Review: Garmin Edge 840 Solar

On a recent bike-packing trip in southern Utah with my partner, Brian, and another couple, I found myself bemused by the guys’ attachment to their GPS cycling computers. At the end of each day, they pored over stats as if they had just competed in a stage of the Tour de France. I had a cycling computer too, and would admittedly have been lost without its wayfinding wizardry. But I still find myself in an internal debate over whether all the data they spit out diminishes the joy of just riding my bike.

I obviously haven’t resolved that question, since I jumped at my editor’s offer to test the new Garmin Edge 840 Solar. It’s almost exactly like the Edge 1040 Solar that debuted last year, but it's about half the size, which means it also has half the gigabytes—32—of internal memory and a little less than half the solar-charging power. The more petite 840 Solar, however, is still a highly competent device. The Power Glass solar charging lens extends battery life up to 32 hours (with Battery Saver mode off) and up to 60 hours (with Battery Saver mode on). It has multiband GNSS that makes the wayfinding even more accurate. And it offers a handful of new features like ClimbPro, which profiles the gradient of every climb on every route you ride that’s longer than 500 meters and steeper than a 3 percent grade—no preloaded course required.

Photograph: Garmin

The 840 Solar also offers a handful of new training features that, when used in conjunction with a power meter and heart-rate monitor, is like having a coach on your handlebars. For existing Garmin users, these are even more powerful because they can tap into your existing training data stored in the Garmin Connect app (which is required to operate the device).

Say you have an upcoming race. The Targeted Adaptive Coaching feature allows you to download the date and other details of the event into Garmin Connect, and the computer will spit out customized suggested workouts and training prompts that you can adapt to your current training load and recovery. It even counts down to race day, giving you the weather report in Kansas or California or wherever the race may be. The more historical data you’ve previously downloaded, the more accurate the workouts will be.

Other features include Real-Time Stamina, which gauges your output then spits out the remaining time and mileage left before you bonk, allowing you to manage your ambition more realistically. Cycling Ability matches your strengths as a cyclist with the demands of the course you’re riding so that you can maximize the day’s effort.

Photograph: Garmin

Since the 1040 debuted last year, Garmin has updated several wayfinding features in the Edge 840 Solar to make them more specific to cycling. Its maps are now ride-type specific, highlighting popular roads and trails and searchable cycling-specific points of interest like bike shops. Also, say you want to purposely veer off course to explore a beach or an espresso shop. You can now pause your course route so that the diversion isn’t calculated into the official route. When you’re ready to jump back on course, the device will steer you back to where you can reengage. Another key feature that Garmin keeps refining is Incident Detection, which automatically sends a message with your location to your emergency contacts after the Edge’s sensors detect that you’ve had a crash.

As for how to access these shiny new features, Garmin added a lot of buttons to the Edge 840 Solar. It has seven in total–that’s four more than the longtime Garmin standard of three. It looks intimidating until you realize you now have the advantage of navigating via touchscreen controls in nice weather or using the buttons when you’re riding in rain or while wearing thick gloves, which is a nice addition, especially for cyclists who often ride in the cold.

Photograph: Garmin

What you see on the screen was updated last year on the 1040 when Garmin revamped its user interface to make navigating the device faster and more intuitive. Its homepage can be customized to include shortcuts to a long list of features like Training, Navigation, History, Notifications, Weather, Sunset, Fitness Age, and Recovery Time. Or it can include just one of those. Scroll down to access a category, press on it, and a whole universe of data is at your fingertips. Sunrise/Sunset, for example, offers the time of sunrise and sunset for the next two weeks, which is helpful if you live in a climate where daylight hours vary greatly as seasons change. Training opens to all the aforementioned new training features. Some of the tools, like Fitness Age, require preloading your VO₂ max, resting heart rate, and body fat percentage in the Garmin Connect app on your phone.

Photograph: Garmin

So how does this all translate while on a ride? As Garmin is quick to point out, to optimize the solar charging, the device needs to be mounted flat on your handlebars to catch maximal sun rays, not tilted at an angle. April clouds that lasted for weeks in northern Minnesota did not bode well for solar testing. On more than one midday, two-hour lunch ride, I had no noticeable power gain, because it takes the device about 1.5 hours to gain a measurable 1 percent in sunny conditions. That level of gain translates to 21 additional minutes of ride time in demanding use or 42 minutes in Battery Saver mode. On the one full-sun day I had time for a three-hour ride, I did get a nice 40-plus-minute bump in battery life. So, the system works nicely when the sun’s out, but don’t toss out the charging cord—especially if you live in a place that's frequently cloudy.

For data geeks or athletes in serious training mode, ClimbPro is a handy tool. Climbing profiles, pages that show real-time data such as gradient while you're climbing the hill, aren’t unique to Garmin—Hammerhead pioneered it in its Karoo 2 cycling computer a few years ago. I am not a data geek or an athlete in serious training mode, but I do like Garmin’s color-coding that allows you to easily see the climb’s varying gradient. Plus I get a shot of dopamine when I hear the party bells that chime when I’ve crested a climb. But I also like leaving a little bit of the day’s adventure (and struggle) to the imagination, especially when the climb is a never-ending grind. The beauty, however, is that Garmin gives you the option to toggle off ClimbPro, so I can use it when I want or ignore it.

In fact, that sums up the beauty of the Edge 840 Solar. It offers everything you need in one impressively compact device, whether training for a 350-mile ultra-race, bike-packing off the grid for five days, or just trying to maintain a base fitness level as you navigate the complexities of life. And if the data gets too overwhelming, you can customize it to display only what you need and nothing more.