Orny's Cycling Journal

In addition to the HUI-VUI, I’ve discovered another thing that happens every six years: I purchase a new GPS bike computer. In this case, we’re talking the Garmin Edge 840 Solar, which I picked up last month after it came out back in April. A new GPS head unit is a really big deal for someone who spends as much time in the saddle as I do.

Before diving into the new unit, let’s look at how far we’ve come. I first used a GPS to log bike rides waay back in 2000, using Garmin’s original yellow eTrex handheld, but the tech back then was so primitive that it didn’t have maps or routes or points of interest; just a blank monochrome 64 x 128 pixel LCD with a breadcrumb trail of where you had gone, and even that initially suffered from “Selective Availability”: an intentional inaccuracy imposed by the government on civilian GPS signals. Six years later I grabbed an eTrex Vista (my review), which had finally added color and some very rudimentary maps. In 2011 Garmin released the cycling-specific Edge 800, then 2017’s Edge 820 (my review), and this year’s Edge 840.

Along the way, I’ve watched these units evolve into incredibly useful and sophisticated navigational and analytical tools. Garmin updates their cycling products about every three years, so I’ve usually skipped a generation (e.g., the Edge 810 and Edge 830). So when I buy a new unit, there are some substantial improvements and compelling new features to check out.

And by that point, my old unit is usually pretty worn out. That was certainly true of my loyal old Edge 820. To begin with, its touch screen – a novelty at the time – was very sluggish, and the processor took forever to calculate routes or pan and zoom the map display. And the Micro USB connector was outdated technology from the start. After a few years the screen faded significantly, leaving a prominent grid of its LCD guts showing through its faint display. And its battery life – originally billed as lasting 15 hours – had shrunk to about 90 minutes. These were the shortcomings that I expected the new Edge 840 to fix.

With that, let’s look at the new beast. As always, I’ll divide this review into four sections: things I’m neutral about; features I don’t know much about because I didn’t test them; features I’m excited about; and the things that already disappoint me. With an executive summary at the end.

The Neutrals

My main display: speed, distance, with power and heart rate charts

One of the most noticeable changes is a revamped UI. It works fine. Its organization of functions isn’t 100% intuitive. And it’s still based on “activity profiles” rather than gear, which has always seemed a bit clunky to me.

The unit also supports phone-based configuration. I really don’t see a ton of value in that over configuring the unit on a computer or the device itself.

Potentially useful features include alerts for upcoming sharp turns and high-speed roads. But the high-speed road alerts arrive way too late to be actionable (e.g. navigating to avoid them). And the last thing you want when speeding around a sharp turn is having to read and dismiss an alert popping up on your head unit. They’re nice ideas, but not practical (at least not with the current implementation).

An unexpected surprise was that when following a route, the GPS can now have your phone verbally announce navigational cues as you approach them. “In fifty meters turn right on Mesa Drive.” Another cool idea, but they’re just not intelligible when your phone is stuffed into a jersey pocket on your back.

The unit can also walk you through a heart rate variability stress test. This isn’t for general health purposes, but for telling you how well or poorly you have recovered from your previous rides. That’s not something I need to wait around for three minutes for a device to tell me.

The Cycling Ability feature can tell you what your general cycling strengths and weaknesses are, as a very gross training aid. Garmin doesn’t add much value by telling me that I’m an endurance specialist.

Same with their measurement of heat acclimation. A simple percentage is way too simplistic to be of any actionable value.

Another hamstrung feature is showing the battery status for all your sensors (e.g. heart rate monitor, electronic shifters, power meter), where you really need more discrete battery levels than “okay” and “dead”.

There’s also a ton of features that I don’t really care much about, but you might. But to be honest I really don’t have any opinion about things like incident detection, structured training plans, mountain biking metrics, hydration alerts, an integrated bike alarm, lost device finder, etc.

The Unknowns

It might surprise you that I didn’t bother testing the unit’s integration with my indoor trainer. But the only useful function that provides would be the ability to simulate the gradients of riding a known real-world course, which isn’t as engaging as riding in the richer worlds on Zwift.

The Power Guide feature gives you a plan for specific power numbers to match when following a particular route. Just not something I’m likely to want.

Same story with the Event Training Plan feature. I hate structured training and already know how to build and taper for a major event. Not something I need, and not something I’d look to a head unit to provide.

There’s also the new and very promising Group Ride feature, which lets groups of riders share their route, in-ride messages, and live map with everyone’s location. This sounds like a really awesome feature if a critical number of rides and riders adopt it, although it’s limited to Garmin’s most recent units. It’s only in my “Unknowns” section because I haven’t had any opportunity to test it out.

The Positives

My customized boot screen

Solar power gain, showing 71 minutes gained over a 9-hour ride

ClimbPro displaying map, elevation profile, current grade and power

Real-Time Stamina, estimating 21% or 17km remaining before bonking

Let’s start with the basics: critical things my Edge 820 did that the 840 still does. I can still download my activity FIT data files to my laptop, as mentioned above. It still communicates with my Di2 electronic shifting and displays what gear combination I’m in. I can still capture screen shots, as you can see at right. I can still set the text that appears on the startup screen. And you can still charge it from a portable USB battery while using it. Good!

