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Kranx Shard 100 USB Rear Light
29g (inc. bracket) £9.99

The Kranx Shard 100 Rear Light is a stripped-down model with a number of really likeable features. OK, it doesn’t feel as robust as some more expensive models and it may not have the raw punch of others. However, at this price point, it is worth asking how much punch and how much strength you require or should expect. I’ve found it effective on commutes either side of dawn, and on late night rides home from the Temperance Reading Room. There’s a lot to be said for it, and not just as an entry level light.


Pros: light, cheap, sensible modes.


Cons: prone to unintended activation in some circumstance.



The Shard is a slim-line, coffin-shaped light. Inside the black plastic back-plate and the red casing are the LEDs and a 200mAh Li battery, plus, of course, the Chips on Board which control the functions. The casing projects from the base, spreading light to both sides. The switch, more of that later, occupies the very top section of the light. There’s the ubiquitous USB charging point, safely covered by a flap that pushes firmly home. An overall IPX4 rating means it should be fine n rain – just don’t chuck it I the canal.


The body of the light is not separable from the bracket: well, it is, but it is hard to know what you’d do with the light if you removed it. The screw is covered by a sticky pad to protect your posh seat-stem or other mounting-point from scratches. There’s a charge indicator above the switch.

Seven Day cyclist Kranx ear bicycle light

My first reaction on opening the pack was that the light felt a bit ‘plasticky’. No surprise really, given the price, and, in fairness not necessarily a bad thing. However, it did feel very light. Unlike some more expensive brands, there’s no suggestion that you’ll get away with dropping it from a height, nor is there an indication of its waterproof credentials.


Of course, there’s a USB cable for charging. The instructions on the packaging are easy to follow, not that this is such a complex beast as to tax the brain to harshly.

Bicycle cycle rear light recharge Kranx 100 Shard

Charge, run times, and modes 3/5


Charge times have varied quite widely. Expect three hours or so on the mains, but a bit longer through a laptop. If you need a sneaky charge in the office or at the workbench for the commute home, best plug it in to the company computer sooner rather than later.


There are six modes – plenty for me: three steady and three flash. At the top comes the 100 lumens with a run time of two and a half hours. The max run-time for, what I’ll call, eco, is ten hours.


Frankly, the latter does not match the thirty hours available on some pricier models; and you’ll get more lumens and longer run tomes at the top end, too. For example, my old favourite, the Ravemen TR300, which boasts excellent run times and a frighteningly bright top end. Mind you, it can hardly be described as an entry to mid-level light. Mind you, the Kranx Strix has longer run times, too.


The official run times are; steady low 25 lumens 10 hours, medium 50 lumen 5 hours, high 100 lumens 2.5 hours; flash low 10 hours, high 8 hours, strobe 6 hours. These generally seem to be pretty accurate. In the real world you may well change modes within the same charge period. For me, I’ve manged four days of commuting (roughly an hour each way).


The charge indicator is not the easiest to spot, at least in the first place. If flashes during charging, eventually turning solid. There’s not a whole lot of warning when charge foes low – after all, the light is probably out of sight under your saddle. Nor does there seem to be an SoS get-me-home default.

bicycle light rear cyclist mount strap

Bracket and mounting 3.5/5


The light comes fixed to the bracket by a small Phillips screw. It’s a watch-strap type which shoud secure the light to all but the thickest seat posts and thinnest stays. The bracket itself feels very solid: the rubber strap is nice and thick and the hook feels secure. Easy to portbetween bikes or strap on in an emergency or for additional light.


The screw fixture allows rotation of 360 degrees in the vertical plane. I like this flexibility of positioning. I’ve mounted it on the seat post of tourer and commuter/utility machines. Given the short length of exposed seat-post of the latter, turning the light horizontally made sound sense. Even better, the base-plate stands a little proud of the bracket allowing it to clear the lip of the tube and the clamp bolt.

Switch 3/5


The switch is a large rubber pad, easily locatable and easily operated, even in winter weight gloves. Activation takes a firm push. A single click for steady and a double click for flash. Turn off with a push and hold. This works easily, and the switch is large enough to be operated on the fly – provided you can reach around to the seat post and keep control of your bike. On the other hand, I have found occasional pocket activation or discovered the light flashing at the bottom of the pannier. The latter was carelessness, but take care when carrying around away from the bike

Performance 3/5


Well, I’ve used this as my go-to light for four weeks of mixed riding; commutes either side of dawn and dusk, a couple of late-night returns along country lanes from social occasions, and as a day-time runner in dark, stormy weather.

bicycle light rear seven day cyclist

Early morning, I’ve generally used the medium steady mode. Fifty lumens has been easily visible to the meagre number of road-users around at 5.45 in the morning. There’s clarity at around sixty metes, I’m told, and awareness well before that. I’ve upped it to the hundred mode for the final couple of miles on slightly busier city centre roads, as the sun has poked its head over the horizon. Flashing mode, generally high, has suited the busier roads of the city centre on evening return journeys. On unlit country lanes, given nice clear conditions, I’d have used 100 lumens mode – if I hadn’t been concerned about running out of juice – so fifty seemed to suffice, giving 50 or so metres of presence, with the full hundred offering eighty to ninety metres – whenever the road was straight enough.

bike cycle light review seven day cyclist
rear light review seven day cyclist

There are better day time runners, and I’d really only use the Shard if push had come to shove. Even so, the high flash or strobe gave decent visibility.


A definite plus is the side vision, although my aged Cat-Eye outdoes it, although this is handy rather than great compared to some slightly more expensive models. There are certainly some more expensive lights that have less peripheral presence. In some ways it put me in mind of the Oxford R75 rear light.


Overall, output is good rather than great, with some similarly powerful lights offering a more intense light – at a price.


Value 4/5


Oxford R75 Rear Light has some similarities, although it is pricier and like its 50 lumens compatriot, seems to pack a more intense light. Both are little pricier


Likewise, the Topeak Taillux; more expensive, longer run times and brighter, but all at a price.


The Kranx Strix is a  fiver or so more expensive, but offers wider mounting options, slightly better run times.




This is a budget model. So, let’s judge it accordingly. Light and, at least adequate, for most circumstances, the output is not as great as some lights (and there’s more to that than lumens), but good enough even for long in the tooth multi-purpose riders like me. Best suited, in my opinion, for short utility journeys and as a spare on longer commute or other rides. The price is attractive, and eases the mind when forgetfully leaving it on the bike when parking in urban areas. Stored carefully, it is a light and easy to port back-up. A good value light, in my opinion.

Verdict 3.5/5: Very good value entry level light.


Steve Dyster




Ryton On Dunsmore

Coventry  CV8 3FH


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