Bicycle lights have been something of a hot topic as of Spring 2011, from Ethan Frier and Jonathan Ota's "Project Aura" to, say, LED by Lite's ill-fated Kickstarter campaign. And while cycle-obsessed designers continue to explore new and innovative ways to illuminate their conveyance of choice, removable head- and taillights remain the accessories of choice for most urban riders.

Melbourne-based Knog is among the biggest names in the bike-light space: their line of one-piece silicone lights has quickly expanded both in terms of shape and size as they've built a loyal following on pace with the growth of the cycling trend over the past half-decade or so.

Yet Knog has transcended their outward hipster appeal with their unmatched approach to product design, making them the go-to purveyors of bike illumination for the fixed-gear set and hardcore commuters alike... not to mention modern makers.

Incidentally, my Frog Strobe went out of commission due to a faulty contact halfway through the summer and I was just about to pull the trigger on a new one when who else but Jonathan Chan of Knog's design team reached out to me about their new(ish) USB-rechargeable lights. He was kind enough to send me a care package with a pair of new lights, as well as a few other goodies, for what I hope is a comprehensive review for the design-minded urban cyclist.

USB-Rechargeable Boomer Bicycle Lights by Knog

Pros - They're super bright - Unique, thoughtfully-designed look and feel - USB recharging is as convenient as it gets

Cons - Not entirely weatherproof - Indicator & electronics - Durability issues (possibly due to rare defect)

Design

Above all else, Knog is known for their distinctive design, specifically the silicone exteriors—available in a range of colors—which are more or less iconic within the bike light category. While there's no denying that good looks have taken the Australian company a long way, I sympathize with their mission to make safety "cool," for lack of a better term (see also: Project Aura). I'd go so far as to say that Knog is the Oxo of bike lights, not least for their funky overmolded aesthetic, and I think the design team has done a great job with the lights on a visual and tactile level. (The Boomers, in particular, look like oversized erasers.)

Unlike their smaller lights, for which only the lid to the battery compartment is removable, the silicone casing of the Boomer is entirely separate from the plastic LED+battery component. Getting them apart isn't quite intuitive, but (as with many bicycle maintenance tasks) it gets easy once you get the hang of it. The removable plastic cap that protects the USB plug itself is the same between both the front and rear models, but the light itself and its protective skin are not: both lights are perpendicular to their points of attachment, but the bulk of the headlight is designed to attach perpendicularly to handlebars while the body of the taillight is aligned with the tube to which it is attached, i.e. one's seatpost.

I was interested to find that each enclosure secures the light differently, both within and without: the difference is largely attributable to the different attachment mechanisms, where the hook for the rear light is part of the plastic part as opposed to integrated into the casing. The headlight is secured with a large silicone loop and hook, fused to the silicone. The taillight, on the other hand, has a single skinny strap with a loop at the end, which feels somewhat less substantial (and proved to be so; see Materials, below).

Of course, insofar as the Boomer is one of Knog's higher-end offerings, the "super-powered LED" is bigger—and appreciably bulkier—than its smaller, less powerful siblings. It's not "aero," as they say, but all things considered, the form factor of the Boomer is relatively unobtrusive and far more elegant than a lot of the plastic clip-on lights—which often require extra mounting hardware—that I've come across. Besides the USB-charging feature, the fact that Knogs come in a single piece may be their biggest selling point.

Still, the Boomer is just a little too big to fit comfortably in the average pocket, which means that they often end up at the bottoms of backpacks when not in use. If I'm traveling sans bag as I sometimes am at night, I usually clip the lights to my carabiner for safekeeping, though on a few occasions, the light has turned on of its own accord, putting me in the semi-embarrassing situation of having an instant disco attached to my hip(ster cred). Acquaintances and/or waitstaff have been kind enough to inform me of when this happens, which is not often, though friends have reported that their Knog lights are likewise known to activate of their own accord in pockets, backpacks, etc.

Conversely, I've left the lights on my bike while it was locked up at various locations throughout lower Manhattan and Brooklyn for hours on end without incident. For what it's worth, there's no outward indication that the lights are the USB-rechargeable Boomers as opposed to battery-powered ones, though this probably discourages pilfering about as much as tiger-repellent repels tigers. In fact, I imagine that the regular ones use the very same silicone enclosures, discussed below, and LEDs.

