Lupine’s SL Mono is the brand’s first headlight with an integrated battery with StVZO approval. This gives you the best of both worlds, a crisp beam cutoff with a simple all-in-one setup for quick installation or removal. The SL Mono’s premium retail price of $250 is matched with an all aluminum construction and serviceable design that ensures you can use the light for years to come. Lupine offers replaceable batteries and a variety of spare parts for the SL Mono to allow you to repair or service the light on your own, a rare feature in the bike light market. To make the SL Mono smart, the headlight also includes an integrated ambient light sensor to automatically switch between day mode and low mode based on the environment. As with other Lupine products, the headlight has three simple output modes with a maximum output of 700 lumen and 16 hours of runtime.
The Lupine SL Mono combines an intricately engineered projector lens with an integrated battery for a compact and bright StVZO rated headlight.
| Rating | 9.2/10 |
| Retail Price | $250 |
| Measured Weight (in g) | 150 (headlight), 19 (mount) |
| Likes | + Sharp beam cutoff and crisp pattern rom projector lens + Fully serviceable design including an affordable replaceable battery + Clever side mount with available GoPro adapter |
| Dislikes | – Premium price – Lacks separate DRL lighting element for daytime riding |
| Where to Buy (US) | Lupine |
UNBOXING
The Lupine SL Mono comes in a compact square cardboard box with branding printed directly on it. Inside the box you’ll find:
- SL Mono headlight
- Metal handlebar mount
- Side bolt + two washers w/ Allen key
- USB-C to USB-A charging cable
- Screw driver (for opening headlight housing)
- Instruction manual
- Lupine stickers
Lupine has done a great job eliminating extraneous plastic packaging and using simple cardboard dividers to keep the headlight securely in place.
MOUNTING
The Lupine SL Mono uses a clever side mount which ensures the headlight can be centered directly in front of the bike stem. Included with the light is a metal cam-style handlebar mount which has an extended bracket which is bolted onto the side of the SL Mono. The all-metal design not only looks premium but it’s a far cry from the traditional rubber straps found on cheaper headlights. You can also easily adjust the angle of the light by keeping the bolt slightly looser and rotating the headlight to find the optimal angle. It’s a well designed mount that keeps the light steady even if you ride on rough roads or gravel paths. Lupine also offers accessories like a GoPro adapter which bolts onto the side of the headlight and allows the SL Mono to be attached to the bottom of an out-front-mounts like the Topeak UTF for an even sleeker installation.
FIT & FINISH
The Lupine SL Mono takes Lupine`s popular SL series of headlights and adds an integrated battery for a compact form factor. Specifically, Lupine has borrowed the SL Nano’s lens design and extended the housing to accommodate an internal 3300mAh battery. As with all Lupine products the SL Mono uses a full aluminum housing with a fully serviceable design. That means despite the impressive IP68 rating, you can actually open this headlight and replace the battery. There are recessed screws on the backside of the housing that can be opened using the included screwdriver for servicing the light. Due to the integrated battery, the SL Mono has more of a rectangular profile instead of the round design the Lupine SL AF and other SL variations have. It’s still an attractive design that blends in well and almost has a retro look that reminds us of dynamo lights.
One of our favorite features of the light is the projector lens with an outer ring that features horizontal diffusers. Not only does this have an attractive design reminiscent of a cat’s eye, but it also creates a sharp and crisp beam cutoff with a clean beam shape. With this smaller form factor there is no dedicated DRL lighting element, something the Lupine SL AF has. Instead the outer ring’s horizontal diffusers help create a uniform illumination to improve the visibility of the light and widen the beam. Heat fins are cut directly into the housing to dissipate heat and add more surface area to the housing. There is a single power button on the top and a side bolt that is used to mount the headlight.
Lupine has kept the user interface on the headlight simple and easy with only three output modes: eco, low and high beam. Due to StVZO regulations, there are no flash modes available on the headlight. A single press of the button cycles through the available modes. As with Lupine’s other lights, like the Lupine Rotlicht, configuration mode can be accessed by doing a long hold (6 seconds here) and counting the number of flashes. There are only four configuration options: light sensor enabled (default is off), double press or single press to power on light (default is double press), battery warning early or late (default is late) and finally resetting to factory settings. While it isn’t intuitive to use without reading the manual, the built-in configuration means you don’t need a separate app or have to worry about said app from becoming unusable with operating system updates.
What makes the Lupine SL Mono a smart headlight is the integrated ambient light sensor. Lupine leaves the mode off from the factory but you can re-enable it via the configuration options. With the sensor on, the light automatically switches between eco mode and low mode depending on the ambient light conditions. It’s easy to know the mode is on as you cannot access the eco mode manually when the light sensor is on. The feature is convenient as it allows you to conserve battery by having the light automatically dim to eco mode when there is enough light around you. The backlight on the power button also makes it easy to visually see which mode you are in.
LIGHT OUTPUT
The Lupine SL Mono only has three constant modes to choose from. Eco mode is rated for 1.5W / 150 lumen with a long runtime of 16 hours. Medium mode provides 4W / 350 lumen and a 4.5 hour runtime. At full output, the high mode provides 8W / 700 lumen and a respectable 2 hour runtime. We found the runtimes to be accurate and the jumps between modes to be large enough to easily differentiate while riding. The project lens creates a beautiful trapezoidal beam that illuminates everything from your front wheel to multiple car lengths ahead of you. Not only is there a sharp beam cutoff that keeps the glare out of oncoming traffic’s eye, but the beam is quite wide at about a car lane width in front of the light and two car lanes wide at the furthest point.
It’s a very impressive beam that almost looks like it has been photoshopped as the edges are sharp without any artifacts typically found on reflector style headlights like the Trek Commuter Pro RT or Topeak WhiteLite 800BT. There is more than enough light for commuting or faster paced road cycling. Low mode works well for slower paced riding while eco is best reserved for daytime riding. High beam mode looks brighter than standard headlights with 700 lumens as all the output is focused on the ground. The only negatives with the light output is the fact that there are no side cutouts to improve the side visibility of the light.
THE VERDICT
Overall, we found the Lupine SL Mono to be a well designed headlight with a compact all-in-one design. With the battery integrated into the housing you don’t have to worry about bulky battery packs or routing wires through your frame. Instead, the SL Mono has a bright 700 lumen output and crisp beam cutoff that can quickly be installed or removed from the bike. We were particularly impressed with the sharp beam cutoff which offers a wide trapezoidal beam free of any artifacts. The main downsides of the SL Mono is the premium price – something that is justified by the replaceable battery and aluminum design – and lack of separate DRL lighting elements. That said, if you’re looking for a bright headlight with a sharp beam cutoff that can outlast your bike then the Lupine SL Mono is worth considering.
Disclaimer: The product for this review was provided by Lupine. The views expressed on this website are solely those of the authors and are here to help people make an informed choice before a purchase. The authors or the blog itself does not get any monetary compensation from the product manufacturer or third-party websites/vendor links that are posted here.