How to Choose Bike Lights

Stay aware of approaching vehicles with this Garmin radar taillight. With precise radar tracking technology, it detects vehicle size and threat level. Pair it with a compatible device to get alerts.
Imported.
View the Garmin Varia Product LineView all Garmin Rear Bike Lights| Best Use | Cycling |
|---|---|
| Bulb Type | LED |
| Number of Bulbs | 1 |
| Max Light Output (Lumens) | 100 lumens |
| Taillight Mounting | Seat |
| Battery Mount | Integrated |
| Rechargeability | Rechargeable |
| Charge Time | 3 hours |
| Batteries | Internal lithium-ion cell |
| Integrated Battery | Yes |
| Battery Life on High | 10 hours |
| Battery Life on Low | Radar only (no light): 30 hours |
| Battery Life Flashing | Peloton: 15 hours; night flash: 10 hours; day flash: 24 hours |
| Weight | 3.2 ounces |
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After having used the RTL510 for several years, for me, the 820 offers a few significant improvements. The biggest, and only downside of the 510 (and the 515 supposedly had the same issue), is that you can very often get a false negative when a car catches up to you, and then paces you at your speed. By that I mean that the car will show up on your head unit when it is going faster than you, and then disappear when it slows to match your speed. Knowing this downside, when a car catches up to you and then drops off, you can't tell whether the car turned off the road, or is still there. With the 820, it somehow knows that the car is still there, matching your speed so the car doesn't disappear off your screen. This is a huge benefit, because now when the car disappears off the screen, you know it turned off the road. some other improvements are: much longer battery life; the ability to see which lane a car is in behind you; and it gives an indication of the relative size of the vehicle(s) behind you.
I’ve been buying Garmin products for years. This one is a disappointment. The light isn’t bright enough, and the unit is far too big. And pretty expensive. If you’re small like me, and don’t have a 12” exposed seat post, this device will not fit.
Picks up cyclist as cars quite often, very annoying to use in a group setting. Does pickup cars as well.




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