In The Know Cycling

The Garmin Edge 850, Wahoo Elemnt Roam 3, and 3^rd generation Hammerhead Karoo are the newest mid-sized GPS bike computers from those companies.

After riding them side by side, I have different views and recommendations on how they perform and which you should buy compared to the models that came just before them: the Edge 840, Roam V2, and Karoo 2.

In this review, I’ll tell how they do against the things I think matter most for road and gravel cycling enthusiasts. I’ll also suggest to you what I think you should do if you’re currently a Garmin or Wahoo user and you want to buy a new one, or you’re open to buying the best model for you, regardless of brand.

To give you the bottom line at the top of this review:

The Garmin Edge 850 is brighter, has a slightly improved interface, and even more features than its 840 predecessor. But aspects of its visibility, screen design, navigation, workout display, and price are inferior to those of its competitors.

Priced at US$600, €545, and £470, but on sale during November, the Edge 850 available at the following stores I recommend for their great prices, product selection, and customer satisfaction: BTD (BikeTiresDirect), 10% off w/code ITK10, Competitive Cyclist, Performance Bike, Bike-Components serving cyclists living in Europe, and Sigma Sports in the UK.

The Wahoo Roam 3 adds a touch screen, better graphics, and a more useful, though less simple, user interface than the Roam V2. However, when riding through shaded areas, its screen isn’t bright enough to display the computer’s excellent data and graphics clearly.

You can get the Roam 3 for US$465, €429, and £400 on sale at BTD (BikeTiresDirect), 10% off w/code ITK10, Competitive Cyclist, Performance Bike, Bike Components (EU), and Sigma Sports (UK).

The Karoo 3 is a world apart from Karoo 2. This latest Karoo now gives riders competitive or better navigation and workout data with screen visibility and a design that’s best-in-class. It still has some operational challenges, like start-up time, route and workout uploading and syncing, and battery life, but they don’t interfere with the in-ride experience.

Find the Karoo 3 for US$525, €500, and £450 or less at BTD (BikeTiresDirect), 10% off w/code ITK10, Competitive Cyclist, Performance Bike, Bike-Components (EU), and Sigma Sports (UK).

In The Know Cycling is ad-free, subscription-free, and reader-supported. If you want to help keep it rolling without any added cost to you, buy your gear and kit after clicking the store links on the site. When you do, we may earn an affiliate commission that will help me cover the expenses to create and publish our independent, comprehensive, and comparative reviews. Thank you, Steve. Learn more.

You can watch this review on my YouTube channel by clicking the image below.

WHAT MATTERS MOST

Instead of going through all the features, tech specs, and what’s new and different about each of these computers, I’ll compare them based on what matters most when I use them and what I believe should matter to my fellow road and gravel cycling enthusiasts.

For context, I ride 5-6x/week on solo training rides and group rides, and do gravel and road events. Bike computers are essential tools for my training and navigation when paired with apps like Training Peaks, Ride with GPS, and Strava. Fortunately, as you can see by the home screens on these bike computers, training and navigation are a major part of what they’re designed to do

I try hard to resist being a data geek or buying cycling electronics for any single feature. Finally, I’m not a mountain biker and am not reviewing these computers based on their capabilities unique to that discipline.

With that context, here’s what I think matters most when choosing between bike computers

SETTING UP THE BIKE COMPUTERS

Setting up your profiles, pages, fields, sensors, platforms, and apps on your bike computer is mainly a task you do within the first few weeks after getting your new bike computer or when you want to add a sensor or app, to make sure the computer and whatever you’ve connected it to do what you want.

If you’re switching from a previous Garmin, Wahoo, or Hammerhead model, you can transfer most of your existing setup to your new 850, Roam 3, or Karoo 3 device.

You can set up or modify a new profile and add or move fields directly on the 850 and Karoo 3 computers. You need the My Wahoo mobile app to complete all setup tasks for the Roam 3.

The Garmin Connect mobile app also provides setup capabilities. The Hammerhead mobile app doesn’t have any setup functionality.

Profiles are important if you want to use different pages and fields, such as for road, gravel, and indoor rides, or even for various types of rides on the same surface, like road training rides, group rides, and road races.

You can set up multiple profiles on the Roam 3, something you couldn’t do with the Roam V2. The My Wahoo app is also new for the latest Wahoo Roam, Bolt, and Ace computers. Although it’s not hard to use, it’s not as straightforward as the Elemnt app was that you used for the Roam and Bolt V2.

You can also connect all of the most popular training, navigation, and results tracking platforms using the Garmin Connect and My Wahoo mobile apps, and from the Hammerhead dashboard website.

