Dear Garmin, just make the 515 with a bigger battery and a USB-C charging port and I will give you even more money.

I'm all over it. They didn't supply a media unit. I had to find one in store the day after release. I've since tested it extensively.

Firstly, the media reviews missed so much information I'm pretty peeved after having spent money on one only to have to find out all the finer points myself. It's the first radar to use 77GHz, that's a big change from the standard 24GHz all other radars currently use. NO review tested the extraordinary detection distance claims. No mention of the flashing pattern not changing on a detection. No mention the post mount was shitty on aero posts. No mention of the ANT+ Radar spec limitation of 196m maximum distance reporting that would/could possibly screw with head units.

All that aside, I set out to verify their claims of 240m detection distance. They'd hung their hat on this in their promo videos, every media review was parroting the same specs. HUGE if true. I couldn't. Not with an Edge and ConnectIQ app that shows vehicle distance. Putting that aside, visually I couldn't see it pick up cars any earlier than 140-150m with a rough measurement, it was definitely not 240m. After obsessing about what I screwed up with my testing overnight, the next morning I was out testing the unit side-by-side with the Bryton Gardia R300L then the Garmin Varia RTL515. I observed NO difference in the detection times/distances in what I would consider near perfect conditions. That was all captured in full 4k... along with someone flipping me off and mouthing something at me for standing on the roadside looking like a speed trap. Nice.

Road Test:


Side-by-Side Test:


I had to put in WAY too much work in an attempt to have this device prove itself. It never did. 240m is a BIG claim. BIG.

I've since had two calls with Trek (Friday and Monday). Kudos to them for answering my queries and wanting to discuss my testing protocol/conditions. They're confident in the measurements/testing they'd done, which is great. I can't replicate their results with the unit I purchased.

I'll give it a little more time.. but not much. Stay tuned. I'm in the states for a week and have the unit with me. I might pick up another while I'm here and do more testing before putting up a review in full.

I love their math example of the benefit of their extended detection range. Who rides 25kph on a road with 100kph car traffic?

I use the radar without a light and the bontrager flare.rt. No camera but the best of both imo. My u it is 4yrs old I guess and still lasts 5hrs plus.

After having my second Flare RT die in wet conditions – which was a warranty replacement of my first Flare RT that also died in wet conditions – I would never touch them again. Since this can leave you in the dark and rain without a rear light, IMHO it is a major problem with this product.

thanks for the review. personally, if i have 140yd or thereabouts that's fine for me. if somebody actually comes out with a radar that'll alert me if the car is going to run up the rear of me, that i'd be interested in. i recognize that would probably require some granularity that doesn't exist in the tech.

Do you have one of these, Dan?

I used to think the same as you - this this isn’t “good enough”. But my varia is far and away my favorite cycling purchase I’ve ever made. I don’t like riding without it

For bikes that don't have an easy way to attached a rear radar - has anyone successfully attached to a jersey pocket for a ride?

So, while these radar-driven behaviors do not eliminate run-up-the-rear risk, they greatly reduce it.

Radar is absolutely a great tool. I use it all the time. Just don't think it does anything to reduce the naked risk of being run up from behind.

I could not ride outside without it now...

I did a long ride with a friend Saturday, and my Garmin was dead. So, I had no radar. Fortunately he did. I felt a little exposed not knowing whether a car was approaching except by trying to discern from his Garmin's beeping. I found I like knowing what is going on behind me without having to look.

a mount that would extend from the back of the saddle makes sense to me.

a mount that would extend from the back of the saddle makes sense to me.
that amazon one on your link looks to extend back from the saddle a bit (leaving some room for that seat bag).

For bikes that don't have an easy way to attached a rear radar - has anyone successfully attached to a jersey pocket for a ride?