Garmin Varia RTL515 Review – brilliant & meh

Garmin Varia RTL515 Review

Garmin today announced the Varia RTL515 which is a modest update on the Varia RTL510 radar taillight and also the wholly new Varia RVR315 which is intriguingly just a radar unit without a light.

Garmin Varia lights are those brilliant accessories that you never knew you either needed or wanted…until you actually bought and used it every day thereafter


Varia RTL515 and Varia RVR315 – What’s new?


car approach warning

The Garmin Varia RVR315 is a new product. More on that in a minute, for those of you looking at what’s new on the RTL515, it just seems to be this

  • Peloton Mode: RTL515 offers an ANT+ only mode that provides low-intensity light that is kind to other cyclists’ eyes.
  • Improved Mounting: Varia can now be mounted to D-shaped, aero, and round seat posts.
  • Optimized Battery Life: ‘Up to’ 16 hours in day flash mode, 6 in solid for RTL515, and up to 7 hours for RVR315
  • BLE Support

These are small but noteworthy improvements (as they all affect me 😉 ). Whilst fellow peloton members can pair to your Varia to share in your vehicle warnings, the reality is they won’t and all your fellow cyclists will do is moan that your light is too bright…not now with PELOTON MODE.

I have a Cervelo R5 and the old mounts simply do not properly work on the D-shape cross-section of my seat post. Now they do. Although I STRONGLY recommend getting a proper seat post bracket (or similar) rather than trusting your very expensive light to a single elastic band.

….and you get an extra hour of juice. Maybe.

BLE Support ?!? Sounds rubbish, right? Read on.



Garmin Varia RTL515 – The Meh.

Let’s say, like me, you’ve already got an RTL510. What’s the point in forking out another small fortune for a near-identical upgrade? The battery life is claimed to be a bit better. But is it $200 better? Probably not. That’s my argument for NOT buying the RTL515 as an upgrade to the RTL510.

However, as brilliant as the RTL510 is, it DOES run out of juice too easily. It is my single-most annoying product in that regard. The RTL510’s battery life in day-flash mode is supposedly 15 hours – with the new RTL515 having a claimed 16 hours. 15 hours may have been the case at launch for the 510 but I now get nowhere near that amount and I would say I’m lucky to get 10 hours. So if you couple two 4-hour rides with forgetting to turn it off after the first ride then, towards the end of that second ride, you always get the annoyingly-useful LOW RADAR BATTERY warning popping up. This is mainly a ‘user error’ caused by me not charging up the RTL as often as I do my bike computers, yet I’d say I’m generally good at keeping my things juiced up…just not with the Varia.

Long story short….it might be worth getting the RTL515 for the extra hour of improved battery life and perhaps a brand new battery rather than one that might have been sitting in a Garmin warehouse somewhere, degrading slowly for the last 2 years 😉

However, if you’re going to buy your first Varia DEFINITELY get the 515 and, maybe if you’re contemplating upgrading then just think about the potentially better battery a little bit longer.

Garmin Varia RTL515 – Brilliant

The RTL515 now offers BLE connectivity when previously it was ANT+ only

“What the…?!?” you say. “Why is BLE brilliant?” you add.

Here’s why.

This is a commercial mini-masterstroke by Garmin. The reason is that now smartphone apps can support Garmin Varia radar. So this opens up a whole new market segment for Garmin ie riders who record their rides with apps, not bike computers.

Let’s face it there are quite a few ‘serious’ cyclists who don’t even wear helmets, yet I’m betting that everyone that uses a smartphone bike app to record their ride wears a helmet and are generally a safety-conscious lot. So let’s increase that safety with rear-facing radar alerts and smartly flashing lights to warn vehicles of your presence.

This partly explains the keenness of Ride With GPS (RwGPS) to get in on the act to support the RTL515 as from NOW. They have a great chance to sway over even more STRAVA app users who previously recorded their rides with STRAVA but who have gotten increasingly annoyed as STRAVA removes external sensor support. Jeez…RwGPS even supports power meters!

