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Moon Alcor rear light



Bright, simple, great battery life and a good mount – just try not to lose the rubber bits

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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Here's a great little rear light that you will find very useful. The Moon Alcor is simple, bright and has a nifty magnetic mount.

Light season again already? Actually, I use a back light almost all the time, perhaps excepting on the finest of high summer days. Bright sunlight, especially when the sun is low and the roads are wet, is not the friend of the cyclist and an attention-grabbing strobe like that provided by the Moon Alcor is a valuable aid to daytime visibility.

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That's how I've used this most of the time during the test period, and it was a bonus that the day-flash mode gives over 34 hours of battery life (I never did find out exactly how many hours because I had to go to bed). Moon reckons that on the low-power single-flash setting you should get 70 hours. That's still plenty bright enough for night riding on dark roads, by the way.

There are five modes altogether: besides the two already mentioned there's a high-power single flash (good for riding under street lights) and two steady settings, which are bright without being blinding. To my tastes, that's plenty and it makes life easy when scrolling between the settings. It also helps that the Alcor remembers which setting you were using last and returns to it when it is next switched on.

Moon Alcor - side.jpg

The single button is in the centre of the light and is big enough to use with gloved hands. Press to turn on, press to scroll and press-and-hold to turn off. That's it. It's covered with a rubber seal that stayed secure and kept the water out. I used this on some mountain bike night-rides, just to make sure it got thoroughly wet and muddy, and it didn't miss a blink.

Charging is via USB, with a simple bayonet at the top (or bottom, depending which way up you hold it). To my mind that's much better than a covered socket, which I find makes it difficult to keep the water out. A wipe with a hanky is enough to keep this clean and working. It's protected by a slide-off rubber cover which is a bit of a slack fit. I was worried about it falling off in use, so kept it pointing upwards and all was well.

> Find more reviews of rear lights here

The mount uses a magnet to hold the light in place. Moon seems to lack the courage of its convictions, adding a twist-lock action as well, but I thought the magnet itself was plenty secure enough and certainly makes it easy to centre the light on the mount should you want to fit it while riding along. The mount is simple, with a couple of sizes of rubber bands to fit various seatposts. Moving between bikes couldn't be easier, though the little rubber wedge between the mount and seatpost is, again, a bit loose-fitting and might get lost.

Moon Alcor - magnetic clamp.jpg

It's a great price too, and overall definitely a light to consider if you want an all-rounder for improved visibility and simple functions.


Bright, simple, great battery life and a good mount – just try not to lose the rubber bits test report

Make and model: Moon Alcor

Size tested: 31x54x18mm

Tell us what the light 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?

Moon lists these features:

Day flash

Ultra brightness red LED

Light mode memory

Magnetic mounting RB-29-R

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

And these:

250mAh Li-Po Built-in

Max. Lumens: 15

Recharge time 2 hrs

Size (W x D x H): 31 x54 x 18mm

Weight: 0.017Kg

Mode Lumen Runtime (hours)

MODE 1 3 8:00

MODE 2 6 4:00

FLASH 1 3 70:00

FLASH 2 8 40:00

DAY FLASH 15 30:00

Rate the light for quality of construction:

It's a tidy unit, apart from the slightly sloppy fit of the USB plug cover.

Rate the light for design and ease of use. How simple was the light to use?

Very simple, just how I like them. Press to turn on, scroll through the functions, press to turn off. It remembers the last setting you used. Easy to operate without looking at it.

Rate the light for the design and usability of the clamping system/s

Moon doesn't seem all that confident in its magnetic fitting, opting for a secondary twist-fit action, but I found it secure and quick to use. And easy to switch between bikes.

Rate the light for waterproofing. How did it stand up to the elements?

Very good, so long as that rubber cover stays in place. Even some trawling around in the muck and filth on the mountain bike hasn't bothered it.

Rate the light for battery life. How long did it last? How long did it take to recharge?

Well over 30 hours on the 'day-flash' mode, and recharges in a couple of hours.

Rate the light for performance:

Bright, with a small but useful number of functions.

Rate the light for durability:

I'm worried about losing the rubber cover from the USB stick, which could result in corrosion. Otherwise, it's keeping the elements at bay.

Rate the light for weight:
Rate the light for value:

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

Easy to fit and operate, even when you are groping around behind you for the button. The light is bright and the functions are useful. Battery life is excellent.

Tell us what you particularly liked about the light

Easy to fit and use, bright, useful functions. Good side visibility. Long battery life.

Tell us what you particularly disliked about the light

The loose fit of the rubber cover.

Did you enjoy using the light? Yes

Would you consider buying the light? Yes

Would you recommend the light to a friend? Yes

Use this box to explain your score

Just a little tweak of a couple of the rubber fittings and this would be a perfect little light for any kind of riding.

Overall rating: 9/10

About the tester

Age: 52  Height: 6'2  Weight: 73kg and holding steady

I usually ride: Cannondale CAAD10   My best bike is: Tomassini Prestige

I've been riding for: Over 20 years  I ride: A few times a week  I would class myself as: Experienced

I regularly do the following types of riding: touring, sportives, general fitness riding, mountain biking

Add new comment


froze | 6 years ago
1 like

The Moon Alcor rear light received 4 1/2 stars with only 14 lumens? HUH??? We had 14 lumen technology way back in the 80's!! 14 lumens is just stupidly dim by todays standards. Yet the See Sense ICON which is the brightest light with a self contained battery on the market gets the same ranking as the Moon Alcor...someone's been smoking the funny stuff! The Moon Alcor should have gotten a 1/2 of a star and the See Sense Icon a full 5 stars.

Ryder | 6 years ago
1 like

You could go on Wiggle and buy LifeLine's very similar looking light set for £16.00 (front and rear) which doesn't have all the niggles this brand name one does.

velodinho | 6 years ago

"... a slide-off rubber cover which is a bit of a slack fit. I was worried about it falling off in use, so kept it pointing upwards..."

"..Moon seems to lack the courage of its convictions, adding a twist-lock action as well.."

"..the little rubber wedge between the mount and seatpost is, again, a bit loose-fitting and might get lost.."

Nah. Ain't happening.

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