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Here, we’ll run through the key similarities and differences of the two models but also refer back a competitor’s model, the Wahoo Elemnt Bolt – a device similar in both size and capability.
Garmin Edge 520 vs 820: Design
It doesn’t take a hawk-eyed cyclist to notice that these two computers look almost identical. But there is one major way they differ, and that’s the fact the Edge 820 has a touch screen, whereas the 520 uses buttons.
This difference is significant when you consider the poor reviews the 820’s touchscreen was met with when it was first released. At Cycling Weekly, we found it to be lacking, and had complaints about its responsiveness as well as its poor performance in the rain. Although, with that said, we have found a year and a half’s worth of software updates have improved matters a little.
The other place the two differ is in the battery life. Both the 820 and the 520 have 15 hours in GPS training mode, but the 820 can have 24 hours in UltraTrac setting. This extends battery life by periodically turning off the GPS and gathering data using the accelerometer instead, potentially useful for those doing bigger touring adventures who don’t want to burn all their battery.
What about the Wahoo Bolt?
Whereas the Garmin Edge 820 and 520 look almost identical, the Wahoo Elemnt Bolt couldn’t look more different.
Its USP is that it’s the first cycling computer purposely designed to be aerodynamic and to this end both the computer and mount are a single unit, which Wahoo argues gives it a saving of 1.5 watts over the Garmin Edge 520.
As equally original is the fact that it uses a series of LEDs to help inform your ride. These can be programmed to flash depending on your speed, cadence or power output as well as to inform you of a direction change.
Garmin Edge 520 vs 820: Navigation
Whereas the two computers are quite similar in design, there are greater differences in their navigational capabilities.
Both computers have Garmin base maps pre-loaded, and they are both capable of routing along an already uploaded route created in either Garmin Connect or Strava too.
Unlike the Edge 820, though, the 520 is incapable of route planning or round trip routing actioned within the device. In other words, the Garmin Edge 820 is capable of devising a route as well as updating its directions if you go off course, making it a potentially better choice for cyclists with a sense of adventure or a talent for getting lost.
The Garmin Edge 820 can also have additional maps added to it, whereas the Edge 520 cannot.
What about Wahoo?
The Wahoo Elemnt is also an adept navigator; it has a Wahoo base map already pre-loaded and is capable of turn-by-turn navigation and guiding you round a pre-determined route which you put on the device via the Wahoo app.
Just like the Garmin Edge 820, it’s also capable of “go anywhere” routing, although Wahoo calls this its “take me anywhere” navigation, a system where you use your phone to select a destination and then the computer guides you there.
Its directions are different to Garmin’s, instead using arrows or chevrons to guide users rather than a solid line like both the 820 and 520.
Watch: Garmin buyer’s guide
Garmin Edge 520 vs 820: Training and performance
In terms of computer setup, both the Garmin Edge 820 and the Edge 520 are the same. Both computers have customisable data pages displaying stats such as distance, speed, power or cadence as well as much more performance pushing data.
Similarly, both computers have interval training and advanced workout capabilities, should you want to use Garmin’s pre-designed training sessions to help push your performance.
Clearly, they’re both very advanced computers, but there are differences. Whereas both computers are capable of conducting performance analysis, including Vo2 Max tests, FTP tracking, recovery and reporting cycling dynamics with Garmin Vector pedals, the Garmin Edge 820 is a touch more advanced in that it can conduct performance condition, lactate threshold and stress scores.
What about Wahoo?
The Wahoo Elemnt Bolt also uses data screens (you have a choice from a whopping 170) and each screen can display nine fields. You can also reduce these fields on the fly by pressing one of the side arrow keys. This allows you to go from nine data fields to just two – helpful if you’re doing a hard workout and just want to focus on the relevant numbers.
The Wahoo Elemnt Bolt is also capable of planned workouts, which do include tests such as a 20 minute or eight minute FTP tests.
It’s also possible to integrate third party training apps such as Training Peaks and display workouts on your computer for you to follow, including graphs and instructions for your next set of efforts. Wahoo says that most of the workouts are interval based using speed, cadence, heart rate or power.
Garmin Edge 520 vs 820: Phone and app compatibility
As you might expect, both the Edge 820 and the Edge 520 are engineered to partner with the Garmin Connect app. If you upload your activities via Bluetooth you’ll do it through Garmin Connect, which you can then configure to send the data straight on to Strava.
In its use of mobile phones and its app, Wahoo differs considerably to Garmin, with the Wahoo Fitness app acting almost as the brain of the computer. It’s from here you’ll configure the data screens to what you like, and by partnering your phone to your computer you’ll see them update instantaneously. As we’ve previously mentioned, you can also use the Wahoo app to navigate.
Garmin Edge 520 vs 820: Strava compatibility
We’re sure it’ll come as a relief to hear that both the Garmin Edge 820 and 520 are, of course, compatible with Strava and Strava Live segments. To get the two computers to automatically upload to the platform you need to configure your Garmin Connect account and link it with Strava.
Similarly the Wahoo Elemnt Bolt can also upload straight to Strava, and in our experience its actually faster at doing so. It’s a similar setup, simply open the app and link your Strava account.
Strava Live segments also work in much the same way as those on the Garmin models, where they have a designated page which you can configure to show either your own PR, your closest friends or the KoM.
Garmin Edge 520 vs 820: Price
At £369.99, the Garmin Edge 820 is a full £90 more expensive than the Garmin Edge 520, suggesting that those minute differences, and the touch screen, do add up.
In the end, both computers do offer serious performance pushing features, designed to benefit your training on the bike. So these aside, the decision between them will largely come down to whether you want more thorough navigational aids or not.
Meanwhile, at £199, the Wahoo Elemnt Bolt significantly undercuts the two Garmin models and still offers advanced navigation and smart design features although it can’t conduct quite as many performance tests as the two Garmin models.