Bryton Gardia R300L Rear View Bike Radar Tail Light

The Bryton Gardia R300L is a well-priced and effective radar and rear light combination, pairing easily with my head units and detecting cars from an impressive distance away. There are some small quirks like patchy pick-up of motorbikes and losing vehicles when they're moving at your speed, but overall it's an impressive piece of kit.

Not bothered about the radar? Check out our guides to the best rear bike lights.

The Gardia R300L is effectively a rival to Garmin's Varia radar system, at a lower price. Its purpose is to warn you about vehicles approaching from the rear, but it has a couple of bonuses thrown in too, namely the easy-to-use smartphone app and smart light capabilities.

Though made by Bryton, it pairs with most modern head units, and all of the most popular brands that I use. I tried it with a Garmin Edge 830 and Hammerhead Karoo 2 and both were simple to set up and worked well once connected. As you would imagine, both units have their own ways of displaying approaching cars (Garmin has moving dots on the right, while Hammerhead has car icons on the left), but the radar system worked very well on both.

It tracked well, giving an audible warning and using on-screen visualisations to show clearly how fast approaching vehicles were moving based on how quickly they moved up the screen, and then giving an audible beep and visual 'all-clear' message once the vehicle had passed or turned off.

Like the Garmin, the Gardia also has 40-degree field of view, for detecting vehicles that might be appearing around bends off-axis to your bike, but there are a lot of roman roads where I live, which came in handy for being able to see how effective the Gardia is at detecting over long distances. Bryton says it can detect vehicles up to 150m away, but on these long, straight roads I found it tended to pick them up from about 180-200m, identifying larger vehicles from slightly further away, as you would expect.

Having said it tracked well, it was slightly less reliable with motorbikes than cars, and there were a couple of occasions where I was surprised to find myself being passed by one.

Similarly – as Mike said with the Garmin Varia RCT715 he tested recently – when a car is moving at the same speed as you it would often get 'lost' in the radar, so would no longer appear on the radar visualisation. I didn't find this a huge issue because by the time they are behind you, you're aware they are there, and the point at which they speed up to overtake they get picked up again.

Although not ideal, I think it's understandable, as they would show up as static objects to a radar in the same way a rear wheel or saddle bag would. It would be much more of an issue if it constantly showed something behind you just because you have a bike with two wheels...

I also found that, at this time of year, it could quite often produce errant readings when there was non-vehicular motion behind you. In particular, cow parsley blowing in the wind could cause it to detect a car behind me, and when I looked around there was nothing there. It's not the end of the world and didn't happen too frequently, but it is something I noticed on windy days on lanes with a lot of billowing plants on the side of the road.

Light

As a light it is also pretty effective, with five settings: high, low, day flash, night flash and group mode. (Or you can have it on radar only.) Flicking between them is just a case of a quick press on a single button on the top of the light.

A long press on this same button acts as the on/off switch, but as this is also a smart light that can be connected to your head unit, it effectively turns on and off with your head unit. So you start a ride and the light turns on too; you stop and it turns off. A nice touch.

Smart functions

The light can also detect changes in speed, which means it can act as a 'brake' light that flashes brighter when your speed suddenly slows. As with every other such brake light I've tried, it works okay but isn't perfect, because there is a natural lag between pulling on the brakes and the speed reduction filtering through to the light; it's not instantaneous, as it is on a car as soon as you press the brake pedal, so its effectiveness is debatable.

Another smart function, separate from the brake light, is the flashing light pattern changing when a car is approaching, increasing the chances of you being seen. This feature works through the radar system, which detects the distance a vehicle is away from you.

Both these functions come on automatically when the light is first turned on, but can be disabled or enabled again from the companion smartphone app.

Mounting

Mounting is through a rotational clasp similar to a Garmin mount, which attaches to the seatpost with a rubber ladder strap.

I used this on a couple of different seatpost sizes and shapes and found it held well and didn't rotate or slip, even on flat-backed aero posts.

Battery life & charging

Battery life is dependent on the light settings being used, with a claimed maximum of 17 hours in flashing mode (day and night) and 12 hours in steady mode.

These are broadly what I found throughout the review period. I tended to use the Gardia during the day, so my most common setting was Day Flash, and I only needed to charge it a couple of times over a month of riding.

Charging is via USB-C cable, attaching to a port on the side of the light that has a dust/water cover. Charging takes a couple of hours from dead to fully charged.

A warning light comes on when the unit needs charging, but you can see a more accurate percentage either on the companion app or on a paired head unit.

Value

The Gardia R300L costs £119.99, which is a good price compared with others on the market.

The best-known alternative is Garmin's Varia RTL515, as tested by Iwein last year, which costs £169.99, and to be honest, there isn't a lot to choose between them aside from price.

Dave tested the Magene L508 in January, which costs £5 more and doesn't have the same range as the Bryton.

Conclusion

Overall, I was very impressed by this radar light. It offers the same kind of functionality as the Varia at a much lower price. The tracking is effective and easy to follow, the smart light elements are a real positive, and it's one of those pieces of kit that you can basically just leave on your bike and forget about thanks to the decent battery life.

There are elements that could improved, like tall plants setting it off in a breeze, and motorbike tracking being less reliable than car tracking, but really there is little to complain about. here

Verdict

Impressive radar/rear light system that challenges Garmin's Varia and costs less too