COMMUNICATION OVER WI-FI TO KEY APPS

All of these computers communicate with training and navigation platforms via Wi-Fi. You download workouts and routes, for example, from Training Peaks, Ride with GPS, and Strava over Wi-Fi when you start your device, and upload and sync them when you stop a ride and reconnect to Wi-Fi.

Each generally works, though some peculiarities frustrate me at times.

For example, you need to pin your Ride With GPS routes or follow a ‘send-to-my-device’ instruction to load them onto the 850 and Karoo. In contrast, your entire library loads automatically on the Roam, and when you create or download a new route on Ride With GPS, it uploads to your Roam without any extra steps.

Likewise, I find the Karoo is the most finicky about finding my Wi-Fi network when I turn on the computer. Routes appear the fastest on the Roam, with the 850 not far behind.

The Roam shows you when it’s searching for GPS, which seems to take a while unless you’re outside. I don’t know if the others load GPS faster because they don’t display notification banners like the Roam.

VISIBILITY – ONE OF THE MOST IMPORTANT CONSIDERATIONS

A bike computer’s visibility is a crucial in-ride factor and one of the most important things I consider when judging its overall performance.

That’s why looking only at their size and specs, or examining them close-up under perfect lighting, isn’t enough.

So, I also filmed the bike computers side by side on my handlebars using a GoPro placed just below my head, with a distance, angle, and lighting as close as possible to what my eyes see.

I then zoomed in on the video from that position so you can see the computers more clearly.

 

I placed each one in my out-front mount at different times and took video on sunny and cloudy days, as well as when going in and out of shade.

Brightness

For most of my video, I set each computer to its auto-brightness level to balance screen brightness and battery life.

However, each computer has a different approach to auto-brightness.

The Edge 850 lets you set the screen’s brightness to a specific percentage of its maximum or choose the auto-brightness setting, which adjusts based on ambient light. It appears that the auto-brightness is set at around 10% of the display’s max brightness.

The Karoo also has both manual and auto brightness settings, but additionally allows you to adjust the auto-brightness intensity level. When you do that, it adapts to the ambient light based on the level you’ve selected.

Like the 850, the Karoo’s default auto brightness setting seems to be about 10% of its maximum brightness, but the maximum brightness of the 850 and Karoo appear to be different.

With the Roam 3, you can turn the screen’s backlight off, set it to automatically turn off after 5 seconds, keep it on at one of three brightness levels, or automatically adjust to ambient light in Auto or Auto Max settings.

I set the Roam to Auto Max, a level that seemed to match the brightness of the 850 and Karoo default auto-brightness settings.

In these settings, each computer was bright enough, whether in sunlight or on consistently cloudy days, to display the data and graphics clearly on its screen.

When riding on days when the light constantly changes, usually because the sun is low, your body blocks the light on your computer screen, or you’re riding through a shifting canopy of trees that cast shadows, each computer’s ability to adapt to the changing ambient light varies greatly.

In these variable light conditions, the Roam 3 doesn’t stay bright enough to be visible in the shade, the Edge 850 is good enough, and the Karoo 3 is outstanding.

The same is true when the sky is dark, usually if you’re riding at dawn or dusk, or if the midday skies are especially dark.

This is a big change from the previous models of these computers: the Roam V2 was the most visible in every light condition, while the Karoo 2 was hardly visible in any.

Contrast

I find that computer visibility is also improved by good contrast between fonts and the screen background, font size and thickness, and the use of color in the backgrounds of key fields like heart rate and power.

Here, I find the Roam 3 provides the most contrast, the 850 the least, and the Karoo falls somewhere in between.

Glare

Glare from each screen also affects how visible its data and graphics are.

The glare from the Garmin’s screen is the worst of the three and really bothered me on sunny days. You can partly fix that by switching from auto brightness to a higher manual setting, but again, it reduces the battery life.

The Karoo’s screen has some glare, but when set to the default auto-brightness mode, it reduces it enough that it’s usually not a problem.

The Roam’s screen shows no glare.

Robustness

I didn’t film these computer screens in the rain because I don’t ride in the rain. However, I did notice that if my fingertips are even slightly oily or wet, my fingerprints from swiping up and down or left and right become very visible on the Karoo and can obscure the screen underneath.

The 850 has a similar issue, although prints are less noticeable than on the Karoo. For some reason, the Roam almost never shows fingerprints.

I found myself regularly cleaning the screens before each ride and, on longer days, during stops along the ride.

Of course, this can be somewhat neutralized by using the buttons more and the touchscreen less, not sweating so much, and making sure I use my non-index fingers to spread sunscreen before I ride, even though I try to remember to wash my hands after I apply the globs of sunscreen I need to protect my fair skin.

