What started out as a simple navigation beacon that used lights to guide you updated to one of the most fully featured and impressively sized GPS cycling computers on the market. Introduced in Spring 2017, it took a while longer for the Hammerhead Karoo to finally get to the market, but it was worth the wait.

In a nutshell, the Karoo is a full color GPS cycling computer that runs on Android OS, but doesn’t need to be paired to anything to do what it needs to do. Which is, give you a massive amount of control over what data you see, for which bike, and guide you down the right path.

To do this, the Hammerhead team is focused exclusively on building the best possible head unit, which means continual refinement of its OS. On average, they push software updates out about every two weeks, taking advantage of their rapid rate of development. And they’ve created a simple but powerful route creation tool on their website, as well as a Chrome plugin, that let’s you make or copy routes from a variety of sources. As you’re about to read, it does a lot of things well, and does several key things that others don’t.

Karoo tech specs & details

hammerhead karoo gps cycling computer offers a large color screen and quick route navigation with easy route planning

Their first product was built mostly around Maps and Navigation. The Karoo expands on that by offering the highest map detail of anything on the market, and navigation responsiveness and real-time rerouting is faster than the competition. That’s their claim, and after using it, I’d agree. Have I tested everything out there? No, but this one’s speed is quite impressive.

hammerhead karoo gps cycling computer offers a large color screen and quick route navigation with full color touch screen operation

Features include Gorilla Glass over a high def screen, and massive attention to fit and finish and user friendliness. Buttons are offset, so as you pinch it to press the buttons on one side, you don’t accidentally push the ones on the opposite side (you know, like with an iPhone…ugh). The matte screen keeps the glare from blinding you, but the adjustable brightness (auto or manual) makes it easy to see even in broad daylight.

hammerhead karoo gps cycling computer offers a large color screen and quick route navigation with full color touch screen operation

It’s waterproof, so the lack of plug or cover for the USB charging port might look concerning, but they say many of those vestiges of older cycling computers and electronics are no longer necessary when you’re using top shelf components. They’ve subjected it to salt spray, submersion, and even frozen it in a block of ice, and it always turns out fine. So don’t sweat that open port (or do sweat on it), you won’t hurt it if it gets wet.

The Garmin-mount compatible foot that attaches it to the bar mount with is replaceable, and it comes with a tether to secure underneath it then loop around the mount…just in case. I’ve ridden it on my cyclocross test course and hit roots hard enough to slide the brake levers down the handlebar and it never popped off.

hammerhead karoo gps cycling computer offers a large color screen and quick route navigation with easy route planning

The touchscreen knows how to deal with water droplets and gloves better than most, so it won’t go nuts if your riding in the rain or sweating on the screen. And if it does get too muddy or wet, you can do everything you need to do with the physical buttons on the side, too.

Unboxing, actual weight & getting started

what accessories come with the hammerhead karoo bike computer

For $499 (or less, it’s going for $399 as of this review being posted), you get everything you need to use it. The package includes hex wrenches to install the Barfly mount, a cleaning cloth, USB cable to charge, tether strap, rubber strap to space out from a 31.8 handlebar to the mount’s 35mm design, and a SIM card sleeve and removal tool.

hammerhead karoo cycling computer actual weight

The head unit is large (see comparison photos below), and weighs in at a hefty 185g. The included mount adds 42g. The inclusion of a quality mount with the ability to add light/action camera mounts to the underside is good…not just because it’s one less accessory you’ll need to buy later, but also because the unit’s size can potentially block some handlebar mounted headlights:

the hammerhead karoo is one of the largest gps cycling computers on the market

The small Bontrager Ion front blinky light is almost obscured from oncoming traffic, which limits its benefit, so an under-bar light mount might be a good add-on depending on which lights you use.

Here’s how it compares to an iPhone 7+ (left) and older 5s (right).

hammerhead karoo gps cycling computer offers a large color screen and quick route navigation with easy route planning

Getting started

Plan on spending about 15 minutes to set it up, pair it to your sensors and do a little customization of the data screens. When you first boot it up, it’ll almost certainly look for an update and want to download it, but each update is fully packaged, so you won’t have to download multiple updates in a row to bring it up to speed. You’ll want to create an account on their website, which is free, easy and literally takes five seconds. Here are just a few of the setup screens worth point out, all of which are edited on the device…so, no need to pair an app (there isn’t one) to update or change any settings.