Then there’s things that aren’t new, but are features the Edge 840 has improved upon. Starting with the most important improvement: battery duration is now listed at 32 to 60 hours! The touch screen is so much more responsive that it’s actually usable now! Panning and zooming maps is reasonably quick! Calculating and re-calculating routes takes a second or two instead of five to ten minutes! Adding the GNSS GPS system improves GPS accuracy in cities and other challenging areas! And while my old unit would show alerts when calls or text messages came in, the 840 also shows email and all other phone notifications! Very nice!

The passive solar receiver adds around 8 to 10 minutes of extra power per hour in Texas sun, which might not be a huge deal for folks in cloudier locales, and there’s a data page showing the unit’s solar efficiency. Even I debated buying the non-solar model when I learned that the special glass makes the solar screen a little less bright, but it seems fine, and way better than my old, faded Edge 820.

On the topic of charging, we’ve finally made the transition from a MicroUSB to a USB-C charging & data port!

One of the highlights of the new interface is a home screen with “Glances”, little UI widgets that summarize important information and link to the most frequently-used functions. For example, there’s a Weather Glance that shows current conditions and clicks through to a dedicated weather page. And the Navigation Glance will show and give you one-touch access to the route you most recently downloaded onto the unit.

But by far the most massive UI enhancement is the widespread addition of graphical data fields! Heart rate and power are no longer a single number, but also time-series charts that are color-coded for intensity. Solar power, route elevation and gradient, and several other data fields can be shown as color graphs that encapsulate a ton of information in a small screen factor. Very cool!

One special application of charts is the new Climb Pro page. When you begin a climb, a new page pops up to show your current power, how much longer the hill is, its current slope, and a chart that shows where you are on the climb, and color-coded undulations of how steep it gets over its entire duration. It’s a very handy little tool for managing your effort, especially on long or steep ascents.

And if you need to manage your effort over an entire long ride, the Real-Time Stamina page is a great new feature. It uses your history to estimate what percentage of your total endurance you’ve used up – and therefore how much you still have left in the tank – and what that translates to in terms of time or distance until you hit the wall and your performance plummets. This sounds like a gimmicky pseudo-feature, but on my recent 100-mile Livestrong ride, it accurately foretold that I’d run out of juice about 30 km before the finish.

I could have included this in my “enhanced features” above, but it deserves its own paragraph: enhanced text message functionality. On my old Edge 820, when replying to someone’s text message, I could only pick from a pre-set list of 8-10 basic canned responses. Now there’s about three times as many canned responses. And you can customize them in their mobile app. And you can add emoji. And the Holy Grail: you can even compose your own responses on the fly, using the on-device keyboard! Finally Garmin no longer artificially limits me to replying with “Yes”, “No”, or “Almost there”!

The Negatives

The most obvious and glaring negative is that the meager screen resolution (246 x 322 pixels) hasn’t increased. It’s not a huge issue, but a higher resolution display would improve my perception of the unit a great deal.

Garmin advertises a cool feature that will tell you your “fitness age” based on your measured physiology. Why is that a negative? Because you don’t get that piece of data unless you buy both a connected scale and wear a 24-hour fitness watch that’s paired to their central database. Garmin advertising this feature as available on their bike computer is completely misleading.

While I haven’t sussed out exactly which features require it, the bike computer will nag the user to not only install but keep Garmin’s smartphone app open and running in order to take advantage of certain online features (IIRC things like current weather, voice navigation, text messages, and phone notifications).

The only true malfunction I’ve experienced is that a distance alert I set failed to trigger on my recent 100-mile Livestrong ride. Unfortunately, I’ve only done one century ride, so this isn’t something I can test very often!

Finally, the unit often hangs whenever I disconnect it from a cable connection to my laptop. It’s recoverable, and most people probably don’t do this very often, but I download my activity data file after every ride, so it’s a big annoyance for me. Aside from the fact that the unit shouldn’t hang under normal operating conditions to begin with!

The Bottom Line

Six years ago, I was disappointed after buying Garmin’s Edge 820. After defining and owning the GPS bike computer market, they released an underwhelming product that was unimaginative, behind the times, and deeply flawed. As a result, more agile competitors like Wahoo and Hammerhead eagerly and justifiably took major chunks out of Garmin’s once-dominant market share.

Garmin seems to have learned their lesson. The Edge 840 has improved on several old features and introduced a raft of new functions. I’m genuinely excited by the improved UI and graphical data fields, the passive solar charging, ClimbPro, Real-Time Stamina, the enhanced SMS capabilities, and the potential of the Group Ride features. Assuming they figure out the missing distance alert, my only knock on it is the meager screen resolution; but that’s still markedly brighter and more responsive than my old, fading 820’s terrible display.

Am I happy with it? I’m delighted! While it’s not perfect, the Edge 840 is a tremendous improvement over my old 820, with far fewer built-in flaws.