If you ride your bike in traffic, be it for commuting, fun, or fitness, likely you’ve had close calls or have been nervous at some point even if you haven’t actually had an incident. Bike radar devices — usually in the form of a tail light — can help make you safer — or at least feel safer — on the road. Garmin makes many of these devices under their Varia banner. Put the device on your bike and it alerts you as traffic approches, both with an alert on your device and a sound. The Garmin Varia RCT715 takes this a step further — taking a video of the approaching vehicle.
I have a hard time giving stars or a numerical rating to a product. Doing so becomes easier when I’ve written several reviews about competing products. As this is the first time I’m reviewing a bike radar item, I just set up the review starts with my feelings about several salient areas in regards to the device. Sometimes it would be easier to give a product a simple “thumbs up” or “thumbs down.” As I’ve continued to use this device and put it on whatever bike I ride, now, this one deserves a thumbs up.
During this review, I’ve added a few short video clips to give you the idea of how some of the functions appear on different devices. Perhaps I’ll combine them into a full video review someday, but today isn’t that day.
If you’re interested in other bike radar devices that are available, we wrote a post about all of the bike radar devices that we know of.
This post may contain some affiliate links, which means if you click a link that is an affiliate link and make a subsequent purchase, we may get a small commission that goes toward running this website.
Table of Contents
Garmin Varia RCT715 Areas Rated
Rate and Review
Here’s our overall ratings. Click the “users” tab to review it yourself. You can also leave a comment to register your opinion.
Let’s look at the areas I discussed in the rating stars:
Reliability
If you’re using radar, you want your device to be reliable.
In terms of remaining connected to my device, the Garmin Varia RCT715 has been very reliable. Once set up, it was easily found by my device and turns on and stayed connected to the device — unless, of course, I let its battery run out.
As far as reliability in detecting oncoming cars, it’s also been pretty spot-on, at least with its yellow-zone detection of upcoming cars. There’s also a red zone for cars that are approaching quickly and seem like a danger. This has not been quite as reliable, more on the side of false positives than with any false negatives. Sometimes I cannot see why it thought the small car was a red-zone threat but not the huge truck that came too close for comfort and left me with a gust of wind in its wake.
But I’d never 100% trust my safety to an electronic device. I consider this a supplement to safety and not a replacement for both my mirror and a visual check.
Price
With its $399 price tag unless you happen to find it on sale or buy it used, this is the most expensive of Garmin’s Varia units. You’re paying for the extra video features, here.
The widget below should show the current price on Amazon.
- See and record what’s behind you with a built-in camera that saves footage automatically if it detects an incident
- Capture sharp, clear video in 1080p at 30 fps, or set resolution at 720p to extend battery life for longer rides
- Easily view footage and control the camera via the Varia mobile app
- Automatically detects incidents and saves footage before, during and after events if it detects an incident
- Rearview radar detects vehicles approaching from behind up to 153 yards (140 meters) away and integrates with your Edge bike computer, select Garmin wearables or the Varia app on your paired compatible smartphone to provide alerts
Ease of Use and Installation
If you have a bike with a standard seatpost and don’t like to pile stuff on top of a rear rack, installation is very easy: just use the silicone straps that come with the device and fasten it onto your seatpost.
However, if you use a dropper post or you like to pile stuff on a rear rack that will block the device, you may need to get creative.
Other Garmin Varia devices use the same quarter-turn mount as Garmin Edge bike computers. Not so the Garmin Varia RCT715. It’s a heavier device that has its own mount with a push-down lever to secure it. And with my rear rack and dropper post, it was more difficult for me to find a way to install this where it would both both be high enough from the ground and not at an angle.
Read the post about how I got just a bit creative with installing the Garmin Varia RCT715.
Improves Safety?
The big question, here, is whether having a radar device on your bike actually makes you safer. Or does it just make you feel safer? Certainly, if a car veers off and hits you, there may be little you can do about it. I tell myself “well…at least maybe they’ll have a video so they know what happened…”
As I said above, I consider this a supplement to safety, along with a mirror and visual checks. I’m not exactly young anymore. For years I rode a drop bar bike without any mirror and was fine but, lately, I have some mild shoulder and neck issues. I still do a quick check before I move over, of course, but having a mirror and the radar device makes me more confident in my checks before moving over. I also find myself moving even more to the inside of the shoulder, if I have room, when it senses an upcoming vehicle.
In a quick search, I didn’t find any studies on the efficacy of bike radar devices, the same way I found evidence that, yes, wearing neon yellow DOES make you safer and more visible to traffic. But my feeling is that the device does improve my safety, at least by a margin. And anything helps.
Garmin Varia RCT715 compatibility with different devices and apps.
Here’s one of the device’s limitations. If you want to use a Garmin Varia device, you have a few options:
Garmin Varia app
The Garmin Varia app pairs the Varia device to your smartphone to alert you of approaching vehicles. You can also use it to control the camera or, theoretically, to view videos. However, I found that when viewing videos on the app, most were “locked,” and none would actually play unless I downloaded them first.
And here’s what I mean by download: it puts them in the “download” folder in the app. From there, there’s no link to actually download the video to your device.
Below is a brief video of viewing photos and videos on the Varia app. Once I reach the “downloads” folder, that’s it — there’s no link to actually download that video to your camera roll.
If you want to get videos off the device and save them on your computer, the best way is to plug the device into your computer, and you’ll then find them in the Garmin folder to save to your heart’s content.
Garmin Edge Cycling Computer
If you use a Garmin Edge cycling computer, you can also use that for alerts and for controlling your camera as well as the bike light modes. You can’t of course, view your videos on the device.
In the video, I had just turned on the device but even though it said that a light network was not formed, as you can see it was giving feedback. After you turn the device on and wait for a few it will say “light networked formed.”