SCREEN DESIGN – ANOTHER KEY CONSIDERATION IN YOUR CHOICE

Besides being highly visible, a screen whose design helps you mentally process its information effectively is, for me, also a key measure of its performance.

Although I’m not a user interface or user experience engineer, as a road cycling enthusiast, I interpret and respond to what these GPS computers display quite differently, given their distinct page layouts, fields, fonts, and graphics.

Garmin

Garmin seems to adopt a minimalist or “less is more” approach with the 850, similar to previous Edge models. The page layout choices and the number of fields you can add to key pages are limited, the fonts appear thin, there’s a lot of empty space on each page, and most data pages have little to no color.

 

On pages with graphics, like the map and Climb Pro, the proportions and placement of graphics and data seem inconsistent. Why display so much data and so little map detail on the map page? Why show so much map and limit the number of data fields on the Climb Pro page?

Why limit the elevation page, which shows the upcoming gradient profile, to just two data fields? Why not display it as part of a more comprehensive data page with additional data fields around it? I prefer to know there’s a climb coming and to view the profile at least a mile before it starts, so I can better manage my pace and energy as I approach.

When your radar detects a car behind you, the 850 computer, like the other Edge devices, gives you the option to choose between all-or-nothing visual alert notifications. You either see a loud, orange-colored frame around your screen that blocks parts of your data fields, or a small white dot on a black column that rises along one side of your screen.

And on the most eye-catching graphics page—the one that displays your wattage and heart rate in multicolor, moving bar charts—90% of the graphics show your trailing data, while you should be focused more on your 3-second or 5-second power and current heart rate.

I’ll discuss the 850’s workout page design, which I also think misses the mark, in the workout section of this review.

Frankly, with a few exceptions like the power and heart rate graphics page, it seems Garmin hasn’t put much effort into improving how its screen design helps you process data over the last several iterations of its Edge computers.

Karoo 3

On the other end of the spectrum, Hammerhead’s Karoo 3 seems to come from the maximalist design school. Its page layouts are very flexible, and its fonts are large and well-proportioned.

The fields resemble tiles on a blue-gray background, neatly separated and efficiently sized. You can color-code the background of your power and heart rate fields, with light gray for Zone 1-Active Recovery up to bright red for Zones 6 and 7, including Anaerobic and Sprint efforts.

The Karoo effectively balances space for data and graphics when they appear together on the same page. The use of color contrasts is strong. The map page is particularly clear, though I find the elevation profile graphic on the climb page to be larger than necessary.

And its consistent use of a yellow icon in the bottom right and a blue one in the bottom left of the map page effectively reminds users of touchscreen and button navigation options.

Roam 3

For me, the Wahoo Roam 3 has the most effective screen design.

Its fonts are the boldest, and its field spacing makes better use of the screen area than the 850 or Karoo without overcrowding.

Like the Karoo, the Roam’s fields are tiled, although the tiles are closer together. The fonts appear on a light blue-gray background, and you can color-code the backgrounds of your power and heart rate fields to match your zones.

You can view the upcoming gradient profile during a ride on the elevation or map page, with or without a loaded route, and with all the usual fields you rely on. When no route is loaded, you see the elevation profile for the road you’re currently on.

You can only get a similar gradient profile on the 850 and Karoo computers when a route is loaded.

Using the up and down buttons on the right edge of the Roam, you can also adjust the number of fields on the page you’re viewing and zoom your map in and out. This lets you stay on fewer pages for most of the data you need, rather than having to swipe left and right more often than with the 850 and Karoo.

I also find its navigation and workout interval pop-ups, which I’ll discuss later in more detail, the most visually effective among the three computers.

You can, and I have grown accustomed to each of these designs. However, my brain tends to process the data and graphics on the Roam more effectively than the Karoo, with the 850 a distant third.

OPERATION – HOW EACH COMPUTER WORKS

While each has a touch screen and buttons, they all operate with unique user interfaces, almost like different personalities.

Karoo 3

For me, and again, a lot of this is subjective, the Karoo’s touch screen is the easiest to use. You swipe left or right to move between pages, and swipe down to access the system, display, ride, and sensor settings.

The screen feels moderately responsive, not as quick as the 850, but it doesn’t react to your touch motion without a clear intention, as I frequently experienced with the 850.

The Karoo’s upper side edge buttons navigate your pages forward or back. Its lower side edge buttons do what is shown on the screen next to them, which is usually to start or stop your ride.

The Karoo’s buttons are the largest, most tactile, and have the most significant travel.

