Garmin Edge 840 | 2024 Review & Testing

I’ve owned a number of cycling computers going back to an old Ciclosport and some early Garmin Edge models. For the last 10 years I’ve been using various models of the wrist-based Garmin Forerunner to support my triathlon habit. This season I finally realized that given how many hours I spend in the saddle I really should be enjoying a larger screen. Plus, while my Garmin Forerunner 920XT can snap off my wrist and onto my bike, my more recent Garmin Forerunner 955 cannot. After briefly entertaining the idea of a Hammer Karoo 2 (but knowing the new model was right around the corner) I quickly settled on the Garmin Edge 840. I think it hits the sweet spot for price, feature set, and size.

Unboxing and Setup

Because I already own an assortment of chest straps, and with cadence built into my existing SRAM Rival 1 AXS Dub power meter, I chose the device-only option of the Garmin Edge 840 for $449. It comes standard with a usb-c cable and an assortment of mounts. I poached the ENVE road stem computer mount from my roadie and threw it on my Trek Checkpoint SL7, so I’ll leave everything except the unit itself in the box for now.

It’s been years since I set up a new bike computer, so I wasn’t ready for how easy it would be. 

I already have the Garmin Connect app on my iPhone, so once I scanned the QR code it grabbed my profile and preloaded everything onto my new Garmin Edge 840. It even asked whether I’d like to add all of the sensors that are connected to my other Garmin devices. I was stunned by how quick and easy it was to have the device ready to use. Garmin then asks you to choose some activity types to add.

You can adjust the data screens on the device with seemingly limitless options, and the touchscreen is pretty darn nice. What’s even nicer? You can adjust the screens on your Garmin Edge 840 via the Garmin Connect app, which makes it quick and easy. Just make sure the Edge is turned on and connected to your phone.

First Impressions of the Garmin Edge 840

While I was going through the setup I was immediately impressed with the display’s colors and the quality of the touch experience. The other thing that stuck out is the screen’s real estate. Both the Garmin Forerunner XT and the Garmin Forerunner 955 have impressive features for multisport units, but adding more than a couple data fields to their screens results in fonts so small that you end up scrolling from one screen to another, which is a pain during a workout. With the Garmin Edge 840 I can easily have 6 data fields on a single screen. It’s a game-changer.

With setup complete I snapped the unit onto the mount on my bike to assess fit and to see how it looks (obviously). I’m glad I didn’t go with anything bigger. The Edge 840 looks great on my cockpit and fits nicely beside my Bontrager Ion 200 RT, after readjusting the light. Anything bigger would require a different mount and would feel pretty clunky to me.

Setting up a route for navigation on the Garmin Edge 840

I wanted to load a route for my Saturday group ride so I could send out a livetrack link and test data fields such as estimated arrival time. Back at the kitchen counter I located the course on Ride With GPS, which has a prominent “Send To Device” button. If you link your Garmin account, Ride With GPS will make the course available in both the web and app versions of Garmin Connect. From Garmin Connect, you can then choose to send the course to the Edge 840. The next time the Edge syncs with your phone it will grab the route. If you are as impatient as I am you can click the sync button in the mobile app to have the course immediately available. You can also use previous activities as a route, as well as grab them from popular platforms like Strava. With the route available on the unit I was ready to ride.

Riding with the Garmin Edge 840

To put the Garmin Edge 840 through its paces I decided to jump in a group ride that was sure to test my limits even more than the Garmin’s. On tap was 70 miles that encompasses much of the southern portion of SBT GRVL. 

A quick mention of LiveTrack for those who haven’t used it. LiveTrack let’s you send out a link, and provided you are riding with your phone, it allows friends and family to follow your progress. It works even better if you are using a loaded route with the activity because LiveTrack will estimate when you finish. Super handy for those of us balancing family responsibilities.

I chose my gravel profile to start a new activity on the Edge 840, and from the navigation menu on the device I chose my saved route. With that, I was riding. The turn-by-turn instructions are clear and very impressive, though if you know your route well you’ll likely find them distracting. On my way out to the gravel I found myself swiping left to dismiss the map and get back to my ride data. My other suggestion is to turn off tones in the Edge 840’s system settings. They are very helpful when you are riding somewhere new, but I was on my home turf. Finding and using routes when you are riding in a new town is powerful. It’s also great for racing.

As I mentioned, the screen size and brightness of the Garmin Edge 840 displays your stats well, even under bright sun. It may be the angle of my mount, but there were times when the sun reflected off the Edge’s screen and right under my Oakley Sutros. Annoying. Back on the plus side, swiping between screens was a breeze – even with gloves on.

ClimbPro on Garmin Edge devices

ClimbPro came to Garmin devices a couple generations back. With the Edge 840 it now works without a route loaded, a requirement of previous iterations (as with my Forerunner 955). I was using navigation, but it sure will be nice on future rides to have ClimbPro pop up regardless. When you approach a climb, ClimbPro automatically  shows a gradient chart of the climb along with some customizable data fields. I chose Power and Grade, only to learn that it already shows the grade along with your progress as you climb. One thing I don’t quite understand is why it shows the total elevation gain and remaining elevation of the entire route, and not just the current climb. 

Results

The Garmin Edge 840 does an impressive job estimating your remaining time. Even with an unexpected headwind it accurately predicted my arrival almost two hours out. Upon completing a ride, the Edge 840 shows not only the raw stats, but also a performance assessment. 

The ride is quickly available on the unit and by the time I take off my shoes and helmet it syncs to Garmin Connect via wifi. 

Conclusion

While the Garmin Edge 840 doesn't have as much screen real estate as options like the Hammerhead Karoo, the screen quality and responsiveness is superb. 

Saved routes and ClimbPro are game changers if you are riding on unfamiliar terrain. I used the Garmin Edge 840 at the 2024 Grasshopper Ukiah-Mendo Gravel Epic. I flew out from Colorado 48 hours in advance and arrived at the start town the afternoon before race day. With no chance to pre-ride I came in completely blind to the course's 75 miles and 8,400' of climbing. This is where this computer really shines. At every point during the race I could see exactly what was in front of me. This was absolutely crucial for a steep section around mile 45 because it wasn't obvious when looking at the event website just how tough the middle of the course was. Seriously, the Garmin Edge 840 saved my butt because it showed me I needed to gear down to avoid blowing up.

Where the Garmin Edge 840 is strong

• Ease of setup - Initial setup is a breeze and, importantly, you can configure data screens from your phone. This is one feature that other bike computers like the Hammerhead Karoo lack.
• Swipe and click - I find the Garmin Edge 840's touchscreen very responsive, even with gloves on. That said, you can always also use the tactile buttons on the sides of the device for all operations.
• ClimbPro - The climb profiles are very accurate, even when I don't have a route loaded. 
• Routes - Easily send routes from Garmin Connect and Strava straight to your device.

Where there is room for the Garmin Edge 840 to improve

• Screen layout - The screen is nice, but I wish it had some default metrics always showing. On the Hammerhead Karoo, the time of day and total ride time always appear at the top of the screen, saving your configurable fields for additional data. On the Garmin Edge 840 I have to use two data fields for these. Also, the size of the bezel on this unit feels outdated.
• ClimbPro Layout - While ClimbPro is pretty amazing, there are two areas where it falls short. First, you can only configure two customizable data fields, so you lose metrics when on a climb. Second, it can get annoying when ClimbPro pops up on climbs you know well. I find that I have to constantly swipe back numerous screens to get back to my main data screen. You can turn this off in the settings, but then you have to remember to turn it on when you are on a new course. It would be nicer if you could quickly swipe down to dismiss ClimbPro and return directly to your data fields.