The home screen (left) has buttons leading to anything you’d need to edit, add or use. Click Sensors and you can add and rename your heart rate, power meter and other sensors, helping you identify each part more easily.

Click the yellow button on the bottom to start a ride, and it lets you choose which of the bikes you’re riding (right), which you set up. The beauty of this system is that you can set up the pages and screens for each bike you have based on how you use it and what you want to see for that type of ride. I added these five bikes in about 60 seconds, but then you’ll want to…

…spend some time setting up the individual pages and screens for each bike. To do that, you have a few options. Starting from the list (left), you can add or delete bikes, or click on the one you want to edit. You’ll then get options (right) for naming the bike, choosing data screens, choosing what data (if any) you want to see on the map screen, and whether or not you want it to auto-pause. This is a nice feature in that you can turn auto-pause on or off for each bike type.

Choose Data Screens (left) and you can edit each of the screens, add or subtract screens and rename or reorder them. While riding, you simply swipe left or right to move between them (or use the physical buttons on the top left of the unit).

Within each screen, you can add up to 12 data fields, BUT, you probably won’t want more than 4 or 5. As you add more fields, they stack on top of each other and the font gets smaller and smaller. I had eight on a screen and it was too much; visually very cluttered. But, you can add as many pages as you want, so just add more pages, each with a few related fields. Personally, I think it’d be nice to allow you to position them side by side or have a couple appear larger, but this works, too.

GPS, mapping & routing is amazing

The Karoo uses both local WiFi networks and optimized GPS antennae placement to help it pick up satellites faster. It is among the fastest I’ve used, which means I can get moving more quickly after turning it on.

Hammerhead Karoo lets you create map routes and gpx files for free and upload them to their gps cycling computer to get turn by turn instructions while riding

Creating a route is easy to do through their dashboard, either by importing them directly from a file, or creating one from scratch by dropping points on the map. Shown above is one of the coolest features: The ability to create a route on the Karoo from any Strava route. Their free Chrome browser plug-in will grab a Strava ride off your friends’ accounts and automatically create a route and sync it with the Karoo in the background. Technically, if it’s not a public route, you can just create the route from their ride within Strava…for free…then send that route to the Karoo, too. So, basically, any ride anyone’s done on Strava can be turned into a route to use on your Karoo.

But wait! There’s more! Not only can it put that GPX file on the head unit, it can also create turn by turn instructions from it! Normally, you need a TCX file to get the turn alerts through navigation, but Karoo converts that for you.

hammerhead karoo converts gpx into tcx files for turn by turn navigation on the bike

Another nice feature: Once you’ve added any route (from Strava or scratch or file), you can edit the ride name and details in your dashboard before they sync to Karoo. Once on the head unit, you’ll see a list of routes (left) you can choose from. When both my computer and the Karoo were on the same WiFi network (they can be on any network, they just have to be connected to the internet through WiFi), a new route synced to the device within two minutes.

To ride a route, just click on it and hit start. Or, just hit start (that yellow button that lets you pick the bike) and it’ll then give you the option to select a route or just start riding. Or, you can add a route mid-ride if you want. And once you’ve finished a ride, you can save that as a route. You have a lot of options.

Once you’re riding a route, you can set it up to display it as full screen or with up to two data fields (left, showing blank because I wasn’t moving), and the turn alerts will pop up in red. You can turn those visual alerts off and just follow the arrow and path on the map, too. If you’re on a data-only screen, the red alert can pop up there, too.

I found that the alerts happened quickly enough, but they’re visual only, which is one of my few complaints. An audible alert would be much more helpful as I’m not always looking at the screen, sometimes zoned out. If you miss a turn, it doesn’t “tell” you when to turn next, but it will highlight an alternate route on the map screen (in blue, rather than the intended route’s red highlight) to guide you back to the route. This happens really fast, which is a good thing if you’re in a city with a lot of side streets. Unfortunately, there’s not a speaker on the Karoo, but it will pair with Bluetooth headphones, so the potential for voice guidance is there in the future…as well as music controls on the screen.