A couple of them became a little sticky after a few months, likely from a combination of sweat, gel, drink mix, and road grit. But putting the IP67-rated Karoo, with its USB-C cover in place, into a small bowl of soapy water and quickly pressing the affected buttons cleared whatever was causing the sticking and restored them to their original condition.

As with the 850, you can operate the Karoo more effectively during your rides using the touch screen rather than the buttons.

The Karoo also has two of what it calls “drawers” with information that you open by swiping them up during your ride. You can open them halfway or fully, covering part or all of the screen you were looking at before opening the drawers.

One of the drawers will open automatically just before your next interval, and another will pop open just before you begin a climb.

This is definitely helpful, but it also requires you to close the draws by swiping down to see your whole screen again, which you might not want to do just after starting a hard interval or climb. And currently, you can’t disable them.

All of these features of the Karoo’s user interface seem very intuitive, take hardly any time to learn, and simply work.

Edge 850

In contrast, the Edge 850’s UI isn’t very intuitive. But like shifting a Shimano groupset, which also isn’t intuitive, it’s what most of us grew up with, developed our muscle memory around, and until recently, when SRAM AXS shifting came along and now the Karoo and Wahoo computers, we didn’t know any better.

With the 850, you swipe left and right to go between pages, like the Karoo and Roam. If you want to use buttons to switch between pages, you need to use the up and down buttons on the bottom left edge. That requires righties to use their thumbs on those buttons, which isn’t ideal when you’re riding along. So swiping is the better option. That’s fine.

You swipe down to access a set of seemingly unrelated controls and indicators, such as sounds, brightness, battery life, GPS strength, sensors, and settings on what’s called the Status screen.

Swiping left takes you through a series of pages that access features, notifications, weather updates, Strava segments, your climb segments, Garmin wallet, light network, and trainer connection.

As one of my kids would say, it’s totally random.

As I mentioned earlier, I found the 850’s screen very sensitive. This occasionally caused me to switch places I hadn’t intended and required extra swipes to go back. Additionally, its buttons are small, less tactile, and their placement on the device doesn’t align with what I see on the screen.

I don’t find the 850’s user interface intuitive, but if I hadn’t flown the Garmin coop when Wahoos came along, it would probably feel completely natural, the way my Shimano shifting does.

Roam 3

Coming from a button-only heritage, the Roam’s touchscreen functions more as a convenient alternative rather than the primary method to operate the computer, as is the case with the Karoo and 850.

Like those devices, you swipe left and right to switch between pages, but unlike them, you can also use the right button on the front face of the computer to advance you to the next page.

You swipe down to access device settings, sensors, ride options, and notifications, and you can swipe from one to the next or use the right button to move through them.

Depending on the page you’re on, the center and left buttons on the computer face provide action options, such as starting or pausing a ride, adding a sensor, or choosing a workout or route.

 

I notice that you need to swipe the screen and press the buttons more deliberately or use a bit more pressure on the Roam than on the Karoo or 850. Overall, I think that’s a good thing, though it might not match your preferences.

I’ll discuss the processing responsiveness of each of these computers in the Navigation and Workouts sections. In general, I found that each of these bike computers responded to my swipes or button presses as quickly as I could perceive the changes on the screen, although they may differ in their actual clock speeds.

Start-up Time

I’m not too concerned about how long these computers take to start up. Putting on my shoes, topping off my tires, grabbing my water bottles, and stuffing whatever I carry in my back pockets that day takes way more time overall than it does for any of these computers to start, find a GPS signal and my Wi-Fi, and upload the day’s workout or route map.

I usually start my bike computer first and then handle everything else while it boots up and syncs.

But I realize you may do things in a different order, so I timed how long it takes each of these bike computers to start up. The Edge 850 takes 30 seconds, the Wahoo 40, and the Karoo about 45 seconds.

If you’re in a rush to get to the 6 am group ride, the 850 wakes up from sleep mode in about 3 seconds. The others don’t have a sleep mode.

I have or will explain elsewhere some of the time and functional differences involved in loading your workouts and routes. That’s part of the time it takes for these computers to be ready to ride when you use them for those purposes.

Battery Life

Battery life is another thing I don’t get too worked up about, but I know some people do. So let me go through it here.

Battery life mainly depends on your display settings. With the 850 and Karoo set to auto-brightness and Roam at auto-max, and using the same combination of power meter, radar detector, and heart rate strap sensors, the 850 and Karoo lasted about 10 hours, while the Roam lasted around 14 hours during my testing.

But the Roam isn’t as bright as the others when you go in and out of shade, and the 850 needs to be set a bit brighter to overcome its screen glare. So we’re somewhat comparing apples and oranges.

