Knog Blinder 900 Bike Light Reduces Tunnel Vision on the Trail

The Knog Blinder 900 offers the same size and weight advantages of many all-in-one bike headlights but with better than average battery life and a wider beam pattern for extra peripheral vision on the trail.

Mountain biking at night is a lot like riding with blinders on, though the Knog Blinder does its best to illuminate the sides of the trail too. This new compact bike light delivers impressive battery life and is easy to mount to a handlebar or helmet.

Knog Blinder 900 specs

Manufacturers tell us lumens aren’t everything when it comes to choosing a bike light, and yet once again it’s right there in the product name: the Knog Blinder 900 boasts up to — you guessed it — 900 lumens of brightness. The light features four LEDs arranged in a square pattern with optics designed to produce a narrow beam from the top two bulbs and a wider beam from the bottom two. Small windows on the left and right of the lamp provide a bit of added nighttime visibility from both sides.

While most of us have a vague understanding of the relationship between brightness and lumens, battery metrics aren’t quite as easy to grasp. Knog says the Blinder 900 comes with a “21700 3.7V lithium ion battery” which is… good? Perhaps a better way to put the quality of the battery in perspective is to mention that the Knog Blinder 900 lasts up to two hours on high (other all-in-one lights with similar brightness we’ve tested tend to offer about an hour and a half) and is just the size of a Snickers bar (the original, not the King Size).

On the tech side, the Knog Blinder features a color-changing charge indicator you can tap to see how much juice is left during the ride. The light has a USB-C port for recharging, and doing so takes about five hours from empty. There are three brightness modes (900, 450, and 200 lumen) and three flashing modes, one of which is more of a pulse.

Knog includes two mounts in the box, one with a silicon handlebar strap that fits bar diameters from 22.2mm to 35mm, and another that’s compatible with GoPro mounts. The latter is actually optimized for mounting to the underside of K-Edge style GPS handlebar mounts, though I found it works just fine with GoPro helmet mounts too.

The light snaps into the mounts, which can be angled up or down, though there is no way to rotate the light side to side once it’s in the mount. Knog notes the Blinder is CNC machined from aluminum, allowing the body to double as an effective heat sink. My test sample weighs 169.3g.

The Knog Blender lights take the place of the round PWR series lights we reviewed last year.

Into the night

The Knog Blinder 900 is similar to a lot of all-in-one bike lights in terms of its weight and form factor. It’s small and lightweight enough to use as a helmet light, or you can mount it to your handlebars if you prefer. Since Knog includes two mounts in the box, one option is to place the GoPro mount on your mountain bike helmet and the other on your gravel bike bars, and use one light for both.

With the GoPro mount the Knog Blinder 900 sits a little high on my helmet; the first few test rides involved several snags on low-hanging branches. The grippy on/off button is easy to find by feel, even wearing gloves in the dark.

Knog markets the Blinder 900 optics as being optimized for road riding, which in practice means a slightly wider beam pattern than a typical mountain bike light. The extra width is definitely noticeable on the trail. On the one hand, it seems like a waste of brightness. On the other hand, narrower, focused beams can definitely lead to tunnel vision and tight shoulders, even when you’re running a helmet light.

At full power I found the Knog Blinder 900 bright enough for me to ride 10-12mph on wooded singletrack when paired with a second light. Most riders could get away with running the Knog Blinder 900 by itself but I recommend having one light on the bars, and another on a helmet. For most of my test rides I paired the Knog Blinder with a Moon Rigel bike light.

Because the mount doesn’t allow the light to rotate it needs to be placed on a part of the handlebar that’s perpendicular to the fork, typically close to the stem. Snapping the light into the mount is well, a snap, and both mounts held securely throughout my testing.

The Knog Blinder 900 stands out from other all-in-one lights I’ve tested for its battery life. On a typical two hour night ride I toggle between brightness settings depending on my speed, and rarely use more than half the juice.

Pros and cons of the Knog Blinder 900 bike light


  • Lightweight and multiple mounting options included in the box
  • Good battery life
  • Easy to use


  • No ability to rotate the light in the mount
  • Beam pattern is not trail optimized

Bottom line

The Knog Blinder 900 offers the same size and weight advantages of many all-in-one bike headlights but with better than average battery life and a wider beam pattern for extra peripheral vision on the trail.

  • Price: $79.95
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