This video shows some of the features and screens mentioned here in action, along with another nice feature: As soon as you finish a ride, you can save and rename it directly on the device before uploading to Strava. Which means you don’t need to do that on your computer after the fact… if you set it for manual uploads. Or just set it to automatically upload as soon as it senses it’s in range of your home WiFi network and you’ve clicked that you’ve finished the ride.

A couple other nice details: You can pinch and zoom on the map to get a broader view of your route, and if you click the “lock” icon, you can swipe to pan around the map and see outside of your exact location. Hit the lock and it jumps back to your location and puts you as the arrow in the center of the map.

how to create free gpx cycling route files for download to cycling computers

Maps are built off of a couple things, starting with Google/OpenCycleMaps for the main and satellite views, along with their own in-house mapping network operating behind the scenes to optimize mapping results for cyclists. This means trail heads, contour lines, gravel roads and other things that you want to show up for cycling routes are more likely to be included in your routes.

There’s approximately 14GB of free space, so you can download a ton of maps and rides, and it lets you download offline maps. It uses Mapbox to create the downloadable map tiles, so there’s a limitation on how big of an area that you can download at once, but you can just slide it over and download the adjacent area. The head unit will seamlessly transition from one to the next if you’re riding between them. I was able to download my hometown of Greensboro and surrounding areas before it maxed out that single download area. For now, there’s no way to download an entire state or country at a time, which is a bit of a bummer, but here’s why: Because Mapbox. But Hammerhead is working on it.

The other thing it’s currently lacking is a “take me home” feature where you can click and it’ll reroute you to get you home as quickly as possible. Why? Because you may or may not have that home area downloaded for offline use. But, when you save a route to the device, you can select to make it available Offline, which will automatically pull the map tiles it needs plus a buffer zone, which allows it to reroute you automatically without you having to download that region in advance or separately. Which means you can always follow that route backward to get back where you started.

For the same reasons, you have to have a route pre-loaded if you want turn by turn directions, and you can’t natively search for a destination on the head unit itself. Unless…you have a way of getting the Karoo on the internet, which you can do one of three ways out in the field:

  • One, it can take a SIM card with a data plan
  • Two, it can tether off your cell phone if your cell plan allows such things
  • Three, you can connect to any public WiFi network (like at a coffee shop), and the full keyboard lets you quickly and easily type in any passwords needed to connect.

hammerhead karoo gps cycling computer offers a large color screen and quick route navigation with full color touch screen operation

Anything else?

So, why is it “affordable” for such a full featured unit? Because they’re consumer direct only. The sampling of screens and features above is really just a small sample of what it can do. You can make it present some power and other data more graphically, too (see their website for examples).

As cool as all of this is, they say they’ve only built about 10% of what they want to build around this device. Which is to say there’s a lot more features coming, including third party app inclusion. Internally, they’re testing things like a Spotify app and others, but all that’s still in testing and negotiations…stay tuned. They’re also talking with popular training apps and looking at how they can integrate with those.

Strava Live Segments is coming by the end of the year, which will work either by tapping into your phone’s data, or using a SIM card inside the head unit. The advantage of having a SIM inside is that it draws less power and improves battery life.

Battery life depends on how many things you have connected to it and the screen brightness. They say you’ll safely get 7-8 hours out of it, but they’ve seen up to 11 hours. And battery optimization is yet another thing they’re continually tweaking.


hammerhead karoo gps cycling computer offers a large color screen and quick route navigation with full color touch screen operation

Prior to testing the Karoo, the Wahoo ELEMNT was my go-to head unit, and it’s the standard against which I’m judging the Karoo. Both make routing and mapping fairly easy, but in different ways. Where the Wahoo allows you to email yourself GPX and TCX files and have their smartphone app grab them from your inbox, the Karoo takes them over the air from your desktop. Both allow you to save a past ride as a route, which is handy if you want to preserve a good ride for future use. I haven’t used a Garmin in a few years, so there may be similar features there, too.

Where the Karoo sets itself apart is with the ability to use their website to create routes and save them directly to your device. For free. And you have full color mapping and the ability to save large amounts of map sections with street names for offline use. And then, if you want to add a SIM card and cell data service, you can even map and route directly from the device.

One last feature that I really like is the ability to change the screens and settings mid ride. Other cycling computers I’ve used force you to stop the ride, save or discard it, then go to the settings to change a menu screen. Or pull out your phone and do it through an app. The Karoo lets you do this directly on the device quickly, and without even pausing your ride if you don’t want to. Just hold down the bottom right button and the menu screen comes up and you can change anything you want.