Anyway, 10 hours is enough for a week of riding for me and most enthusiasts. It’s not an issue for me to plug in my computer, radar, front light, or any other electronics once a week or the night before I know I’m going to do a 6- or 8-hour ride. Heck, most of us recharge our phones every day or two.

NAVIGATION

Navigation and Training, as Garmin calls them, or Routes and Workouts, as Wahoo and Hammerhead refer to them, are the main focus of these devices. You can see this just by looking at their prominence on key screens.

I’ll go through how these computers compare when selecting a route, loading it, what it looks like on their screens, how you get turn notifications, how they reroute, and their apparent accuracy.

Selection and Loading

Each of these bike computers lets you sort the library of uploaded routes by name, distance, upload date, or proximity to your location.

The Roam and Karoo also let you sort by elevation gain, which is useful if you want a flat course for recovery rides or if you’re looking for a lot of vert to train your anaerobic energy system.

You can also find a route by typing its name if you, like me, have over 100 routes on your computer, or if you show up 2 minutes before the group ride starts and forgot to load the route before leaving the house.

The 850 has the largest keys by far; however, it would be nice if they were arranged in QWERTY format like the others. The Karoo is passable for my fat fingertips. The Roam keys, however, are tiny, and your friends might not wait for you as you fumble trying to type in the first three or four letters of the ride name.

Once you’ve found the route you want, whether by sorting or searching, each computer loads it very quickly. You don’t need Wi-Fi access to open a route if you’ve already downloaded it to your library.

Route Display and Notifications

When it comes to how your routes are displayed and how you get notifications about upcoming turns, my take is that the Karoo is the best, the Roam is second, and the 850 isn’t as good as the others.

Part of this is due to the large screen size, which allows for a bigger map, and part of it is the graphical display – including road lines, colors, contrasts, direction arrows, and the amount of detail.

I could write a lot about why one works better for me than another, and, of course, it’s highly subjective. But let me just say that the maps pop on the Karoo and Roam, while the 850 looks dull and demands more of my focus.

I also want to see my key data fields on the map page. For example, I like to monitor my power, cadence, speed, and upcoming terrain profile when my map is up. That’s especially important when I’m pulling at the front of a group ride so I can keep a steady pace while navigating the route.

I can put all those fields and more on Karoo and Roam, but the 850 only has room for two of them.

The three computers use different methods to notify you of upcoming turns while you’re riding a course, but not on the map page.

With the Karoo 3, a small yellow overlay shows the distance and direction to your next turn on any page during your ride. You can also set it to switch to your map page about 500 feet or roughly 150 meters before the turn. After making the turn, it will revert to the previous page you had open.

On the 850, the map page appears when you approach a turn slightly earlier than on the Karoo and remains visible longer. There’s no way to completely disable this feature if you only want a turn notification banner to show up before your next turn.

The Roam 3 doesn’t have a setting to automatically switch to the map page, but it shows a turn notification banner that displays the direction, distance, and street name of your next turn about 750 feet before you reach it. That’s roughly the length of two football or soccer fields, giving you enough time to switch to the map page if you want a visual of the turn.

And you can also get audio alerts and voice directions from all three computers.

While each device offers numerous turn notification options, I find the Karoo provides the most comprehensive choices, the 850 is the most persistent about ensuring you don’t miss a turn, and the Roam notifies you in the most streamlined way.

Rerouting

The rerouting algorithms differ significantly across these bike computers.

When there’s a clear, nearby reroute, they usually suggest the same turn. But when more options are available to get you back on track, or when you don’t take the first or second option and go further away from your route, they’re more likely to suggest different directions.

In one example, I turned right instead of left at a busy intersection. The 850 and Karoo guided me to take my next left onto a short, dead-end street where I could turn around and go back in the right direction.

The Roam, perhaps knowing from its map data and the radar detector that was tracking several cars behind me at the time, that I was on a busy street and that it might not be the best time to turn across traffic. Instead, it advised me to take a right a little further up onto a short street, then take another right to get back on track.

But that initial right was onto an unpaved street full of potholes that would be fun on my gravel bike but not on the road bike I was riding. So, after feeling confident with the Roam’s instructions at first, I continued past the turn it suggested and kept going down the busy street I had originally turned onto incorrectly.

This is where the 850 basically gave up on me, showing me the names of upcoming roads on my left and right but never telling me which one I should take. The Karoo and Roam kept giving me options, any of which would work.

During this and other rerouting exercises, the Roam and Karoo quickly alerted me that I was off-course and offered instructions, while the 850 was slow to do both.

Accuracy

Reviewers who have evaluated the accuracy of the Roam 3, Karoo 3, and earlier Garmin Edge models have found that all of these devices navigate very accurately, both on and off road.