Materials

The silicone is soft to the touch, but just sticky enough that it picks up dirt in less-than-optimal riding conditions, which is generally the case in New York City. Easy come, easy go: dirt comes off with no more than a dab of a damp paper towel, and in the case of the black Boomer, it doesn't really show at all.

Knog claims that the exterior is waterproof, but in my experience, the Boomers were highly water-resistant—but not completely impervious—to the elements: during a particularly torrential ride, the rear light was subject to a bit of leakage, as I found dirt and water within the silicone when I got home. I wiped down the plastic casing of the LED+battery piece and I haven't noticed any adverse effects, so I assume that the internal workings of the light have remained undamaged.

As for the material itself, the enclosure is supple and sufficiently stretchy, but this ends up being a double-edged sword: the attachment mechanism means requires a certain amount of force and relative precision to secure the silicone loop to the plastic hook, which makes it virtually impossible to secure either the front or rear light with only one hand. Again, it's not rocket science: put the lights on before you get in the saddle.

Meanwhile, at some point in the past month or so, I'd managed to rip the loop of silicone that fits on the plastic hook of the body of the taillight, a structural but not yet critical tear that threatens to give ’way any day now. I have no idea whether this is solely attributable to the often-hasty attachment, detachment and general mistreatment that I've subjected it to, but suffice it to say that I expected it to last longer than three months.

I'd noticed that the tear gradually got worse, but, in the interest of preserving Knog's good name, I 'anonymously' contacted Knog customer support—i.e., via a friend—for a replacement case and they were happy to oblige, noting that this was an unusual issue. I asked Jonathan about it and he offered his take:From what I understand, this can happen from time to time either due to hidden air bubbles in the silicone and/or the silicone getting nicked by a sharp edge, plastic flash etc... we do get requests for replacement straps from time to time, but not a whole lot in the overall scheme of things.

Features

Rare defect aside, the LEDs themselves are as bright as any bicycle lights I've seen, imparting a beacon-like brightness to the Boomers and their rider. Friends have told me that they're visible from as far as the eye can see, at least on city streets—in fact, when they're freshly charged, I can't help but feel like the cynosure of drivers in my immediate vicinity (i.e. when I speed past them in traffic). Unfortunately, the prevalence of streetlights has made it more difficult for me determine how well the headlight illuminates the road, but the manual notes that the Boomer is a "Safety light only."

It's hard to pinpoint the exact battery life, but Knog lists the "burn time" of the front Boomer as 3.5hrs (constant) and 12 hours for strobe mode. The rear, however, is listed at 60 hours in fast flash—I can't tell by eye, but I can't imagine that the "fast flash" is five times as frequent as the strobe mode. Thus, I'm not sure if this discrepancy has to do with the color of the light or the mode itself; either way, I find that it's in my best interest to charge them at least once a week.

Regular charging habits also serve to preclude the possibility of missing the meek battery indicator. When a Boomer is running low on juice, it will let you know with an occasional off-color flash (when they're in any of the blinking modes), as well as when you turn it off, but I can't say it's foolproof. There have been at least a couple nights where I've arrived at home to find that my rear light burned out at some indeterminate point during my ride, so I've taken to charging them at the slightest sign of diminished power, typically once a week or so.

Similarly, I'm not sure exactly how long it takes to charge; I usually leave them overnight, which is more than enough time. It's possible to get a bit of juice in them for a fast charge without topping up the power supply, though this probably isn't the best practice for rechargeable batteries.

It's worth mentioning that the lights are roughly 1.5–2 times bigger than a standard USB port, so it's not possible to have both of them side by side in, say, a MacBook Pro (nor do they fit in Apple keyboard USB ports). Alternately, the lights seem to be sufficiently low voltage that they can be charged with any wall socket USB charger.

