Coospo TR70 Radar Rear Light Review

By Brandon Bilyeu

Hot!

• Price
• Accurate identification of objects approaching from behind
• Bright light with mode options
• Good battery life, USB-C charging
• Fits any seat post shape
• IP67 waterproof (dust + immersion)
   

Not!

• Ghost object detection in built up areas

Price: $112

Size: 96mm x 39mm x 23mm (3.8” x 1.5” x 0.9”)

Weight with mount: 85g

Connectivity: Bluetooth and ANT+

Charging: USB-C

Battery Life: up to 40 hours

How obtained: review sample from Coospo

Available: Coospo and Amazon

Website: Coospo TR70

RBR Sponsor: no

Tested: 20+ hours

Rear Radar at a Reasonable Price

In the last few years there has been a flood of manufacturers entering the rear radar game and Coospo is the latest entry.  Coospo’s offering, the TR70, is a compelling option with excellent radar performance at a price that undercuts the competition.  And the TR70 can often be found on sale for an even better value.

The TR70 combines a rear light with radar functionality.  The radar detects objects that meet two criteria: 1. the object is behind you, and 2. the object is moving faster than you are are (closing the gap).  When both criteria are met your bike computer or cell phone can alert you of the closing object.

Recently, RBR’s Stan Purdum answered a reader’s question about radar versus mirror and one of the main takeaways for me is that both radars and mirrors can’t protect you, but only offer information about what is behind.  With the TR70 radar connected to my cycling computer I hear a beep when there is a faster moving object (car, truck, motorcycle, bike, velociraptor) approaching me from behind.  I appreciate that I can get a warning about something approaching from behind without taking my eyes off the road ahead.  And once I hear the audible warning, I can decide what I want to do with that information.

In The Box

The TR70 comes neatly packed in a small cardboard box with the following components:

1. TR70 Radar
2. Round Seat Post Mount
3. Aero Seat Post Adapter
4. D-Shape Seat Post Adapter
5. USB-C Charge Cable
6. User Manual
7. Lanyard

After fully charging before the first use, installation on the bike is quick and easy.  Pick the correct adapter for your seat post type and strap on the mount where the TR70 can have an unobstructed view rearward.  The TR70 connects to the mount with a Garmin-style quarter turn interface that is quick and secure.  After many road and gravel miles I don’t have any concerns about losing the radar on rough roads, but you can use the lanyard as extra security for a mount failure.

Settings and Setup

The TR70 uses a single button for power on/off and cycling through seven light modes.  In addition to the seven light modes, the TR70 rear light also flashes brightly during object detection and under hard braking, warning those behind to your presence or slowing.  The TR70 has both rear and side lights for 220-degree visibility.  In the Coospo App, you can view the radar detection screen and adjust light and radar settings.  

For battery life testing, I ran in Low Brightness mode and shut off all the remaining modes in the App.  I hit 20 hours of usage, and the App still showed 38% battery life remaining, so the run times in the image below seem accurate.  For maximum battery life you can use Only Radar mode, which keeps the rear light off until an object is detected and then will it flash.  There is a small indicator light at the bottom of the TR70 that flashes slowly to let you know the radar is on, since in Only Radar mode the TR70 looks like it is off.

User Interface

Outside of the Coospo App, the TR70 sends a standardized data signal to your bike computer, but has no control over how that data is displayed.  Your bike computer processes the signal and displays what the bike computer manufacturer has implemented for radar support.  The TR70 is compatible with Coospo, Garmin, Wahoo, Bryton, and iGPSPORT computers and in general they display the data in a similar manner with user configurable options like audible alerts and visual settings.  

When nothing is detected, your computer screen remains normal, but upon detection there is an audible beep to get your attention, and a ‘road’ appears along the side of the computer screen showing the objects moving towards you.  The TR70 has a detection range of 140 meters (153 yards) so the ‘road’ from the bottom to the top of the screen represents this distance and thus you can get a feel for how close an object is and how fast it is approaching.

This is helpful information, but with a 40-degree radar sweep you can’t always know if the detected object is directly behind you and presents a risk.  You could be on a separated and protected cycling lane where an object detection could be a cyclist coming from behind or a car on the road that does not pose a risk.  So, you still need to evaluate the situation, but at least you know ahead of time that there is a situation.

Accuracy

In my testing, I was very careful to compare reality to what the TR70 was telling me, and I can confidently say that I never observed a failed object detection.  That is to say, the TR70 never missed an object, and I always received a warning.  There was never a case of a car flying by that I was not already aware of from the radar.  The core functionality of the TR70 worked flawlessly.

Ghost objects were a different story.  This is when you receive an object detection warning when there is no object present.  These fall into the annoying category, but not a safety issue.  On wide open country roads ghost objects were incredibly rare, but the deeper you ride into built-up areas the more they occur.  Buildings and infrastructure provide so many radar reflections that the software is momentarily tricked into seeing a closing object.  These warnings typically clear after about one second.

Bottom Line

The Coospo TR70 Radar provides great performance at a reasonable price.  It provides useful information without becoming a distraction itself.  Best for use on low traffic roads, less useful in high traffic areas where you don’t need a reminder that there are always cars behind.

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Brandon Bilyeu is an avid recreational roadie who lives in Regensburg, Germany. He’s a year-round bike commuter and is a mechanical design engineer by trade. Click to read Brandon’s full bio.