Review: Knog Blinder 640 light

//Review: Knog Blinder 640 light

Review: Knog Blinder 640 light

Know Blinder 640

We live in a time of incredible illumination. No, we’re not talking about genetic medicine or disruptive algorithms or amazing philosophical discourse around the globe.

All that’s nice but we’re talking actual illumination. There has never been a better time to light up your way on a bike. Fenix, Light in Motion, Blackburn, Cycliq, Nightrider, Cateye and others have all dialed up the lumens.

One company that consistently piles on the goodness is the Aussi outfit Knog. They’re smart, they’re funny, have Chinese take-out food product boxes and awesome and stylish lights.

640 lumens

640 lumens

We’ve used their Blinder Road 2 for several years. It’s compact, good-looking, simple to attach and recharge and gives us all the light we need for early morning and evening bike commutes and some trail riding at night.

We loved the Knog Road 2 and apparently thieves loved it too because ours was stolen several months ago (along with our trusty Serotta road bike.) Happily we’d just come into possession of the more powerful Knog Blinder 640 ($119 USD). Sometimes karma evens out life’s ups and downs.



First, the specs. 640 lumens, USB charging, 100% waterproof, 16 (vertical) and 24 (horizontal) degree elliptical beam and four light modes – the usual high, medium and low plus flash. But we’re getting ahead of ourselves.

Out of the box, the Blinder has a nice form factor and design sensibility. Now that’s a matter of personal taste but the 640 has an industrial speed-gun look with a grey aluminum barrel (nice for the heat dissipation) and black, rubber-like back end that has a grippy, tactile feel. Nice for handling when putting on and taking off the bars in wet weather. Overall, the unit feels solid and substantial and has an almost Apple-esque design aesthetic.

Construction and materials seems to be a consistent highpoint for Knog – at least based on our three Knog lights – the Road 2 and a rear Road R70. These feel like high quality tools, not stamped out, lightweight accessories that don’t plan on being around for years of service.



Once out of the box, the Blinder 640 comes with two sizes of interchangeable rubber straps for mounting to the bars, 25-30mm and 30-35mm. These are super easy to switch and a little cam lever flips over to tighten down. This is genuine quick release action and I like that the mount is integrated into the base of the light – you’re not going to lose it.

This is the same mount as our Knog Road 2 so we can say twice over that there’s nothing loose, no shake to the light once it’s on the bar. Now we’ve read that some people find the mounting to be a little loose and need the included foam strip but we’ve had the 640 on road and mountain bars without any issue at all. The caveat is that no, we didn’t try it descending rocky single-track at terminal velocity.



As far as run-time for the 4 light modes, Knog lists 1.7 hrs for high, 3.3 hrs for medium, 7.3 hrs for low and a full 15 hrs for flash. On our rides, we generally found that to be close, a little under. Our commutes and rides are generally under 2 hours so we go full beam all the way. Because switching between the modes is easy, stretching your run time isn’t a difficult task. There’s a status light that lets you know mode and battery charge status.

Recharging is another area where the Knog Blinder 640 shines. As you can see from the photos, one side of the charging plug is integrated into the unit and folds out from the back. Then you simply use the included USB cord to charge off your computer. We do agree with other reviews that found the little flip out plug to be “fiddly.” We had no trouble but it’s the one place where a beefier plastic door seems in order. When we commute into work, we can quickly take the Knog off the bars and plug into the computer in less than 30 seconds.

The button to set the light mode and power on and off is well-done. This was an issue with my Knog Road 2 — loved the light but the button for changing modes was difficult to press and activate and a real challenge when wearing gloves. The 640 however is simple to turn on and change modes easily and the touch and feel are responsive.

Now, the real meat of the matter: those 640 lumens. It’s the most powerful light that Knog makes and for us as a commuter light, it really does the job. When we’re on the trail, we use a second light on the helmet to give us the side-to-side vision and the combo is plenty bright for us. Like battery life, some people are never satisfied with lumens but 640 fits the bill. If we where doing serious downhill at higher speeds, then we’d have to re-evaluate.

Overall, we’re super happy with the Knog 640 Blinder


Well-built, designed and constructed

Simple, stable, quick-release mount

Good price per lumen ($119 USD)

Handy integrated USB plug

Works best as commuter and road light

Recommend two light system for aggressive trail riding


Integrated USB plug could be beefier


Blinder 640

Know Blinder 640

Know Blinder 640

2019-02-03T15:45:17-07:00May 11th, 2016|Product Reviews|


  1. Der Flahute May 11, 2016 at 9:36 pm - Reply

    Rubber straps are nice until they break fairly soon & unit is useless… Poor design.

    • walshworld May 13, 2016 at 11:00 am - Reply

      Thanks for dropping in Der Flahute, I haven’t had any issues and they are easy to replace. I guess it’s a decision about where you like the integrated strap or a separate piece. Matt

  2. Mehmet June 19, 2016 at 5:31 pm - Reply

    Personally, i’ve never had an issue with the straps. Also, looks like the straps are replaceable with these lights too!

    • walshworld July 11, 2016 at 12:05 pm - Reply

      Thanks for checking in with some intel. Matt

  3. […] It’s nine LED lights packed in a small, compact unit with a minimalist design that anyone with a clean design aesthetic will appreciate. If Apple was making a small bike light, this is what Palo Alto would produce. People who like an unobtrusive light that melds to their bike will love the Mini’s low-profile attitude. (We’ve also reviewed their well-designed Blinder 640 front light.) […]

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