Yet, using the same routes downloaded from my Ride with GPS app and the latest cycling maps on the 850, I found it didn’t always provide the same turn instructions as the Roam and Karoo.

In the rerouting example I just described, the Garmin incorrectly told me to go right instead of left, as the others indicated. I went right, even though I knew it was wrong, and the Garmin started rerouting, even though it had told me earlier to go that way.

On my group rides, it’s not uncommon for Garmin and Wahoo devices to give a different turn instruction once or twice during a 50-mile ride. This happens even though we all download the same ride file.

It’s usually not a case of one device being right and the other wrong, as both generally lead us to the same destination eventually, just with a few different turns along the way.

TRAINING

When I’m not doing group rides or events, I’m training for them and following a structured program. In recent years, I’ve used Training Peaks, FasCat, Trainer Road, and now Intervals.icu.

As I reported in the Set Up section, the 850, Roam, and Karoo will all import workouts from the most popular training programs. The 850 can import from nearly every program, regardless of how niche it is.

The real-time data you can get about your workouts, how you’re notified of interval changes, and how you pause an interval if needed, vary quite a bit from one of these computers to another.

When you’re working hard to complete your workout as planned, whether it’s an anaerobic VO2 max interval, a long, slow Zone 2 ride, or something focused on training an energy system between those two, your bike computer can be a great partner or a mediocre one.

The Roam 3 and the Karoo 3 do a great job helping me execute my workouts effectively with their screen design, interval notifications, and pause mechanisms. The Edge 850 lags behind them on all three aspects.

Screen design

The Roam 3 lets you customize your workout screen by selecting which fields to display, arranging their positions as you like, and using the zoom-in and zoom-out buttons to view more or less of them without leaving the screen.

The color-coded backgrounds help you align your power and heart rate numbers with the zones you’re aiming to ride in. You also get a graphic at the bottom of the page that you can tap to see your current interval progress, upcoming intervals, or how far you’ve progressed in your overall workout.

You can also display this information in data fields, like the remaining time in your current interval. However, I find that visualizing the relative interval power level and the time between intervals graphically is more effective for understanding how your interval is going than just using numbers.

The target power range and the color bar indicating whether you’re within, below, or above it are too small to see easily. Wahoo copied this display from Garmin, and I don’t like how it looks on either computer.

The Garmin 850 offers fewer layout and field options on its workout screen. Unless you’re doing a workout loaded from the Training Peaks platform, the screen shows your average power as your primary interval target, with that metric in the largest font and most central field.  Alongside that field, there’s a single block graphic that fills the field in green or red, depending on whether your average interval power is within the average power target zone or not.

However, most coaches and training programs encourage you to focus on your 3 or 5-second power to guide your effort toward a specific target at every moment during each interval. Chasing an average power level over 2, 5, or even 20-minute intervals by purposely going above or below the target power for a while defeats the goal of developing the energy zone the interval is designed to train.

The secondary targets shown on the 850 workout screen, typically step distance or cadence, are seldom, if ever, a focus in modern training methods.

There are no graphics or color-coded backgrounds to assist you in mentally tracking your current interval status or see your position in the workout.

I’ve searched forums to see what others are doing to optimize the Garmin workout page and tried some third-party apps to replace the native Garmin page, but haven’t found any significantly better options.

Yes, Garmin offers a coaching program you can use with the 850 and other Edge devices, but you still need to use the same screen layout to follow their structured workouts during your rides.

The Karoo 3 opens a drawer at the bottom of your current page each time a new interval starts. It shows essential information – target power, 5-second power, remaining interval time, and your current interval number – along with color-coded zone blocks to help you see if your 5-second power is within the target range.

To monitor your performance during an interval on the Karoo, I’ve found it more effective to create and use a dedicated page for your workouts, reserving the drawer solely for interval notifications.

You can select the fields you want and add graphics at the bottom that display your progress in the current interval or show the relative power output and remaining time of your upcoming intervals, similar to the display on the Roam.

You can also put a field on that page that displays your target power range alongside your current, 3-second, or 5-second power in a much larger font than the ones on the Wahoo and Garmin.

Interval Notification

The Karoo drawer that opens at the start of each interval is the notification. However, you need to close the drawer by swiping it down to see the dedicated workout page or whatever other page you had open when the new interval begins.

I find it a bit distracting to do that just seconds after starting a new interval, especially when I’m powering up to a harder level.

You can leave the drawer open, for example, it can overlay on your map page if you also want that visible, but I try not to do intervals, or at least short ones, on roads I don’t know and need to follow a map.

