Reviewed: Hammerhead Karoo 2

A pioneer in maximalist cycling computers goes on a diet with a game-changing upgrade.

Review Rating


Hammerhead succeeded in slimming down this feature-packed computer while retaining the bold visuals, excellent touchscreen, and killer navigation, but data junkies might be disappointed.


(Now) manageable size
Stunning touch display
Unparalleled navigation tools
Well-thought-out data viz


Data analysis is essentially nonexistent
Still a few bugs
No app (though not entirely necessary)
Long startup time







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Roughly two years ago, Hammerhead released their first edition of the Karoo. It was a bold move from a new company not named Garmin or Wahoo to come out with what amounts to a smartphonecomputer in an already pretty crowded market. The long and short of it was that the original Karoo was bursting with features, had a stunning color touchscreen, and had great visualization, but it was plagued by a clumsy footprint and beefy weight. It was the perfect device for anyone who wanted to do everything on their handlebars, but it also wouldn’t allow you to do much else. Because of this, the announcement of the Hammerhead Karoo 2 a few months ago was met with both welcome, and, maybe trepidation. Let’s see what we’ve got.

Hammerhead Karoo 2: The Basics

For those unfamiliar with the premise behind the Karoo and the Karoo 2, this is a touchscreen cycling computer that is basically a smartphone. You can set everything up in the Karoo itself, you can even add a SIM card to download map data, upload rides, and more—making it basically a smartphone in almost every sense of the word. It has offline navigation, as-you-go maps, routing, upcoming elevation with a preloaded route, and a host of data screens and fields that you’d find on most higher-end cycling computers right now (think Wahoo’s ELEMNT Roam with a touchscreen or Garmin’s Edge 1030 Plus). The screen itself is unique in the cycling computer world with a 3.2-inch, nearly-300dpi resolution, meaning the colors and details are nearly on par with an iPhone (which, for reference, has 326-456dpi depending on the model). There is no app to set it up, because really it is a smartphone, but Hammerhead does have a web-based dashboard to help manage routes, rides, and more. Like most cycling computers, it also uses WiFi or Bluetooth to upload rides and download routes.

Hammerhead Karoo 2: The Good

If navigation and “geography”—things like elevation, routes, and turn-by-turn directions are important to you, there isn’t a better computer out there. The in-ride maps update smoothly and even have a 3D view function—like something you’d find on a smartphone. The elevation features are similarly impressive, showing upcoming gain/loss on preloaded routes and a plot of where you’ve been. Similarly, if you’re a Strava segment hunter, the addition of Strava live segments make this an invaluable tool for bagging big game KOMs as you go. 

The other big selling point for the Karoo 2 is its data viz. Think of the difference between an old-school table of numbers in a newspaper and a beautiful infographic you might find in a glossy publication like Wired. Those talented designers spend a lot of time trying to make complex information look simple and intuitive, and the Hammerhead team has done the same. In particular the heart-rate and power zone visualizations use either a very cool “circular zone” or “zone gauge” graphic to see your zones at a fast glance. The Di2 gear display graphic is also very impressive. While you could write these things off as novelty, anyone who trains often on a bike knows you need to identify this data super quickly at a fast glance to keep your eyes on the road while you suffer. Wahoo does this with LED bars above and to the side of its screen; Hammerhead does this with fast-refreshing, brilliantly colored graphics.

Both of the above big “wins” are due largely in part to a dazzling display and some very graphically minded developers who put visuals at the top of their priority list. Both the navigation (for directions, route finding, and/or Strava Live) and the data viz strengths lie at the heart of some novel hardware and some well-thought out graphical design. 

Unrelatedly, the slimming down from the Karoo 1 to the Karoo 2 finally makes this something that’ll fit on all handlebars, whether you’ve got aerobars or other devices like lights, and won’t shake itself loose under the stress of its own weight.

Hammerhead Karoo 2: The Alright

In terms of navigation, there’s not much that can beat this computer, but in terms of raw data analysis—particularly post-ride—it comes up very short. In fact, after a ride is finished you’re only given basic stats on things like elevation (ascent, descent, and max), power (average, max, normalized, TSS, IF, and KJ), cadence (average and max), and heart rate (average and max). No time in zones, no graphics, not even a map of the route when you view it in the device itself. The web app dashboard has a ride map, but not much else. It appears that Hammerhead asks its users to rely on external services like TrainingPeaks, Strava, etc. to do much of the data heavy lifting, but it’s surprising after using computers (and their accompanying web apps) from brands like Garmin and Wahoo. In a way, it almost feels like something is missing. 

Other little nitpicky things like a few bugs with speed and elevation on our unit will probably be ironed out in software updates, but in that same vein the Karoo 2’s startup load time is still quite long when compared to other computers. We were also not thrilled with the included bar mount setup and would suggest getting the Garmin-mount “quarter turn” adaptor immediately with purchase.

Hammerhead Karoo 2: The Conclusions

In terms of value, even though this is not a cheap computer at $400, it still easily punches against navigation-heavy touchscreen computers like the Edge 1080 Plus that cost considerably more. Even when going head-to-head with the non-touch, smaller-screened ELEMNT Roam at roughly the same cost, the Karoo 2 is a no-brainer for “nav heads.” Whereas the old Karoo was limited by it’s gargantuan and unconventional footprint/weight, this update solves those issues perfectly. On the other hand, if you’re a big data junkie who likes to admire your sweat equity right after a ride, you’ll be a little disappointed with this setup. It’s possible that Hammerhead assumes that their customers will all use other services for post-ride analysis, but for something that otherwise feels so self reliant—and has such incredible data viz for in-ride display—it’s an odd omission.

All in all, this is a fantastic computer that will no doubt get better with age, as Hammerhead’s commitment to software updates nearly guarantees. The issues with bugs and even with light post-ride data could either be updated away or (in terms of the analysis) be a non-issue with other companion software/services. Either way, this is a great computer with some truly novel hardware and software that it’s unlikely other brands will be able to replicate anytime soon. The trickiest thing about this computer will likely be getting your hands on one.

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