Ride With GPS
I love Ride With GPS and use it with the Garmin Varia RCT715 for most shorter trips and rides, and I prefer its feedback with the Varia over that given by the Garmin Edge or the Varia app.
Using GPS on your phone, though, does suck the battery, so for longer rides I tend to use my Garmin Edge. One of the limitations of Ride With GPS is that — at least at the time of this writing — you cannot control the camera with it, as you can with the Varia app or the Garmin Edge. Nor can you control the light modes of the Varia. You’ll need to choose your light mode manually before you start your ride.
For the most part, though, I haven’t been actively controlling the camera, just trusting that the camera would take a video if there was an incident. Still, it would be nice if they could somehow include the ability to take a photo or intentionally record video with the camera as the only time I’ve had connection problems with the Varia is if I attempted to connect two devices at once. And, in my opinion, the Varia app leaves a lot to be desired but is pretty easy to use for snapping a photo or video and the Garmin Edge is cumbersome when it come to using the camera controls.
When I recently looked at the videos on the device, I had many from 2023…but none from my more recent 2024 rides. So, perhaps, I do want to clear that card occasionally and perhaps I do want a way to control that camera when I’m riding.
Cadence
I have not used Cadence, and so I do not have a video here, but it appears that, as with Ride With GPS, your feedback is both sound and a little line on the side with a car on it that turns yellow, red, or green depending on approaching traffic.
Does my Wahoo bike computer work with the Garmin Varia RCT715 ?
I do not have a Wahoo bike computer and it used to be the case that they were not compatible. But, now, you can pair your Varia device with their Elemnt computers using Ant+. I don’t have an example of the feedback provided by the Wahoo as I don’t have their Elemnt bike computer.
Battery Life
The life of the battery in the Garmin Varia RCT715 really depends on how you use it. If you use it with the light on solid and the camera on it will, of course, use the battery much more than if you turn the camera off and keep it on day flash mode.
This means that for long rides, you’d want to turn that camera off and have it in day flash mode — you might get 10 hours out of it if you start with a full charge. Garmin suggests that the battery life is four hours with solid on and camera enabled.
It also might eat up more of the battery life in the device to which it’s connected. On my ebike, I can just plug the device in to the bike to maintain power, or (theoretically) into my dynamo charger on my non ebike. I say this theoretically here as I just hooked up the thing and am trying to determine if I actually have the thing working.
But when it comes to a taillight, I can’t really plug it in on the fly. Unless, I guess, I had a power pack back there and a cord coming out of the bag. But having things like that behind me makes me a bit nervous and my only bike mishap occurred when I thought something had fallen out of a jersey pocket and I looked back to check.
Tail Light
With all of its other features, I almost forgot that the Garmin Varia RCT715 is also a tail light and not just a radar unit! The tail light has four modes that you can cycle through by a push of the button after turning on the device or by using the Varia app or your Garmin Edge device. As I noted before, you can’t control the lights within the Ride With GPS app.
Solid mode is 20 lumens, night flash is 29 lumens, day flash is 65 lumens, and there’s an 8 lumen “peloton mode,” so, I guess, you don’t blind your fellow riders. There’s not an option to have the light entirely off and still have the radar on. I have another rear light on my bikes, but I guess one more light doesn’t hurt.
I think that if the Garmin Varia RCT715 were my only light and I did much night riding — which I don’t — I’d likely want another, brighter, light to increase visibility.
Weight
Compared with Garmin’s other bike radar devices, the RCT715 is a heavyweight. But I’m no longer (much) of a weight weenie as I’m riding for fun, fitness, and transportation these days and not trying to race.
Based on the data on their website, here’s a breakdown of the weight of their various radar devices:
Garmin Varia RCT715 | 5.2 oz (147.0 g) |
Garmin Varia RTL515 | 2.5 oz (71.0 g) |
Garmin Varia RVR315 (radar only, no light) | 1.8 oz (51.0 g) |
Garmin Varia eRTL615 | 1.8 oz (50.0 g) |
Garmin “Rearview Radar” (includes light and a head unit) | Radar display unit: 1.0 oz (28.5 g); Tail light: 2.2 oz (63.5 g) |
“Additional Features”: The Camera
The special feature of the Garmin Varia RCT715 is its camera. The camera, from what I read, is continuously recording, but then saves a video if it detects an incident. You can access recent clips from the device by plugging it into your computer or by using the Varia app.
The best way, again, to view photos and videos is directly from your computer. The Varia app is, mostly, ok just for a quick viewing of the videos.
I haven’t had the chance, fortunately, to test the feature that saves a video during an incident.
You can’t expect the video from a device like this to be GoPro quality. This isn’t intended to be a high-quality video for your YouTube fans. This is for having proof that the idiot knocked you off the road into the ditch or worse.
But is it legal to record following cars? In the US, if you’re on a public road then, yes, it is legal to do so. From what I read, the Supreme Court has established that in the public space there is no expectation of privacy. So, yes, it’s legal here in the US to take videos with a Garmin Varia device. If you are worried about this, you should consult the laws for your country.
Below is an example of a video I downloaded from my Garmin Varia RCT715 during some errands. Wide-angle footage, shaky — of course — because it’s on a bike.
Summary
For me the Garmin Varia RCT715 has been quite a dependable device. It’s just a bit like having eyes in the back of my head, making me feel safer on the road. However, I’m not sure if I need the video feature. But if I ever do have an incident, perhaps it will be helpful. Maybe it would help to have a sign on my bike saying, “You are being recorded!” Whether that would encourage better or worse behavior from drivers, I’m not sure.
Bike Radar Poll
Below is a poll about your experience with bike radar devices in general.
If you’ve used the Garmin Varia RCT715 specifically, what has been your experience? You can leave feedback here or leave a comment below.