The Roam’s interval notification—white, bold fonts on a black background—is visually very effective at getting my attention without distracting from completing a hard interval or gearing up to start the next one after a recovery segment.

The notification appears 10 seconds before the interval starts and begins beeping with a 5-second countdown. It then disappears once the interval begins.

Your screen doesn’t switch you to the workout page; none of the computers do. So, if you don’t already have the workout page open, you will need to do that manually on each computer.

The 850 notification is similar to the Roam, except its presentation – a square pop-up block with black font on a light background – doesn’t stand out much from the same font and background color combination you’ll see on most of the 850 pages.

Pausing

When you need to pause your workout during an interval because you reach an intersection, encounter traffic, or something else prevents you from continuing, the 850 requires you to swipe up from your workout screen and touch the pause button.

When you’re ready to resume, you touch the button again and swipe down to go back to your workout screen.

When the Karoo’s workout drawer is open, you can press the pause button that’s part of the drawer to stop and resume the interval. If the drawer isn’t open, swipe it open, then press the pause button, just like you do with the 850.

You can add a pause button or what Hammerhead calls a Control field on your dedicated workout page, and you only need to touch it to pause and resume your interval when that page is open.

If you’re not having a good day or running short of time, you can skip intervals using the forward touch button to the right of the pause button on the 850, or on a dedicated Karoo workout page.

If you are having such a good time that you want to go back and do one of your intervals again, you touch the back button to the left of the pause one on the same screen.

With the Roam, you can use the three physical buttons on the bottom face of the computer to pause, skip forward, or skip backward. No swiping or touching the screen is needed. And whatever page you have open stays open while you’re doing any of this.

If I’m hauling down the road with my heart pounding and need to pause during an interval, I find it a whole lot easier to press a physical button that I can find and feel almost without looking than to swipe up, look down, and hope my finger lands on a touch screen button squarely the first time.

FEATURES

While navigation and training are the primary functions of a GPS bike computer like the Edge 850, Roam 3, and Karoo 3, these devices also provide additional features that can help you decide between them.

Each has a climbing feature that became a key part of their appeal when first introduced on Edge devices, then on Wahoo computers, and later on the Karoo 2.

Like other aspects of their performance, the effectiveness of each climbing feature is subjective, but here’s my take on them.

If climbing is your thing, the Roam has the most helpful climbing page. You can select the fields you want, including some that the 850 and Karoo don’t offer, like the time remaining until you reach the summit instead of just the number of vertical feet left.

The Roam page has a better balance between the climb graphic and data fields compared to the Karoo, which I find allocates too much space to the graphic.

The 850 includes a map graphic on its climb page that clutters an already small screen. Only four fields can be shown on the 850 map page, and the ascent remaining and elevation numbers—part of the climb graphic—are so tiny that they’re hard to see, especially when you’re pushing yourself during the climb.

Another popular feature on some of these computers is the ability to view wind speed, direction, and weather in real time, as well as upcoming conditions. This can be very helpful if you’re out for a long day and the weather is likely to change a lot during your ride.

The 850 offers the most comprehensive weather information through a widget or glance you can access on the page that opens when you start the computer. It’s not something you want to try to look at during a ride but can be very helpful before you head out or when you take a break.

Both the 850 and Karoo also let you add third-party apps for wind and weather.

You can load the WindField and AccuWeather apps on the 850 and display some of their information as a field on your profile pages. The former works quite well, while the latter receives poor ratings.

The Karoo’s extensions page gives you access to My Windsock and Epic Ride Weather, both pretty good in my experience.

Roam doesn’t have any built-in or third-party weather apps for the computer. You’ll need to use your smartphone to get wind and weather updates.

It has a unique ability to save battery life on your Garmin Varia, Wahoo Trackr, or any ANT+ radar detector. You can use its autolight settings to turn off the light 1, 5, or 10 seconds after the last car passes you.

I covered this in detail in my video comparing the Varia and Trackr radar lights, which you can see by clicking on the image below.

Beyond those features, there’s the digital bell that each of these computers has, which some reviewers can’t stop talking about. I never use it. I prefer human interaction, like calling out “on your left,” then thanking them for moving over and wishing them a good day.

Garmin offers a wide range of features that the others don’t.

It offers the Garmin Coach feature, which provides training programs, tracks your hydration, nutrition, and core temperature, and measures your VO2 max, along with various Garmin-specific metrics.

I’m not sure how good they are. The training plans don’t adapt to your training performance the way many others do today, thanks to machine learning.

And I’m skeptical of how accurately a bike computer measures my VO2 max after my first ride, especially if it never changes after several months of training. That was my experience with the Edge 1050.

