Garmin Varia eRTL616 (bike radar powered by your electric bike): our review

A Sunday route can leave the village behind and put you beside faster traffic before your legs have properly warmed up. The Varia eRTL616 offers a claimed detection range of 140 m, around the middle of the cycling radar market. Favourable conditions allow that maximum reach; it is not a fixed boundary at which every approaching car will appear. Think of it as extra information for the road ahead of your next decision.

Its detection angle of 40 ° represents a typical detection field. Awareness still involves looking behind. Before moving out around a parked van, the glance over your shoulder remains part of the job. We place this model well overall because its electric bike power supply gives regular riders a practical reason to choose it: rear traffic awareness without another accessory to charge separately.

The defining detail is its power supply: the electric bike powers the radar. For the commute home as daylight fades, that removes a separate radar battery from your charging routine. Your electric bike still needs its own charging discipline, of course. The kitchen socket has enough responsibilities already.

This model mounts on the luggage rack, so the purchase decision starts at the back of the bike. Confirm the rack fitting and electrical connection with the retailer before ordering; a rack being present does not establish that the installation will work.

At 50 g, it is a light unit whose weight should be easy to forget beneath the saddle. The specified mounting position remains the rack, though, leaving the seatpost out of the fitting equation. That is a useful distinction when a saddle bag already occupies the space behind you.

The stated lighting mode is steady. For a cyclist leaving work under a darkening sky, that makes the choice straightforward, without a collection of flashing patterns to consider. The specified output is 5 lm, a modest light intended to make you visible rather than attract attention from far away. That limited distant conspicuity is our main reservation. The rear light is there to be seen, rather than to illuminate your route.

A steady mode will suit riders who simply want the same lighting arrangement each time. Prefer to choose a flashing pattern for different journeys? This radar light gives you no such choice. We like the simplicity, but your usual lighting habits should decide how appealing that really is.

Bluetooth and ANT+ are the specified connections. The Varia eRTL616 has verified compatibility with a bike computer from Garmin. Check support for your particular bike computer before buying, because those connection names do not establish universal compatibility.

On a club ride, with riders cycling abreast and conversation competing for your attention, rear traffic information has a clear purpose. The receiver belongs in the buying decision. You want the bike computer on your bars to support the radar you choose, rather than finding yourself with an accessory that cannot join your existing arrangement. A familiar screen is useful only when the pairing is supported.

With its longer detection range of 160 m, the Sigma RECO 81 LINK is better suited to fast roads. That extra reach makes the Sigma RECO 81 LINK worth considering when approaching traffic on open roads is the central concern behind your purchase.

The Sigma RECO 81 LINK also has a higher detection angle of 60 °, giving it a broader detection field. The Sigma RECO 81 LINK is better rated overall, too.

The case for the eRTL616 is more specific: an electric bike, a suitable luggage rack and a preference for drawing power from the bike itself. Integration is its strongest argument. If your bike already comes indoors for charging after regular journeys, keeping the radar within that routine has a practical appeal. Choose it because that arrangement suits your bike and your habits.