On the Road

Powering on and off is a snap; the button (on the plastic piece) is nicely integrated into the light and it's responsive enough to tell if you're actually toggling it. I didn't find any practical application for having three different flashing modes—Strobe Flash, Fast Flash and Random Flash—and, in fact, it can be a little annoying to have to toggle through the other modes to get to the solid mode. Turning it off (a full five-click cycle) is a little easier because it can be done by holding the button for an extra second or two in any mode.

Still, Knog has a somewhat spotty history of shaky electronics based on secondhand accounts—Jonathan mentioned that they've improved a lot over the past year—and I've found that the Boomers can act a little haywire on occasion. The headlight has a tendency to skip to constant mode if I hold the button for more than a second (which is actually a plus for me, as I mentioned above), while the rear sometimes takes an extra few taps to turn off.

Nevertheless, in the rare instance that I've had to turn on the rear light on-the-go, I've been able to reach down to my seatpost and power it on while maintaining control of the bike. Here, the brightness is crucial: even though the it's pointing behind me, I can tell whether it's on simply by looking down at it.

Regarding the headlight, I'm aware that particularly bright headlights can be blinding when seen head-on, such that my visibility comes at the expense of a drivers' ability to see anything else. I make a conscious effort to prevent this phenomenon by directing the lightslightly downward, towards a point about two meters ahead of my bike, which limits the illumination (of the road) but hopefully makes a difference to anyone else on the road.

A sidenote (and confession): New York City is, for the most part, very well-lit at night; as such, I'd never used a front light, for visibility or otherwise, prior to receiving the Boomer. However, now that I've been reviewing the Knogs, I can honestly say that I now find the front light indispensable, and I've increasingly picked up on situations where it very well may have kept me out of harm's way. Fellow cyclists, I implore you to get both rear and front lights,—in red and white, respectively—for everyone's sake.

The Almost-Fatal Flaw?

Long story short: the strap eventually reached the point that it looked like it might snap the whenever I attached it to my seatpost—a standard 27.2 mm Ø—and for a while, I was worried it would snap and liberate itself while I'm riding (in the blind spot of an 18-wheeler on a pitch black stretch of pothole-ridden road, no doubt). I eventually resorted to attaching it to the skinnier seatstay of my bike in vain hopes of preserving the ever-weakening strands of the strap while I eagerly awaited the new enclosure.

The tear worsened over the three-week span between when I first noticed it to when the new enclosure showed up. You'll also notice a small nick in the body of the silicone, at bottom, from unknown causes.

Conclusion

Of course, to lose a light on the road is no worse than running out of batteries mid-ride, which is all-but-completely avoidable with a USB-rechargeable light. As long as one is diligent about charging the Boomers regularly, if not frequently, they'll serve you well.

And to Jonathan's point about the improved electronics, I can honestly say that the Knogs have held up remarkably well in the face of my near-daily (ab)use, from simply attaching and removing them to putting them to the test in harsh road and weather conditions to practically sitting on them. Some might say a super-stiff aluminum frame is less-than-ideal for anything but the velodrome (I, for one, am willing to sacrifice the comfort for the handling advantages any day), yet the Boomers have remained reliable despite the largely unmitigated rattling and vibrations of the unforgiving asphalt of NYC.

In fact, I would go so far as to say that I now find bicycle lights as essential as a helmet—sometimes more so, at risk of backlash—for night riding. While I can't say that I've used anything but Knogs as my lights of choice, much less other USB-rechargeable offerings from Blackburn and Cygolite, I would recommend them with the caveat that they are prone to replacement. I'm happy to report that the new enclosure is without issue and I've been using the Boomers as much as ever despite the dropping temperatures (though I must admit that I've been considering Bookmans as a smaller backup option...)

But this is precisely Knog's strength: there's no denying their commitment to refining their product, and the company's willingness to compensate for their shortcomings with excellent customer service is matched only by their openness to customer feedback. I'm sure Jonathan and the entire team would appreciate any questions, praise or criticism in the comments.

Who knows, maybe the next generation of Boomers will be the ones that ultimately outlast your bike, like a broken-in Brooks saddle, Phil Wood hubs or Campagnolo seatpost... In the meantime, I'm glad to see Knog forge ahead with innovative new offerings within the bicycle safety and security category, and I'm definitely excited to get my hands on the "Strongman," their take on a U-lock.