You can see my video comparing that computer and the Wahoo Ace by clicking on the image below.

By the way, if you were wondering if the Karoo is more similar in size to the 1050 and Ace than the 850 and Roam, these photos give you a good perspective on their relative sizes.

Garmin also offers a wide range of tracking and alert features. These include live tracking, group tracking, and accident notifications to your designated emergency contact. It also provides sharp bend, high-traffic, road hazard, and pothole alerts.

You can also receive alerts if your heart rate, time, or distance on the bike exceeds your set goals for those metrics, or if your cadence or power is too high or low relative to your workout targets.

With its custom alerts, you can even be reminded to eat, call your mother, or do anything your heart desires.

Garmin also has an ecosystem of devices and a store full of third-party apps written for its Edge computers and other devices.

Personally, I don’t find the 850’s unique features, the Garmin ecosystem, or most third-party apps appealing.

You might find some of these features useful for your riding and valuable enough that you’ll want to buy the 850 to get them, regardless of how the 850 performs—good or bad—on the things I believe matter most and have discussed in this video.

That’s okay. Many people buy a Garmin bike computer for its features and to stay connected within the Garmin ecosystem. If you’re one of them, I’d love to hear about your experience in the comments below and read what I’m missing.

VALUE

The Garmin Edge 850 is the most expensive of these bike computers, priced at US$600, €545, and £470. The Hammerhead Karoo 3 is the next most expensive at US$525, €500, and £450. The Wahoo Elemnt Roam 3 is the least expensive at US$465, €429, and £400.

But many of these computers are currently discounted by 10% or more at the stores I link to at the top of this review.

Overall, I rate the Karoo’s performance slightly better than the Roam and both significantly better than the 850.

Considering their performance and prices, I value the Karoo and Roam equally, and each provides better value than the 850, based on my testing.

SUMMARY AND RECOMMENDATIONS

If you’ve used Garmin computers for a long time and are comfortable with their screen design, how they operate, and their approach to navigation and training, and you like having a device that’s part of the Garmin ecosystem with some unique features, then the ability to make the 850’s screen brighter than earlier models is a significant improvement over the Garmin you may currently own.

If you’re due for a new computer and want to stay with Garmin, the Edge 850 will be an upgrade.

If you’re not committed to Garmin, whether you have one or not, you can get a better experience with the latest Roam or Karoo.

If you use a Wahoo Roam V2 or Bolt V2, the Roam 3 includes significant upgrades. Notably, the touchscreen, user interface, overall screen design, and navigation and workout screens, along with the use of color and graphics, are all improved compared to earlier models.

Although slightly more complex to use than earlier Wahoo models, the Roam 3 is more intuitive than the 850 or Karoo. It also effectively uses its buttons to zoom the map, change the number of fields per page, and pause workout intervals.

But if you ride in and out of the shade often or on many overcast days, you’ll be disappointed that the Roam 3’s screen isn’t as visible as earlier Wahoos or as the 850 or Karoo 3. You might want to stick with your Roam V2 or switch to the Karoo.

The Karoo 3 has the largest and most visible screen, and its screen design is nearly as good as the Wahoo Roam 3.

It’s a step function better than the Karoo 2, and I think the best performer and one of the best values if you’re buying your first mid-sized GPS bike computer. It’s also the one I’d recommend if you are open to moving on from a Garmin or if you ride in an environment where the Roam 3’s screen won’t be bright enough.

It still has some quirks and bugs that come with being a relatively new OS, but Hammerhead has shown the ability to address them in the past with its regular middleware updates.

I’ve now switched to the Karoo 3 as my primary bike computer, after using and loving the Roam V2 for the last three or four years and Garmin computers for many years before that.

You can order these bike computers at stores I recommend for their great pricing, product selection, and customer satisfaction by clicking the links below. When you do, you’ll also support the site’s independent, ad-free, and subscription-free reviews.

Garmin Edge 850, priced at US$600, €545, and £470 from BTD (BikeTiresDirect), 10% off w/code ITK10, Competitive Cyclist, Performance Bike, Bike-Components serving cyclists living in Europe, and Sigma Sports in the UK.

Wahoo Elemnt Roam 3, priced at US$465, €429, and £400 from BTD (BikeTiresDirect), 10% off w/code ITK10, Competitive Cyclist, Performance Bike, Bike Components (EU), and Sigma Sports (UK).

Hammerhead Karoo 3, priced at US$525, €500, and £450 from BTD (BikeTiresDirect), 10% off w/code ITK10, Competitive Cyclist, Performance Bike, Bike-Components (EU), and Sigma Sports (UK).

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Thanks, and enjoy your rides safely! Cheers, Steve