Fun Fact: RwGPS have never had VC funding. #Kudos


Garmin Varia on Bike Computers

My super-detailed review of the earlier Varia RTL510 is in the link that immediately follows, is a good place to see, side by side, how the implementations of Varia subtly differ from one bike computer manufacturer to another – or you could just look at the image above which is a bit quicker 😉

Not Worth It – Garmin Varia RCT715 Review…but..

AFAIK none of the non-Garmin bike computer manufacturers supports the ability to use PELOTON mode, although Hammerhead said they will at least look at that shortly.

Garmin Varia on Smartphone Apps…well, RwGPS

As well as the Garmin Varia RADAR app, Garmin has partnered with RwGPS for smartphone app integrations with the new BLE-enabled Varias. Here we have some screens from RideWithGPS which shows what looks to be a generally well-thought-through implementation.

OK, some of the voluminous screen real-estate is lost to the Varia bar at the side but that would be a trivial criticism when you compare the awesomeness of how RwGPS looks on screen compared to probably any dedicated bike computer. I hate to admit it, it even looks prettier than the Hammerhead Karoo here 😉

The RwGPS sidebar for Varia even gives information on how far behind approaching cars are if you look closely.


RwGPS claim that one of the key innovations that the smartphone app platform has allowed them to make is the introduction of cleverer audio alerts including, for example, to make a special audible warning for RAPIDLY approaching cars and for when the danger has passed. #Maybe. The argument makes sense I’m sure in some scenarios, however, in other scenarios with busy roads, I know Varia users disable the volume to stop annoying permanent audio alerts.

car markers, distance markers. And I think GREEN = there are cars. Hmmm


Garmin Varia RTL515 & Varia RVR315 Key Specifications

The RTL specs are little changed from the RTL510. Similarly, the German version was the RTL511 and is now the RTL516 and that just has the flashing light disabled to comply with German law.

Here are the key specs

  • Max Claimed Battery Life – RTL515 (16 hours), RVR315 (7 hours)
  • Car Detection Distance – Claimed 140m
  • Connection – USB (charging), BLE, ANT+
  • Light Visibility Distance – Claimed 1500m/1 mile (RTL515)

Here are the rest for the RTL515

  • Modes: solid, peloton, night flash, day flash
  • Battery Life – Up to 16 hours (6 hours solid, 6 hours night flash, 16 hours day flash)
  • Lumens: 20lm solid, 29lm night-flash, 65lm day-flash (Contrast to Bontrager Flare R – 65 Lumens with 2km visibility, 270-degree angle)
  • Dimensions: 98.6 x 19.7 x 39.6 mm
  • Weight: 71.0 g
  • Visibility – 1 mile
  • Side visibility – Yes
  • The angle of light visibility – 220 degrees
  • RADAR Angle – 40 degrees
  • Charging cable – Micro USB
  • Communications – ANT+, BLE
  • Vehicle detection – 140m/150yards
  • Compatibility – Garmin Edge, some Garmin Forerunner, Hammerhead Karoo, Stages Dash, Wahoo ELEMNT (check, some smartphone apps eg RwGPS
  • Water rating: IPX7
  • RADAR detects 8 vehicles
  • Approach speed detection – 10 to 160 km/h (from 6 to 99 mph)
  • Alternative mounts eg saddle/saddle-bag mounts: Check

Garmin Varia RVR315 – aka the intriguing one.

I mean…why? A radar and no light? Surely the whole point is to stop those fast-moving chunks of metal (cars, lorries) from whacking you from behind?

Well, yes. But Garmin did introduce this for a good reason, or two, although I’m not sure if the RTL315 will justify itself on these 2 grounds, in the market. Here’s a very exciting series of images of the RVR315 and the Garmin Varia Radar app that you can use with it on your smartphone.

I’ve used the RTL510 a LOT and one of its benefits is that you can glance down at your bike and see a car approaching from the rear, indicated on your Garmin Edge/Garmin Forerunner/Wahoo/Stages/Karoo bike computer. Thus it gives you a heads-up to determine if you have to perform a heads-back look back over your shoulder before moving out for some reason. OK, I get it, YES you still have to look over your shoulder but if Varia says there are 5 cars bearing down on you then you might just decide to stay where you are rather than even think about attempting a manoeuvre.