If you’re looking for a full featured GPS cycling computer that makes mapping and routing as easy and clear as possible, the Karoo is worth a look. It does everything else a good cycling computer should do, and the fact that they’re already thinking months and years out in development makes me think the best is yet to come. And it’s already really good.



  1. John on

    I have a friend who has one of these. Neither of us would recommend it. Too heavy. Software is not anywhere close to Garmin experience. Metrics don’t match when run against a Garmin on the same bike. And more. NOT worth anywhere close to $500. Even if all the software bugs get ironed out it’s so heavy it’s in the realm of ridiculous. Yes. It’s that heavy.

    • Morten Reippuert on

      “Software is not anywhere close to Garmin experience”

      i would not hope so, in my experience that would equal beeing very buggy. (HW would be even worse).

      Ditched Garmin when i was on my 3rd. I’ll stick to my Polar V650 until it dies. It may not have as full a feature set but fetaures are comming (slowly) but sw and hw is super stable.

  2. Rex Haber on

    I own a Karoo and I really wanted to like it, but I have recently switched to a Garmin 520 plus which has more features, no bugs, and is about half the size and weight. The hardware for the Karoo is great, excellent touch screen that is super responsive even when you get drops of water on it. But as far as software, I felt like I was still using a prototype. Tons of bugs, turn by turn only works about half the time, the offline map issue that was mentioned, errors uploading routes, random battery drains, no power meter calibration, no Di2 support, etc. And the updates every 2-4 weeks are primarily to bandaid software bugs, not adding many new features. I cannot recommend the Karoo especially when you can get a Garmin for less money with more features and no bugs.

  3. Mark Sapey on

    I have had a Karoo since March. They have made tremendous improvements since then. I switched from a Garmin 800; the only features I miss are the sound and auto lap.
    They are continually adding new features, not as quick as some want perhaps, but there is visible progress.
    I am happy with my purchase

  4. L.Derek on

    Tyler do you really consider this a review? Do you actually think people should put down their Garmin’s and Wahoo’s to purchase this product? As a bonafide owner of this unit I am calling you out on this bs “review”. Very irresponsible. Folks if you want an honest opinion see DC Rainmaker

  5. John B on

    I’ve owned a Karoo since April. It’s fair to say the software wasn’t great at first but recent updates have fixed all the problems I had been experiencing. Even with the bugs I always got where I wanted with my data intact so I really can’t grumble. I certainly wouldn’t swap the device for the Garmin alternative and am pretty excited to see what new functionality future updates bring!

    The screen is a work of art compared to any other GPS device I’ve seen or used… I would happily recommend it.

  6. Peter Huys on

    I also own a Karoo and come frome a Garmin 705 and Garmin 1000.. The software today on the Karoo is really basic and lacks a lot compared to the Garmin. Updates are released every 2 weeks but only consist of small changes. I love my Karoo for the great screen, easy use but I hate that it lacks livetracking, smartphone connectivity, basic datafields, powermeter calibration. Its all coming they say but on a very slow pace which is a shame. Yet currently I leave my Edge 1000 at home so I sound critical but yet prefer the Karoo even with all the shortcomings it has.

  7. Matthias on

    Unfortunately I have to agree with the previous posters. The hardware is really good save for the missing sound; very sturdy device (I’ve crashed hard with it and it’s come away with only minor scratches) with great screen and buttons, very low power GPS with excellent precision; I don’t mind the weight. Unless there has been a new hardware revision, free memory is 7 GB though, not 14 GB! I wouldn’t mind an SD card slot for bigger maps.
    However, the thing where it really falls short is the software. The most misleading point about this review is the idea that you could use it with different bikes: you can create different profiles alright, provided they all share the exact same wheel diameter, which usually defeats the whole purpose. While sensors happen to work fine for what I have (nothing fancy, just a heart rate and Speed/Cadence sensor), any kind of training program is completely missing. OpenStreetMap-based turn-by-turn navigation was one of the big selling points, and while the web app to create routes works OK, it’s really basic and way behind anything like Komoot. The same goes for Karoo’s onboard navigation, just that this is also quite buggy and unstable. The best you can say about it is that its display is silky smooth, but at 480×640 all apps are.
    The Karoo’s one saving grace that has kept me from putting it on eBay after a month is the possibility to sideload Android apps. Using OSMand as a TBT navigation app you *really* get the best navigation on any bicycle computer with offline routing (Karoo needs to be online to do its route calculation, so no-go for those long tours off the grid), voice propmpts via BT headphones, up-to-date whole-country maps, satellite image backgrounds for finding those paths where no map even exists, and more. Obviously there is no integration with the rest of the software whatsoever.
    I don’t think I’m gonna sell mine any time soon, but I can really only recommend it for nerds who don’t mind the fiddling with Android. If you’e looking for a computer that you can just set up and go, a Garmin or Wahoo is still the safer choice.

