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Gemini Xera LED Light System



Bright, versatile light with a host of useful functions & accessories, not the lightest but then it's also cheaper than a lot of its rivals too

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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If you're looking for an all-rounder light that will cut it both on and off road without breaking the bank then the Gemini Xera is definitely worth a look. Gemini are a fast-growing Canadian outfit and the Xera, a single LED light with a 2 or 4-cell battery is their first foray in to the UK market. I've have been testing the 4-cell version and I'm impressed, possibly even dazzled, by the combination of power, run time and value for money on offer.

£150 isn't cheap but you get you get a lot for your money. With most competing single LED lights you'll get a handlebar mount and perhaps a helmet mount if you're lucky. Gemini have included both of these, plus a camping style head belt. On top of the fact that it includes a bigger than normal, 4-cell battery, this light set presents good value for money - there's even a battery extension cable.

Gemini have gone down the battery pack route - which will probably count against it with some - leaving a small aluminum light head which mounts to the bars via a simple rubber o-ring. It is a nicely machined piece, weighing in at 52g. The simple mounting does make installation and removal easy, but it did cross my mind that if you're going to remove the light each ride (commuting and leaving bike outside for example), the rubber could fatigue. An included second o-ring perhaps backs up this concern, although the rubber is 5mm in diameter and didn't show signs of wear during the test.

The helmet mounting is by means of a velcro strap, with handlebar like cylinder for the light head to attach to; simple and does the job. The velcro is a special fine toothed variety I've not come across before, but it means there is no chance of it scratching your head or making your helmet hair any worse. The final mount - the head strap - is just like the many camping head torches you will have seen, with frontal plastic cylinder for the light unit. The battery pack straps to the rear and little nodules hold the cable in place. Again, it is simple and does the intended job well. On the bike, the battery is mounted to the top-tube with velcro. It isn't as neat as an integrated solution and I did have problems finding a spot which wouldn't interfere with my rear brake cable or knees - finally opting for the head-tube instead.

On to the main event: the light. Looks can be deceiving as this little unit packs 800 lumens. Our light comparison chart shows it isn't concentrated on one spot either, the light spreads across your path, just as you want it too - particularly for off road riding. The closest competitor to this is probably Exposure's Joystick and the Gemini provides a much wider spread whilst remaining slightly brighter throughout that spread - that extra spread might put off some people who are going to use this primarily as a road light, but again, you're only going to get in to serious driver dazzling territory if you run it on full power and there is rarely any need to do that on the road. It does means the XERA can be the sole light on your bike, even riding unlit country lanes - or indeed leaving the road entirely.

The Gemini isn't lacking in terms of functions either. You have the usual three brightness levels, a flashing mode, but the neat thing here is that you can tailor the brightness of each of these settings. Levels can be changed from 10% in 10% increments, so flashing doesn't need to be an eye watering strobe effect, it can be as low as 10% brightness if you so desire. This also means you can have a road setting and an off road setting. In most situation you certainly aren't going to need to run this on anything like full power even on unlit roads - that in turn has benefits in terms of increased run times.

Battery level is shown through the illuminated button: green - amber- red, with a flashing red light and self-dimming function when things get really low. The level is displayed as soon as you connect the light and remains even with the light off. A useful feature but in well lit areas it could leave one to mistake their light being on when it is in fact, off. To top off the electronics behind this light, a fading effect occurs as you cycle modes - now they are just showing off.

The beauty of this package is that you are not just getting a light for your bike. With the option of a head strap, the light becomes a much more versatile product. Here's some situation where I think it would be useful: tourers who putting up a tent in the dark, endurance mountain bike racers finding their stuff at an unlit campsite, early morning triathlon starts, the list goes on. It even comes in handy for DIY jobs around the house. Of course, you can't just whip it off your bike after a long ride and carry on using it, like all lights, it needs recharging at some point.

The 2-cell has a claimed two hour run-time, with 4-cells doubling that to four hours (on max setting). I found this to be fairly accurate, lasting around 3.5 hours at full blast including an hour or so on the low setting prior to this. Even after the 3.5 hours, it carried on in its 'get home' mode, which is low power with a pulse of increased intensity every few seconds. The included charger takes around 5 hours to fill the 4-cell.

There's not a lot not to like about this new kid on the block. The price is very competitive, even before you consider all the accessories. It isn't as neat as the single unit Exposure Joystick - the velcro attached battery pack is slightly cumbersome on a road bike but it does offer a full 1 hour longer max power run-time and and of course even longer on the lower power settings, and it is brighter, with a wider spread - if that's what you want. There is a weight penalty compared to the Joystick, which is £15 more expensive. While the light unit is 52g, the battery pack is 245g so a total 300g ballast. Even so, if you are after an all-round lighting solution that you can even use beyond cycling, I can fully recommend it.


Bright, versatile light with a host of useful functions & accessories, not the lightest but then it's also cheaper than a lot of its rivals too test report

Make and model: Gemini Xera LED Light System

Size tested: n/a

Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?

'Bike. Run. Ski. Your light for all activities.'

Initially designed for mountain biking, this light packs a lot of power and a good spread. The head strap does indeed make it suitable for running, skiing, DIY...

Tell us some more about the technical aspects of the product?

800 lumens single LED, 4 hour full power run-time, 52g head unit (battery 245g = 297g), bike, helmet and head mounting, 3 adjustable brightness functions and adjustable strobe.

Rate the product for quality of construction:

Nicely machined piece of aluminium, should take a knock with no side effects.

Rate the product for performance:

Bright and with a strong spread. Quoted 4 hour run-time accurate.

Rate the product for durability:

I could see the rubber o-ring possibly fatiguing, especially on over-size bars. If their customer service is up to what they say, this would be a complementary replacement I imagine.

Rate the product for weight, if applicable:

5 for average I'd say. The unit may be only 52g but once you include the 4-cell pack, the complete set is ~300g. For comparison my Joystick is 82g.

Rate the product for value:

For £150 you are getting a high performance light, that would be good value alone, but all the accessories make this unbeatable.

Tell us how the product performed overall when used for its designed purpose

Well, it can be the main light on your night time rides.

Tell us what you particularly liked about the product

The snazzy programming (adjustable brightness, fading between levels, pulsating low power mode). Anti-scratch (my own trademark) velcro.

Tell us what you particularly disliked about the product

Cumbersome battery pack and velcro mounting.

Did you enjoy using the product? Yes

Would you consider buying the product? Yes

Would you recommend the product to a friend? Yes

Anything further to say about the product in conclusion?

A very complete lighting solution

Overall rating: 9/10

About the tester

Age: 23  Height: 184cm  Weight: 66kg

I usually ride: Orbea Onix (Carbon) - Summer, Orbea Asphalt (Alu) - Winter  My best bike is: Orbea Alma G10

I've been riding for: Under 5 years  I ride: Every day  I would class myself as: Semi pro

I regularly do the following types of riding: road racing, time trialling, cyclo cross, club rides, mtb,


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