Garmin Varia RearVue 820 review: The Varia has finally received an update, and it’s a huge one!

The Garmin Varia RearVue 820 marks a significant upgrade over its predecessor, the RTL515, establishing itself as Garmin’s flagship rear radar light for cyclists. Key improvements include a longer battery life, an expanded detection range of up to 175 metres with a 60-degree field of view, and the introduction of USB-C charging, replacing the outdated micro-USB port. The device also features enhanced lighting with a maximum output of 100 lumens and side LEDs that increase visibility to 220 degrees, making it one of the most comprehensive radar light systems currently available on the market. Design-wise, the RearVue 820 retains the same mounting system as previous Varia models, ensuring compatibility with existing mounts. However, the layout has been reversed, placing the radar panel at the top and the main light at the bottom of the unit. The light offers multiple modes, including Day Flash, Night Flash, Solid, and Peloton, with customisable settings accessible via the Varia app. Battery life varies depending on the mode used, ranging from 10 hours in Solid mode to 30 hours when operating radar-only, though activating additional features such as the brake light can reduce endurance. Despite its advanced capabilities, the RearVue 820 comes with some drawbacks. The unit is now the most expensive standalone rear radar light on the market, and many of its advanced features are restricted to pairing with specific Garmin head units, limiting full functionality for users with other devices. Additionally, Bluetooth connectivity can be inconsistent, and battery consumption increases notably when multiple features are active. Nevertheless, when paired with compatible Garmin devices, the RearVue 820 offers a powerful tool for enhancing rider awareness and safety on the road. The radar system itself has been significantly enhanced, capable of detecting multiple vehicles simultaneously, assessing their speed and size, and providing colour-coded warnings to the rider. This multi-vehicle tracking and lateral position monitoring represent a leap forward in radar technology for cycling safety. Furthermore, the device can deliver audio alerts through headphones when connected to a phone, allowing riders to receive warnings without needing to glance at a display, a feature that could improve situational awareness in busy traffic conditions. Overall, the Garmin Varia RearVue 820 is a substantial step forward in rear radar light technology, combining improved hardware, extended battery life, and sophisticated detection features. While the premium price and some connectivity limitations may deter casual users, serious cyclists seeking enhanced safety and integration with Garmin’s ecosystem will find the RearVue 820 a compelling choice. Its release signals Garmin’s commitment to advancing cycling safety technology, and it sets a new benchmark for competitors in the radar light segment.