THE LAB – Hammerhead Karoo 2 – The Karoo 2 bike computer from Hammerhead on test

Faster, better and easier than the competition – that is the Hammerhead Karoo 2’s goal. Is this possible to do without losing sight of the primary criteria – ease of use and high reliability? We put the Karoo 2 through its paces and let you know how the Calfornian has fared.

Hammerhead Karoo 2 | Tester Christoph | Duration 4 weeks | Price € 399 | Weight 133 g | Intended use Navigation, tracking, indoor training | Manufacturer’s website

Many great things come from the Golden State, including films, smartphones, bikes from Specialized or Santa Cruz, and now a bike computer. The folks at Hammerhead share our belief that cycling has a positive impact on everyone who loves to pedal. In an effort to inspire more people to take up the sport, they have created bike computers that aim to outdo the competition from the likes of Garmin and Wahoo. In THE LAB, we find out if the second generation lives up to that promise.

The Hammerhead Karoo 2 comes in a comprehensive package, which includes useful accessories. It features a front mount suitable for a 31.8 mm handlebar and an adapter for quarter-turn mounts. This type of mount is also used by Wahoo and Garmin, so you can use your existing accessories when switching from another manufacturer to Hammerhead. To get you up and running quickly, the package also includes a lanyard for extra safety and a high-quality USB-A to USB-C cable.
However, the USB-C port is covered with a rubber plug to protect it from water and dirt. Unfortunately, this plug is not securely attached to the device and, from our experience, tends to get lost easily.

Cancel your therapist – No more fear of losing things!

The Hammerhead’s specific locking mechanism consists of “push in” to lock and “twist” to release. Once the Karoo 2 is locked into the mount, it is virtually impossible to lose; it sits rock solid and can only be unlocked with a little force. Afraid of losing your bike computer on bumpy rides? Relax, no need to worry!

The hardware makes a good impression. A wrap-around rubber strip protects the left, right and front sides from minor drops. The rubber strip also widens to accommodate the Karoo 2’s mechanical buttons. There are two on each side. The top two are used for menu selection, the bottom two for input. We didn’t let it drop, but we would expect that the Karoo 2 would survive a fall from handlebar height. As long as your little companion doesn’t fall awkwardly onto the screen, it should get away with just a few scratches.

Plug? Which plug?
From left to right: USB-C port and replacement plug. Not in the picture: the original plug, which got lost pretty quickly.
It fits
The mount combines “push in” to lock and “twist” to release, which works perfectly.

Setting up without an app – Is that possible?

If you’re looking for a Hammerhead app to set things up, you might be in for a disappointment. The good news is that you don’t need any app (really!). Just turn the Karoo 2 on, connect it to your Wi-Fi network, and use the QR code on the screen to link to your Hammerhead account. And you’re good to go.

If you have an existing Hammerhead account and it’s already connected to Strava, Komoot – or whatever you use for tracking or route planning – you’re all set.

Once you start the device, you’ll be taken to the home screen, where you can choose in which mode you want to use the Karoo 2. Your options include:

  • Basic Profile
  • Heart Rate
  • Power + HR
  • Indoor Ride

These are pre-configured display modes that have been optimised for specific purposes. As everything is freely configurable and you can even delete the four profiles, we won’t go into detail here. Our recommendation: Customise the profiles to suit your needs.

The 3.2″ display and the response time remind us of an old-fashioned smartphone. However, the Karoo 2 is not inferior to Garmin and Wahoo in terms of performance. On the contrary, the display excels in pixel density and colour representation. The small keyboard works surprisingly well and even entering WLAN passwords is no problem.

In terms of connectivity, the Hammerhead is very well served. As well as Wi-Fi, Bluetooth and GPS, it also has ANT+. To make you more independent on the road, there is also a SIM module that supports up to 4G network speeds. In our case, connecting to various sensors via ANT+ worked without a hitch, and the familiar wireless networks were quickly found and connected.

Basic Profile
The Basic Profile takes you straight to the map view and from there to your routes.

Let’s go!

With a boot time of well under a minute, the Karoo 2 is quickly ready to use and lets you choose your preferred profile. The Basic Profile takes you straight to a map view with a speedometer and the option to access synchronised routes with a simple tap. Here you can select the route you want – or synchronise it first, which requires an Internet connection. If you prefer not to use the built-in SIM slot, you can opt for Wi-Fi or a hotspot.
Select a route, confirm and off you go.

Operating the Hammerhead while riding works well, as long as you only need the button functions. The top buttons allow you to switch between the pages you have set up. Two of them are preconfigured, but you can create up to 12 custom pages. The bottom right button pauses the recording. The bottom left button takes you to a bird’s eye view of the map and then step by step incrementally back to the “navigation level”. This is useful, as zooming with two fingers on the move is rather fiddly and not recommended! One notable feature: if you want to zoom in closer to your position, a double tap is all you need.

Touch me.
The buttons are easy to feel and operate.

Tastes vary, and so do external conditions

The battery life suffices for day trips. After about 7 hours of riding, the battery level was usually around 40%. For longer trips, you should consider a power bank or look at the competition from Garmin and Wahoo. In rainy conditions, you can lock the screen to prevent accidental entries. However, rain undeniably affects the touchscreen experience, which is a bit of a letdown.

Our conclusion on the Hammerhead Karoo 2

The Hammerhead Karoo 2 aims to fill a niche in the bike computer market with smartphone-style user-friendliness, but falls somewhat short. While the operation is efficient, it doesn’t quite match up to a smartphone, and the battery life struggles to keep pace with the competition. Nevertheless, if you want a bike computer with a large screen and touch controls, and don’t usually go on extra-long rides, the Karoo 2 could be a fit for you.


  • great display
  • easy to set up


  • battery life
  • operation in the rain
  • USB-C port rubber plug is easier to lose than Nemo

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Words: Christoph Staudinger Photos: Antonia Feder