So let’s say you’ve already invested in some cheap flashing light for your own safety, then the RTL315 could be a nice little upgrade for you to complement your existing lights. The RVR315 will give you some rear-view intelligence.

I’ve not convinced myself with that argument, so I doubt I’ve convinced you either!

Thoughts & Opinions

Jeez, these are expensive. I mean really expensive. Is your life or your partner’s worth Eu200? A: Probably


  • If you have an RTL510 then don’t upgrade unless you haven’t bought anything for your bike for a while.
  • If you have a compatible smartphone app then go for it
  • If you’ve already got smart lights then think about the radar-only model
  • The Forerunner 945 (or any other supported watch) works reasonably well. I have mine set up and mainly use its audio alerts when working with a karoo that has no sound. if you have your watch on the handlebar that would work ok too but on your wrist, the visual alert is not so easy (and safe) to use. See the image further above
  • The Wahoo BOLT gets frequent dropouts to Varia (RADAR Disconnected), which is a PITA. Say, once or twice an hour.
  • See comments below that RADAR-only usage is not possible with the RTL515


RTL515 Pricing & Availability

Pricing is a little on the high side. On a positive note, these high prices will enable deeper discounting on the earlier RTL510, at least until stocks run out.

  • RTL515 – Eu199
  • RVR315 – Eu149

The following links to all Varia products sold at key retailers. The RTL515 should appear once the retailers correctly list it.

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37 thoughts on “Garmin Varia RTL515 Review – brilliant & meh

  1. version without light and only 7h is a joke. version 515 almost the same as 510. I’m very disappointed. no one writes how long the radar with the lights off will last.

    1. i’ll add it in if i can find it i guess same as rvr, i cant even see that spec on garmin’s site. not sure many will buy the RVR

      i had hoped for more

    2. ArT – the annoying thing is the radar function won’t work with the light off. Even if you use a Garmin head unit to turn the light off that will also disable the radar function. Why they’ve done this is sooo stupid. As I would happily use my existing lights and a radar with >16h battery.

      1. hmm. i thought that was possible on a garmin (just what i thought not what i knew). thank you for the heads up on that, sounds crazy. surely the radar battery would last a long time if such a scenario worked

      2. Dean – My colleagues use radar without light in 510. So this option lasts about 20 hours. I have a video but I can’t post it here.

      3. I already know, unfortunately, only with garmin you can turn off swaitło through the application. There is no switch off light option on the radar button. I don’t understand why garmin did that.

      4. tfk, the5krunner says: “there could also be a further option of ‘no light unless car movement detected’ – There is no such possibility, OFF only. 20H friend test works. (RTL510)

      5. I think garmin will never introduce this option, why? Because the radar is not 1000% sure to see the car. There is certain death at night.

      6. at night, i agree. but if you’ve got a light you’ve got to use it at night
        set against that a 1 hour remaining battery for a 2 hour night journey

  2. Hi, do you have any suggestion for a “proper”/“solid” support for a v-shaped seatpost?
    I quote you, I don’t trust a single elastic band 🙁


  3. I had the first gen, and just purchased the 510 (great timing).

    In both cases, I was most disappointed in the inability to get an audible alert (your cycling computer beeping doesn’t really count, as it’s not loud enough to be heard).

    Nobody has mentioned it as an upgrade reason in reviews, but I’m seriously thinking of getting it just because the 515 offers alerts through a phone app. I use bone conduction headphones to hear the navigation alerts. These are great as they block NO ambient sound, but I can clearly hear alerts from the phone.

    Does anyone know if I’m just missing how to get the audible alerts from the 510 ?

    Since all reviews indicate it’s a “meh” upgrade from 510 to 515. To me, being able to get my attention is a huge upgrade. The cycling computer display change is fine if you happen to look at the computer, but it’s not safe to ride along watching your computer, and the change is not significant enough to trigger my attention from my peripheral vision.