  8. Tom on

    Karoo user here and ex Garmin Edge 820 owner:
    The ONE thing I want my GPS to do is navigation, and that feature was so bad on the 820 I used my phone instead.
    Karoo is a zillion times better and it let me explore thousands of miles of new routes since I use it.

    Considering what it let me achieve, I couldn’t care less what Karoo can’t do or how much it weighs.

    • Rodrigo Diaz on

      I used one on a fatbike from 5 c to -25 C. I hit a double snow ramp and did a massive endo. Separated my shoulder and broke the Garmin mount. Thing kept working.

      It was full of bugs but the biweekly updates have ironed out most things. I use it for TTs, gravel rides, Fat bike and road rides. Their updated mount is more solid, but I had a spare “dog ears” for my mega-buggy Garmin and installed it for a very solid interface.

      Last gripes: no “North locked” maps yet, and when importing routes from other users (RidewithGPS, etc.) it sometimes ‘interprets’ the route by eliminating features it doesn’t like like left turns or very dodgy roads. There are three categories of route in the builder/importer (not in the unit, but the online tool): road, gravel, MTB and it will change the route suggested. That’s good, except the blasted thing doesn’t tell you that’s going to do it.

      Overall I’m ok with this thing over my Garmin 810 that was full of bugs and would lose many rides due to freezing. Would love it if it had training plan capability as well. Not perfect, but ok.

  9. Crash Bandicoot on

    No audio prompts on a supposedly navigation focused head unit is a massive failure. I doubt many long distance riders are going to be glued to their screens for cues and I know a few randonneuring/touring organizations ban headphones. It’s a hardware failure as well which is the worst of all sins

    • Tom on

      It is actually pretty simple – I look at the screen when I see an intersection.
      Also, Karoo can tell how far I am from the next turn…

  10. dthempel on

    You’re likely to get a lot of varied feedback when talking about this device. For those of us in the “first wave” that got our devices in February and March, there have been a lot of growing pains with the software and requests for improvements that have either proven difficult or have yet to appear on the roadmap (that also disappeared). This has soured many to the device and the company as a whole.

    Some of the images on the current website are also disingenuous (at best) and don’t show the current state of the software. The review was also done on an older version of the software, as evidenced by the “Video” button/app that no longer exists.

    Bike profiles don’t really exist as depicted in this review as they don’t tie out to different sensors that might be present on different bikes. You also have to reset wheel circumference if you want accurate speed and distance via a sensor. Lot of other nits could be picked with this review.

    For a quick summary from someone who has had the device for a long time and suffered through some things: “The hardware seems good. The software leaves at lot of room for improvement and currently hamstrings the hardware.”

    “Caveat emptor” is a another option to describe things currently…

  11. Tyler on

    Ugh I hate the new barflys. I shouldn’t have to use a shim for my industry standard 31.8 bars. Just make a special one for 35m and leave the 31.8 alone.

  12. Thom on

    I leave My Karoo aside for a while iT is not finished. My wahoo is My trainings computer which is stable and has a wonderfull connection with trainingpeaks. If you are on the road for a long day the battery will not hold for longer than approx. 5 or 6 hours. For gpx routing you always need your phone to go to the internet and put the gpx file in your dashboard. So you cannot surf to a site to download. With the Sim card in the karoo iT is not possible to get sms messages or WhatsApp . IT is a nice computer but far drom finished

  13. Birdy on

    I bought a Hammerhead Karoo for my wife who wanted to dump her previous GPS (which I won’t name and designs some other nice products) but their gps was a loser. These things aren’t cheap so we usually wish list things like this if we already have one and our local shop sold me on it.

