Trek’s Ion and Flare lights have been a popular choice with road cyclists thanks to their compact form factor and focused single LEDs. While they aren’t bright enough to light up the road they are perfect for daytime riding and are easy to mount on city or road bikes. After being on the market for years, Trek has finally updated the lights with the big highlight being fast USB-C charging and a battery gauge. Retail price on the individual lights is $44.99 while the combination lightset comes at a slightly discounted $84.99. The Ion R has 100 lumen output while the Flare R has 35 lumen output. Both lights use Blendr compatible mounts along transparent side windows for side visibility.
The Trek Ion 100 R and Flare R are compact daytime visible lights that have been finally updated with USB-C charging and sleeker designs.
| Rating | 9.6 / 10 |
| Retail Price | $84.99 ($44.99 individually) |
| Measured Weight (in g) | 25 (each light) |
| Likes | + Compact form factor that is is easy to mount with Blendr compatibility + Finally gets USB-C ports with longer runtime and faster charging + Daytime bright with eye catching flash mode |
| Dislikes | – Top mounted battery gauge on headlight can be distracting – Red LEDs for taillight battery gauge is a bit confusing |
| Where to Buy (US) | Trek |
UNBOXING
The Trek Ion 100 R and Flare R lightset comes in a sleek white cardboard box with black Trek branding printed on it. A large center cutout exposes the headlight and taillight allowing you to interact with the lights inside the packaging. Once you open the box you’ll find:
- Ion 100 R headlight
- Flare R taillight
- 0° offset handlebar mount
- 16° offset seatpost mount
- USB-C charging cable
- User manual
As with other Trek products, the packaging is eco-friendly with no plastic bags or even a plastic window for the outside of the box. Instead there is a clever use of cardboard with cutouts in the backing to hold the lights securely in place.
MOUNTING
Both the Ion 100 R headlight and Flare R taillight use Trek’s slide-on tab design that is shared across products. It’s Blendr compatible which means you can use the included seatpost and handlebar mounts or directly mount them on a saddle or off handlebars for a cleaner installation. The included rubber straps feel thick and sturdy with multiple attachment points to accommodate different diameters. To account for the seat post angle, the taillight mount has a built-in 16° offset. Interestingly the lights can also be rotated around the mounts a full 360 degrees which gives you more flexibility on the mounting location. While we would have preferred a miniature quarter turn Garmin mount, Trek’s tab mounts have a lot of available Blendr accessories and feel very secure.
FIT & FINISH
Visually, the Ion and Flare R lights have the same iconic cube shape design as the original lights. Both lights are nearly identical in shape but Trek has added a red colored lens to the taillight to make it easy to differentiate between the two lights without having to turn them on. The lens itself also has a square shape instead of being round like the previous model and feature a dimpled outer surface to disperse the light and a clear inner section that reveals the single LED. Beneath the lens you also have Trek engraved which is the only visible logo or branding on the lights. The other difference is that both lights now have a glare shield integrated into the body instead of a smooth shape of the previous version. It’s a slight extension with a longer extension on the top which ensures you don’t get blinded by the light if you are out of the saddle.
Trek has also upgraded the indicator light from a single colored LED to a four bar LED light bar that is similar to the Trek CarBack radar. It’s a nice upgrade that avoids the confusion of remembering what colors map to as each bar is 25% battery. Once you are below 5% the single LED flashes to remind you that the battery is at a critical level. On the sides of the body you have transparent lens cutouts for side visibility which is a feature a lot of bike light companies forget to incorporate. There is a USB-C port underneath a slim cover which reduces the charging time and is a long overdue update from the previous micro USB.
Operating these lights is as straightforward as it gets with a single top power button. Holding the button for 1 second turns the lights on and off while a quick press cycles through the available modes. The lights have built-in memory so they always turn back on in the same mode they were in when they were shut off. Unlike the more expensive Ion and Flare RT models, the R lights do not have any Bluetooth connectivity, smart sensors or other features so they are more affordable and easier to operate.
LIGHT OUTPUT
Trek has programmed the headlight with three modes while the taillight has four output modes. Battery life is claimed to be improved across the board with up to 28% longer runtime and fast 2 hour charging thanks to the USB-C upgrade. The headlight modes are: high constant (100 lumen / 2 hr runtime), low constant (20 lumen / 5 hr) and daytime flash (100 lumen / 11 hr). Unless you are on a well it street, even the high constant mode isn’t enough to really light up the road but can be sufficient for urban commuting. Daytime flash mode on the headlight is bright and effective with an irregular flash pattern that draws your attention. Trek has done an excellent job with the lens design focusing the output to make the most of the 100 lumens and ensure visibility from long distances.
The taillight modes are: high constant (20 lumen / 5 hr), low constant (2 lumen / 21 hr), daytime flash (35 lumen / 10 hr), and night flash (2 lumen / 24 hr). The night flash is a low / high style flash that is less distracting for riders behind you but helps ensure you are visible. Again, the daytime flash is the star of the show with a long 10 hour runtime and surprisingly bright output despite being only 35 lumen. While it doesn’t match the brightness of the Magicshine Seemee 300 or even more extreme Ravemen TL500 with 3-5x brighter output, the lens design is highly focused with nice side windows for additional visibility. The updated design of the lights also mimics the Trek Commuter Pro RT and helps tie the lights together visually. Our only complaint was that the headlight’s green LED battery indicators were distracting as they were always visible while being mounted on our Blendr stem.
THE VERDICT
Overall, we found the Trek Ion 100 R and Flare R lightset to have welcome updates and upgrades. The Ion and Flare lights have always been a popular choice with cyclists thanks to the bright output and compact size, so it’s no surprise Trek has only made some modest updates. We’re happy to finally see USB-C charging on the lights with longer runtime and faster charging times to help make the light more competitive. The lights also look a bit more modern with a subtle glare shield and four bar LED indicator that takes the guessing out of battery runtimes. Both lights are still small and easy to mount with plenty of Blendr options for stealthy installations outside of the included rubber strap mounts. As far as negatives, we would have preferred to see the battery status indicators on the side of the light as they could be distracting while riding and green LEDs on the taillight indicator instead of red. That said, the updated Trek Ion 100 R and Flare R bring some modern updates to the longtime favorite lights.
Disclaimer: The product for this review was provided by Trek. The views expressed on this website are solely those of the authors and are here to help people make an informed choice before a purchase. The authors or the blog itself does not get any monetary compensation from the product manufacturer or third-party websites/vendor links that are posted here.