    1. OK that’s a great question and the answer depends on your bike watch/computer.
      – something like a garmin 945 can pair audio to your earbuds and you should get teh alerts that way
      – RwGPS specifically majored on the idea that someone like you might have a smartphone in their back pocket and you can use their app and the earbuds linked to your smartphone
      – RwGPS also have tinkered with the audio more indepth than the other tech that supports rtl510/515 and so might provide a better audio experience. #NotTestedByMeYet

    2. Mike

      Had exactly the same issue beung unable to hear the audio beeps on the RTL510.

      Did you get the RTL515 and is the audio via headphones good?

      Thanks in advance


      1. Using the Garmin app that pairs with the radar, and wearing AfterShokz solved the problem for me. The Aftershokz are tremendous. I can get feedback from my phone with NOTHING blocking my ears for situational awareness.

  4. Is the RTL515 the same hardware as RTL510?
    I hope Garmin provide a firmware update to the RTL510 to include peloton mode?

  5. Not sure why wouldn’t they include a basic camera. Would make sense to have video-proof and radar data at the same time.

    1. that’s a good idea in principle but it becomes hard to keep both bits of tech up to date
      xplova incorporated video into a head unit but by the time it got to market is was behind the curve of standalone gopros and the like. that said, radar/light tech is a bit easier to keep up to date than a bike head unit.

      1. One reason is that you need space for the radar, another space for the LED and then another space for your theoretical camera…making this thing…lonnggggggg

  6. Can you connect to the Garmin Varia app on your phone through bluetooth and a Garmin head unit by ANT+ at the same time? I would like to get the visual alert on my Garmin Edge while also getting an audio alert through my headphones through the phone app. Do you know if this is possible?

  7. Just got the 515 and it works when connected to a USB power source, therefore almost unlimited time on.

    Was that the case for the 510?

    If not, then this is probably a significant selling point for certain cyclists.

    1. same
      i was thinking about this the other day and someone will have to invent a bike battery that powers all our gadgets (di2,computer,varia,pm). although it’s probably called an electric bike. it could mean a much more compact head unit tho and then the need to invent power management profiles

  8. A radar without a light is just what every Fly6 user would want. For me the Fly6 is a must, a radar if it can fit so the smaller RVR315 is what I’ll probably get

  9. I think the elephant in the room is that this thing doesn’t tell you if a vehicle is about to grind you into the asphalt or pass you. And whether or not it’s the former or the latter, who cares the speed – I don’t to be hit, period. I’m not exactly OK with an impact if it’s at slow speed. If you live in a city that thing is gonna be blasting warnings at you all day because – newsflash, there’s cars everywhere. And if it blasts warnings at me in the countryside much less often, the question has to be asked – what am I supposed to do about those warnings apart from live with additional anxiety…an evasive manoeuvre like mount the curb every time it sounds? It’s going to be a huge overreaction in all but 1 in many thousands of times when the driver didn’t see me. Look over my shoulder and probably swerve into their path when they were going to pass me anyway?
    My feeling is that this will be an incredible technology once refined to the point of it being able to predict a vehicles dangerous line or path in combination with speed but it will need a camera for that.
    Convince me I’m wrong.

    1. i can’t argue with that.
      however i would say that there are scenarios where it just gives you more info…you can ignore the info or not. (eg before i pull out do i look to see if there is a car behind…ah no…the radar says there IS one, so I don’t look over my shoulder and maybe swerve out a bit)

      i think many people (me included) are sceptical until they get one.

  10. With this new varia rtl515, do you think we will see a new Garmin front light to replace the ut800?

  11. This is the best bit of safety kit I own. It just works. I have the radar-only model (already had a good rear light) and use an Edge 130 – the simplest cheapest Garmon on the handlebars. It never misses a car or a bike. It bleeps once to attract my attention and shows the car approaching. Absolutely invaluable. If you ride mostly on roads this is must-have kit. `they should build this into bikes in the factory – like seatbelts and airbags I predict it will be compulsory

    1. yep! what the battery like with the radar-only.
      my gripe with the light+radar is that I get maybe 3-4 rides worth of usage and then need to recharge it. I would guess the radar only lasts much longer

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