K–EDGE Hammerhead computer mounts review – the ultimate Karoo connectors for MTB, gravel and road riders

US made K–EDGE mounts have been the pro 'go-to' for Garmin computer mounts and now they’ve added equally tough and even more secure Hammerhead versions to its line up

K–EDGE Hammerhead computer mounts
(Image: © Guy Kesteven)

BikePerfect Verdict

The most secure, well positioned Hammerhead Karoo mounts you can buy and well worth the extra cost and weight for rougher riding.


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    Super tough US made construction

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    Excellent computer security

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    Low computer stack height

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    Easy angle adjustment

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    Over stem mount position is great for visibility and knee clearance


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    Heavier and more expensive than plastic options

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    Color options are limited on the ‘out front’ mount

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    No 35mm clamp option on the ‘out front’ mount

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In a world of plastic or 3D printed mounts, the US-made CNC machined alloy mounts from K-EDGE have always stood out for their strength, security and stiffness. That’s made them the go-to for the best MTB Garmin computer holders for pro riders both on and off-road, and now they’ve created dedicated mounts for Hammerhead computers too.

K–EDGE Hammerhead computer mount

The Hammerhead Max XL Combo mount is a classic ‘out front’ design that clamps onto round section 31.8mm bars (Image credit: GuyKesTV)

Design and specification

I tested two different mounts from K–EDGE. The Hammerhead Max XL combo mount is a classic 'out front' design that bolts onto round bars. The curved hook of the forward arm then 'reaches across' to align the computer screen with your stem. 

Rather than the normal round 'Garmin' mount, this version uses a distinctive teardrop plate (like the 'fifth wheel' the semi-trailer slides onto on an articulated truck) mount to sync with the underside of your Hammerhead Karoo head unit. This 'Combo' mount also has a bolt-on mount on the underside for the best MTB action cameras or lights up to 242g.

The neatly machined arm is lifetime warrantied against manufacturing defects (not crashes) and the very accurate hinged clamp secures with a single bolt. While the Garmin Race mount comes in Black, Red, Blue or Red and Blue options the Hammerhead is only available in Black with laser-etched logos. There’s only a 31.8mm clamp version currently too, so 35mm MTB bar users won’t be able to use it.

That’s where the Hammerhead Boost stem mount comes in. Rather than a bar clamp, this uses a 5mm deep fork steerer spacer to clamp under the headset top cap. A short 1cm rise arm then lifts the bolt on the teardrop Hammerhead plate up above the level of a rising stem or front plate bolt knobbles. Because the plate and riser arm are bolted together rather than machined from one piece like Nukeproof and other designs, it means you can adjust the computer angle to suit. Again it’s only available in Black with laser-etched logos.

K–EDGE Hammerhead stem mount

The K–EDGE Hammerhead Boost stem mount fits above the stem in place of a 5mm spacer (Image credit: GuyKesTV)


While Hammerhead’s Karoo computer comes with a clip-in Garmin-style mount, using the teardrop mount has three clear advantages. It’s a lot more secure in terms of not unclipping when knocked sideways slightly. Instead you have to twist it sideways with a decent amount of effort and then slide it forward. So while I’ve regularly knocked Hammerheads off Garmin mounts, I’ve had zero issues with accidental ejection with either K–EDGE mount. That includes several crashes where the mount has been knocked out of the alignment but the computer hasn’t budged. 

The ability to change the angle of the computer slightly without triggering the release (like a float on a pedal cleat), also means you can get your computer straight on swept-back bars.

The Hammerhead mount is also much lower so it looks neater – particularly above the stem – and again there’s less danger of it being knocked. The forward throw on the Boost stem mount also makes the computer easier to see compared to 'straight onto the steerer' mounts I’ve used before. There’s less chance you’ll knock it with your knee while climbing or crashing too.

The only real downsides are cost and weight compared to plastic mounts. Having snapped the official Hammerhead plastic mount supplied with the Karoo within a few weeks I reckon they’re worth it though. Plus, if you already have a Garmin-style K–EDGE mount you can get 'fifth wheel' style converter inserts for $12.99.

K–EDGE Hammerhead stem mount

The Boost mount is particularly good for MTBs and gravel bikes weird shaped bars (Image credit: GuyKesTV)


You could just fit a convertor plate to your Hammerhead and pick from a huge range of Garmin-style computer mounts. However, these new K–EDGE mounts take all the extra security and adjustable angle advantages of the Karoo 'Fifth wheel' mount and reinforce them with the legendary tough and secure performance K–EDGE are renowned for.

They do cost and weigh more than plastic mounts but I reckon they’re well worth it.

GoPro mount on K-EDGE

The K–EDGE Hammerhead Max XL Combo has a GoPro or light mount bolted onto the underside  (Image credit: GuyKesTV)

Tech specs: K–EDGE Hammerhead Max XL Combo mount

  • Price: $72.99 / £89.99
  • Sizes: 31.8mm only
  • Color: Black only
  • Weight: 64g

Tech specs: K–EDGE Hammerhead Boost stem mount

  • Price: $52.99 / £67.99 
  • Sizes: 1.25-inch steerer only
  • Color: Black only
  • Weight: 26g
Guy Kesteven

Guy has been working on Bike Perfect since we launched in 2019. Hatched in Yorkshire he's been hardened by riding round it in all weathers since he was a kid. He spent a few years working in bike shops and warehouses before starting writing and testing for bike mags in 1996. Since then he’s written several million words about several thousand test bikes and a ridiculous amount of riding gear. To make sure he rarely sleeps and to fund his custom tandem habit, he’s also penned a handful of bike-related books and talks to a GoPro for YouTube, too.

Current rides: Cervelo ZFS-5, Forbidden Druid V2, Specialized Chisel, custom Nicolai enduro tandem, Landescape/Swallow custom gravel tandem

Height: 180cm

Weight: 69kg