Bontrager Flare R Tail Light Review

By Sheri Rosenbaum

Visibility Even in Bright Sunlight

Doing everything we can to be visible on the road, day or night, has become vital for cyclists in this era of distracted drivers. For more than two years, I have been using the Bontrager Flare R tail light whenever I ride any of my four bikes (road, fat tire and cross). Four months ago, I added the Bontrager ION 800 RT headlight to the mix for additional daytime safety (click the link to read my review). I definitely feel safer using a daytime running light in front and a highly visible tail light in back.

It’s amazing that the first year I had my Flare R riders would stop and ask what kind of light I was using. It is so visible in bright sunlight that I can be seen from 2km away. Now that the light has been on the market for a while and being used by many more riders, I get asked less frequently. But I still have inquiries from time to time, not only from riders but drivers, too.

Since I bought the Flare R a couple years ago, Bontrager has introduced the Flare RT. They are basically the same tail light with the exception that, with the RT version, you can use the optional Transmitr for wireless on/off, battery status, turn signals and mode selection, or pair with select Garmins.

Settings for Different Conditions, Day or Night

The Flare R/RT uses balanced optics for 270-degree visibility both near and far, which increases safety. There are different visibility settings that let you dial in exactly what the conditions warrant. The LED indicator light on the top of the unit glows green for a full charge and changes to red when the battery needs to be recharged. The battery-save mode goes into effect at 5% life, which helps to you get to your destination safely.

Setting & Battery Life

• 65 Lumens flash (day mode) — 5.75 hours
• 35 Lumens (day mode) — 10 hours
• 25 Lumens steady (day mode) — 4.5 hours
• 65 Lumens flash (night mode) — 23 hours
• 5 Lumens steady (night mode) — 21 hours

I have yet to drain the battery on a ride, but have gotten in the habit of recharging it after every two or three rides depending on the ride length.

Wireless Control via Transmitr ANT+ or Garmin

As noted in my Bontrager 800 ION RT headlight review, you can control the Flare RT (not Flare R) wirelessly using an optional Transmitr ANT+ remote (which costs an additional $49.99; see photo) or by using select Garmin devices. The remote or Garmin device can turn the light on/off, select the mode, view real time light battery status, and more. One interesting use of the Transmitr is to pair with multiple Flare RT rear lights for turn-signal configuration. The remote uses a common CR 2032 battery. Since it is not in constant use, the battery life is fairly long.

Pair With Your Garmin Unit

As with the Bontrager ION 800 RT, the Flare RT (not Flare R) can be paired with your Garmin Edge 100, 820 or 520. Read more about syncing in my earlier review.

If you already own a Garmin Edge 1000, 820 or 520, you don’t need to buy the Transmitr. The Flare RT (not Flare R) is easily paired for wireless control and battery status. You can also use older models like the 510 or 810 with a plug-in update.

Back when I was testing the ION 800 T, neither Garmin nor Bontrager had a manual on syncing or using the light with the Garmin head unit, so I winged it. It turned out to be quite easy and fast to sync the the Flare RT and 800 T.

Once the light was synced, the Garmin can be set to manual or auto mode to turn on/off the light. In auto mode, if you are riding in daylight the Garmin automatically turns the light on, and sets it to daylight flashing. This functionality is feeding off the Garmin sensor that automatically turns on the night backlight feature.

Not having to fuss with your head or tail lights, and having them adapt automatically to changing conditions, is very useful. It’s just set it and forget it. I also like that you don’t have to guess how much battery life you have left; it’s all there on the display.

Easy Transfer from One Bike to Another

As I mentioned earlier, I use the Flare R on all my bikes. My unit is from when the light was first introduced and came with a clip that attaches easily to the saddle bag loop. The current model of the R and RT comes with a silicon strap, and the clip can be purchased separately. The Quick Connect bracket of the R version easily attaches to the seatpost and has a 16-degree offset to compensate for the angle.

The Bottom Line

I’ve been using the Bontrager Flash R for over 2 years now. With its great visibility day or night, I definitely feel safer since cars see me earlier. I’ve had zero problems with the light even after using in all types of weather conditions. Many riders have stopped me and asked what type of light I’m using because they see how bright it is in daylight. Combine the brightness with the long-lasting battery life and this tail light is a winner in my book.

August 2017

Sheri Rosenbaum

Sheri Rosenbaum regularly contributes articles and reviews products for RBR. She’s an avid recreational roadie who lives in the Chicago area and a major advocate for women's cycling, serving on the board of directors and volunteering with the Dare2tri Paratriathlon Club. Click to read Sheri's full bio or visit her web site sunflowersandpedals.com.