    Map detail – Excellent
    Size – Like it.
    Stable – Very!
    Adding a route has been used several time – easy
    There’s a lot covered in the review.

    We are early adopters. You took a long time to review this.

    We already own barfly’s (guess they are under new ownership as Bar Fly Bike) so it was an easy switch. I put her Prime mount on her tri bike and the one that came with it on her roadbike. We can swap out the Karoo easily among the various bikes she uses, tri, road and MTB. A little confused that you show a Bar Fly Prime. The one that came with my wife’s Karoo was a Bar Fly MAX. Super steady and lighter than their competitors. yeah, I weigh that stuff too. It’s the best mount hands down!!! Tyler must be a competitor planted to bad mouth them since that’s ALL he could say. lol You ever actually own a manufacturing company? I have, can’t please all but the guys at Barflybike are doing a fine job by us and our bikes. Besides everyone knows the industry is phasing out the 31’s.

    I only wish Hammerhead included the full barfly4 system but guess it’s the deal they made. I bought the finned cleat as an extra from barflybike website since our local shop didn’t have any. I plan to surprise my wife with a new gopro for our anniversary. Of course I want to borrow it and be able to do so easily between our barfly’s.

    As far as the GPS, it definitely has been coming along in software updates. This article is a fair one. My wife will tell you she loves no sound. She’s a multitasker and that is a feature she turns off in her car GPS or anything else that talks to her. She feels it’s distracting to her ride.

    Just wanted to weigh in on our choice to switch units. Won’t bad mouth the competitor but my wife is loving her Hammerhead Karoo and hope they continue improving the software. Happy wife, happy life!

  14. Mark Beaver on

    My biggest complaint about the Karoo was that it would not upload routes on “public” wifi – it would only work on wifi networks where you could enter the SSID and password manually – this was in March, not sure if this has been changed or not. Took it on a three week trip (and fortunately brought along my Garmin also) and couldn’t upload routes from iPad to Karoo in hotel or coffee shop networks at all – it would indicate strong signal strength and “no wifi” – frustrating. Ended up using Garmin for the last two weeks of the trip, and sent the Karoo back for a refund. No audible warnings, short battery life and immature software. Software may have improved but according to the comment above, sounds like not much.

  15. Eric on

    I’ve had a Karoo since the first (much delayed) delivery, and it’s currently sitting on my workbench with my Wahoo Bolt on the bike. Will probably sell it unless Hammerhead comes out with some dramatic improvements in the near future. I’m surprised that this review is so positive when the Karoo is missing so many features already common in most head units, even those quite a bit cheaper. The Karoo is also too big, too heavy, and has so far failed to leverage its key differentiator as an android device with potential for third party apps. After many promises of features to come, the unit still lacks Strava live segments, no advance elevation view, turn by turn navigation is flaky at best, no ability to show text messages (and probably never will), no power meter calibration, no Di2, poor map download process, terrible map contrast, map cursor is so big it blocks your view of intersections, no sound alerts (fatal flaw), buggy battery management where it will go from 30% to 0 in 5 minutes, really poor use of screen space for metrics, virtually useless routing function on the dashboard, and flaky re-routing. Even though the bolt has a very basic b/w screen, it’s easier to see metrics because of clever layout, you get all the above features, in a super compact lightweight package where you aren’t hauling a small tv around on your bars. I would never recommend a Karoo to anyone.

  16. daniel joseph peterson on

    I have owned this device for about 1400 miles. The barometer for altitude does not work. It is off on a 20 bike ride by over 500 feet for a 2500 foot climb. The support organization keeps giving me some bullshit line about how barometric pressures read differently. It’s plain wrong.I live at 5000 feet. one day it will read 4900 feet. The next day 5400 feet. Over the course of a ride it will be wrong by 500 feet.

  17. Seth on

    Cannot get this thing to pair to my HR sensor. Have rebooted with a factory rest, software updates, new batteries in HR monitors, etc. won’t connect


COMMENT HERE: (For best results, log in through Wordpress or your social media account. Anonymous/fake email comments may be unapproved or deleted. ALL first-time commenter's posts are held for moderation. Check our Comment Policy for full details.)

This site uses Akismet to reduce spam. Learn how your comment data is processed.