I’ve already had 3 relatively quick rides with the RTL 500 (and the Edge 820).
It’s a compatible accessory for top-end Garmin Edge devices that provides a rear light and radar-based alerts to your Edge.
It works surprisingly well with the latest firmware.
Must Read: Garmin Varia RCT715 Review
When a vehicle approaches from over 100m away your Edge beeps and a little dot appears on the right-hand side of the Edge’s screen. As the vehicle gets closer the dot moves higher. I think the rear lights also flash more quickly to the vehicle as it gets closer as a warning.
It does seem to detect most vehicles but not all. Multiple vehicles ARE detected although sometimes a second vehicle close to the first is missed.
I have used it in light traffic (perfect) and medium-to-heavy (good). But I don’t commute to London much so I’m not sure how it would cope with an increased and permanently high level of traffic.
I have had issues with the sensor losing a connection intermittently. No doubt further firmware updates will eventually rectify this.
I might give it a go in the Pru Ride London on Sunday. Apparently, the RADAR will not detect bikes. With several tens likely to go past me (OK hundreds) then this will be a test to see whether the RTL 500 keeps annoying me with beeps for a whole 100 miles. Or I might not take it, just in case.
I got the impression from questions to a Garmin staffer that sales of these are not super high BUT sales are sufficiently robust that Garmin is continuing R&D on evolving the product line.
At £140 (UK Link) and US$200 (US Link), these are not cheap. On the other hand, how much is your life worth?
You might think of buying one to protect your kids but the reality is that your kid wouldn’t have an Edge 820 is almost every case. So, instead, you might have to buy one for your partner and their commute to work 🙂
This is a loan item from Garmin. I probably wouldn’t buy one myself as I tend to avoid cars where possible. It only takes one car though.
Last Updated on 20 May 2022 by the5krunner
My favourite kit and nutrition
- Maurten — the race nutrition trusted by elite athletes. Gels and drink mix engineered to be easy on the stomach.
- Garmin 90-degree charging adapter — the small adapter that keeps your charging cable tidy at the stem. Essential for race day.
- Garmin charging puck — the fastest and most reliable way to top up your Garmin before a session.
- Ravemen FR300 — front light that mounts directly under your Garmin or Wahoo head unit. Keeps your bars clean and your beam pointed where it matters.
- Garmin Varia RTL515 — radar rear light that alerts you to vehicles approaching from behind. Pairs with your Edge or Garmin watch.
- Stryd — the footpod that brings running power to your Garmin. The single most useful running upgrade I have made.
- Favero Assioma Pro RS2 — the power meter pedals most serious cyclists end up choosing. Accurate, easy to move between bikes.
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. ID
it’s peace of mind for me to have it out on rides where you need to cross several lanes. I would say the battery life isn’t great. other than that i enjoy it.
Except that the battery life could be better, it works really well for me and gives me more freedom while riding my bike.
Especially on roads where traffic is not constantly there, it gives me the freedom to ride not very close to the edge of the street without having a bad feeling about being an obstacle for suddenly approaching cars. It detects bikes, but only when they approach fast enough. When there’s a lot of wind or in winter time, when you can’t hear approaching cars, the radar does it for you. On fast hilly decents you always have the advantage of knowing if (and how many) cars are behind you.