB light for descents and on rougher terrain. Well, we should all have at least two or three lights as backup on our rides anyway.

Note: the rear lights come with a stand light that works for up to 5 minutes, but not the front light. 

I have been in touch with the company's CEO, Dirk Strothman, who is very responsive and helpful. He has used this bike successfully on many long-distance rides.

I also see these lights as a great addition for those who ride multi-day events, where having back-up lights that work when all battery lights have run out is a great piece of mind. I wish I had them when I ran out of power in my three lights and my battery bank high up on a Swiss mountain pass a season ago.

Overall, I now view this product as mature and featuring high-quality components. The installation is easy for rim brakes and requires a bit more adjustment for disc brakes, but all within reason. They also offer all spare parts. I pushed Dirk about problems in terms of reliability and how robustly they are built, and he explained how they reinforced compounds and construction over time, and he shared this Instagram post of tumbling yet surviving lights: https://www.instagram.com/reel/DLPrfz-NJwf/?utm_source=ig_web_copy_link&igsh=NTc4MTIwNjQ2YQ

Ordering

Ordering to the US can be a bit expensive due to the more complex import situation, which adds high additional costs when ordering from a small business in Germany. If you are interested, please let me know, and we can place a group order. We can then coordinate directly with Dirk. A full set should cost around $220-$ 250, including shipping. 

Wrap up

I have ordered a pair and will report back if there is anything to report. Let me know your thoughts and questions. If you have experience with Eddy lights I would love to hear them as well!

More links

Webshop for rim and minimalist disc brake system: https://www.magniclight.com/index.php/en/webshop/magnic-microlights

Webshop for bigger forks or fender systems: https://www.magniclight.com/index.php/en/webshop/wega

Tech: https://www.magniclight.com/index.php/en/technology/eddy-current

Light distribution: https://www.magniclight.com/index.php/en/technology/light-distribution

Light comparison: https://www.magniclight.com/index.php/en/applicatons/light-comparison

[Bill Gobie]

Magnics offer significantly less resistance because they are significantly weaker. You get 11 lux from a pair of Magnics headlights vs 90 lux from a dynohub-driven Edelux II. The StVZO minimum requirement for intensity is not terribly impressive.

I got a 1st-generation light set as a Kickstarter backer many years ago. I doubt my experience with them is relevant to the current product, except that setup on caliper brakes was very fiddly. The mounting hardware looks improved but I don't see how you could make adjusting clearance to the rim significantly easier. Maybe I am wrong. 

The lights get brighter when the calipers move closer to the rim. On the rear wheel you get some brake light action. If you have to open the brake release because your wheel goes out of true you will lose a lot of brightness.

Bill

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[Iwan Barankay]

Hi Bill,

Thank you for sharing your user experience with the product when it was first released. It reinforces my assessment of the use-case, which I think is an important one, "for randonneurs: all-day safety lighting, and when low lighting is sufficient."

Iwan

[Dan Driscoll]

A bit of a tangent, but I’d like recommendations on a small battery operated flashing headlight for daytime use. I’m currently running my gen hub 24/7. 

DanD

On Dec 10, 2025, at 12:41, 'Iwan Barankay' via Randonneurs USA <randonn...@googlegroups.com> wrote:

Hi Bill,

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[C. Duque]

I have a 1st generation and also a 2nd generation Magnic Lights. Currently waiting for the newest version that attaches to the brake pads (Yes I use rim brakes) They also make an adapter for using the lights on bikes with disk brakes. The new lights are on the way and should arrive here within a week or two.

Here is my writeup of a few years back on the 1st generation lights: https://bike.duque.net/review-the-magnic-lights.htm

I use the 1st and 2nd generation on my bikes. Also used them on many brevets (have not done many brevets in a few years now). They are bright enough for my eyes but we all have different needs.

Carlos

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[Iwan Barankay]

Update. Dirk from Magnic Light offered us a 15% discount this month. Use coupon "RUSA15" in their webstore.

Carlos: Thank you for sharing the write-up. Very helpful! They now created a new design for disc brakes that does way with the cable so should be less prone to be damaged by debris. I will get that version.

Dan: Any small light that can take replaceable 18650 batteries would serve you well. Me personally I am tired of the hassle during an SR600 or 1200 to deal with batteries. 

[Fred Chagnon]

I used the Reelight NOVA (eddy current) rim dynamo lights early in my randonneur life. One of my sons is an active commuter, and I've since shifted the lights over to his bike. 

Front light: It's not suitable for night-time, but makes a decent "be seen" light. 

Rear light: Fantastic light. I quite miss it. It's very bright, and only blinks when the wheel is stopped. (I hate blinking lights in a peloton). 

I moved on to a bike with carbon rims, which don't generate eddy currents of course - hence why I repurposed them to my son's commuter bike. 

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