The Portland Design Works’s Gravity Plus USB taillight is a classic dual LED taillight that is one of the brand’s brightest taillights. Even though the taillight has been part of PDW’s lineup for a number of years, the taillight has modern features that help it stay competitive. Retail price for the taillight is an affordable $40 which includes a USB-C charging interface. The taillight is rated for 100 lumen output along with an integrated brake sensor. PDW has also designed the Gravity Plus to be mounted horizontally or vertically with a simple clip-on style mount along for seatposts or backpacks.
The Portland Design Works Gravity Plus is a simple yet bright 100 lumen taillight with a built-in brake sensor.
| Retail Price | $40 |
| Rating | 8.0 / 10 |
| Measured Weight (g) | 46 (taillight w/ clip), 23 (seatpost mount) |
| Likes | + Bright output with 100 lumen output + Dual direction mounting with simple clip design + Simple two mode options with day and night mode |
| Dislikes | – Dated appearance with large red lens and dual LEDs – No multi-level battery status indicator to check battery with – Brake sensing function can not be disabled |
| Where to Buy (US) | Portland Design Works |
UNBOXING
The Portland Design Works Gravity Plus taillight comes in a compact cardboard box with white, blue and red stripes reminiscent of BMW M graphics. The box has a cutout that lets you interact with the taillight while it is still in the box. Inside the box you’ll find:
- Gravity Plus taillight w/ body clip installed
- Seatpost mount
- USB-C charging cable
- Instruction manual
MOUNTING
PDW includes two mounts with the taillight, a backpack clip and seatpost mount. Both mounts have a simple tab design with a square backing that slides into the taillight. It’s a simple design that allows either mount to be attached vertically or horizontally for different bike configurations. The backpack clip is a simple plastic clip with a raised tab to help hold it in place and clips into the body of the taillight as well as the seatpost mount. It’s a great way to attach the taillight to a saddlebag, backpack or a jersey pocket quickly and easily. The backpack clip slides into the seatpost mount with a simple tab design which makes it easy to swap between different mount locations.
The seatpost mount is what Portland Design Works calls their Stayputnik mount and it has a very thick and durable plastic and rubber construction. One unique feature of the seatpost mount is that it has an adjustable angle with three positions to ensure the taillight is oriented correctly regardless of the bike geometry. You have to push with quite a bit of force to adjust the angle though which ensures the taillight doesn’t rattle or move on the bike. Note, the angle of the taillight is particularly important with the Gravity Plus taillight as it is used to calibrate the brake sensor.
FIT & FINISH
Visually, the Portland Design Works taillight has a classic taillight design with extended red plastic lens and exposed circuit board beneath it. The design reminds us of Planet Bike Superflash lights with its larger size and traditional dual LEDs. There is a main LED on top with a convex lens to help distribute the light along with a second LED below it. PDW has also added a basic low battery status indicator with a green LED which means you’ll need to preemptive charge the taillight as there is no clear status indicator. The taillight has basic branding with an upward arrow and plus indicator above the PDW logo.
To control the light you have a black rubber power button in the center of the taillight which you simply hold to turn the light on and off. Where most lights have complicated mode options, the Gravity Plus USB only has two modes. There is also an accelerometer integrated into the taillight to detect braking and automatically switch to a bright 100 lumen constant mode for two seconds. There is no option to turn the feature off though, which means runtimes will vary depending on how often the brake sensor is triggered. Note, PDW also recommends only turning on the taillight when it is on the bike as the brake sensor calibration is done at each power on for one second to ensure the sensor works properly in horizontal or vertical positions.
LIGHT OUTPUT
The Gravity Plus is pre-programmed with only two modes with no need for an app or any configuration options. It’s one of the simplest bike lights we’ve reviewed and is a nice change of pace compared to complicated smart taillights. The two modes are: daytime flash and a constant mode. In the constant mode only the bottom LED is illuminated, while the flash mode and the brake mode activates both LEDs. PDW rates the constant mode at 20 lumens with 12 hour runtime white the flash mode is 80 lumen and 30 hour runtime. It’s a very simple lens design which means you primarily get a bright single point from the individual LEDs. The upper LED is more diffuse with the curved outer lens and helps with long distance visibility.
The extended red taillight housing looks and feels a bit dated, particularly compared to lights like the Magicshine Seemee 300 or the Trek Flare R, but it is effective. With the light on, the lens is illuminated which provides excellent side visibility. The daytime flash is bright enough for day use with an irregular flash that gets cars attention. The brake sensor on the taillight automatically switches the taillight to a 100 lumen constant mode that turns on both of the LEDs. It’s a big visual difference between both the constant and flash mode so it catches your eye when the mode changes. We found the sensor calibration to be on the sensitive side, as it tends to trigger even with minor speed changes and not just full stops. Personally, we would have liked to see an option to disable the brake sensor as it results in reduced runtime.
THE VERDICT
Overall, we found the Portland Design Works Gravity Plus to be a simple and effective bike taillight. PDW has used a simple two LED design with only two modes for daytime and nighttime use. While the Gravity Plus isn’t the most modern in appearance, the taillight has modern USB-C and a well calibrated brake sensor. We were impressed with the clever dual direction mounting that incorporates the body clip into the seat post mount and provides flexibility. Although having only two modes is unusual; it is more than enough for most cyclists and a welcome change from taillights with an excessive number of modes. The downsides of the taillight is the lack of a multi-level battery status indicator and that the brake sensing mode can not be disabled. That said, the Portland Design Works Gravity Plus is a bright and simple bike taillight.
Disclaimer: The product for this review was provided by Portland Design Works. 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.