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Karakoram Prime-X Carbon Review

The Prime X Carbon is the best offering from Karakoram
Karakoram Prime-X Carbon
Photo: Backcountry
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Price:  $950 List
Pros:  Carbon highback, improved ease of use, convenient forward lean adjuster
Cons:  Expensive, heavy, snow and ice can complicate transition to ride mode
Manufacturer:   Karakoram
By Isaac Laredo & David Reichel  ⋅  Dec 31, 2020
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67
OVERALL
SCORE


RANKED
#6 of 11
  • Uphill Performance - 20% 6
  • Weight - 10% 6
  • Transitions - 30% 6
  • Downhill Performance - 30% 8
  • Straps, Lean, Risers - 10% 7

Our Verdict

The Prime X Carbon is Karakoram's flagship splitboard binding. The highback is stunning carbon, and the rest of the binding boasts the best that Karakoram offers. Karakoram prides itself on actively joining the two halves of a splitboard to achieve great ride quality. A knock has been that this makes transitions more difficult, but the ease of transitions has been significantly improved with Ride Mode 2.0. This is our favorite Karakoram binding yet, but it is tough to justify the price when excellent bindings exist for much less.

Product Updates

The Prime X Carbon has been revised. Check out the scoop below.

December 2020

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Awards  Editors' Choice Award Editors' Choice Award Top Pick Award  
Price $950 List$385 List$540 List$575 List$830 List
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Pros Carbon highback, improved ease of use, convenient forward lean adjusterUphill and downhill performance, lightweight, good value, efficient transitions, lean adjustersLightweight, easy to transitionLightweight, fast transitions, responsive, great straps, easy to use bucklesImproved interface, downhill performance, comfortable straps, easy to deploy heel risers
Cons Expensive, heavy, snow and ice can complicate transition to ride modeHeel risers can be challenging to deploy with softer basketsHave to buy heel lock separately, soft pole baskets can struggle with riser barMight be too stiff for lighter riders, high back catches on heel cup between walk and ride modesExpensive, weight of entire system
Bottom Line The Prime X Carbon is the best and lightest binding from KarakoramSpark does it again; this high-performing model is our first choiceOur all-time favorite female-specific splitboard bindingBuilt for the sendExceptional downhill performance with refined in betweens
Rating Categories Karakoram Prime-X Carbon Spark R&D Arc Spark R&D Arc Pro - Women's Spark R&D Surge Pro Karakoram Prime-X
Uphill Performance (20%)
6
8
8
7
8
Weight (10%)
6
9
9
9
5
Transitions (30%)
6
8
8
8
7
Downhill Performance (30%)
8
8
8
8
8
Straps Lean Risers (10%)
7
8
8
8
9
Specs Karakoram Prime-X... Spark R&D Arc Spark R&D Arc Pro... Spark R&D Surge Pro Karakoram Prime-X
Measured Weight (pair) 3.16 lbs 2.8 lbs 2.4 lbs 2.7 lbs 3.18 lbs
Compatible Systems Karakoram Splitboard Clips, Prime Crampons Spark Pucks, Voile Pucks (Regular or Canted), Burton Channel Pucks, One Binding System, and Ibex Crampons Spark Pucks, Voile Pucks (Regular or Canted), Burton Channel Pucks, One Binding System, and Ibex Crampons Spark Pucks, Voile Pucks (Regular or Canted), Burton Channel Pucks, One Binding System, and Ibex Crampons Karakoram Splitboard Clips, Prime Crampons

Our Analysis and Test Results

Updates Prime X Carbon


Since we tested this binding, it has been updated with aluminum hardware to save weight, and there are dropped sidewalls, meaning the inside sidewall is lower than the outside sidewall to provide more range of motion. Notice the subtle differences in the two bindings below. The latest version is pictured first, followed by the version we tested.

Click to enlarge
Click to enlarge

We're linking to the updated version, but be aware that the following review pertains only to the previous Prime X Carbon.

Hands-On Review of the Prime X Carbon


Karakoram's Prime X Carbon represents the top of their splitboard binding line. Functioning similarly to the rest of the Karakoram bindings, the Prime X Carbon provides active joining of the two halves of a splitboard to improve performance. The Prime X Carbon is the lightest Karakoram binding and is still impressively stiff; Karakoram has tweaked their interface and improved transition speed and ease.

Uphill Performance


In tour mode, the Prime X Carbon connects to the touring interface using an axle that freely rotates similarly to a bike axle. The connection is secure and confidence-inspiring. The Prime X Carbon also climbs and tours well.

Photo: David Reichel

Weight


As the lightest offering from Karakoram, the Prime X Carbon allows you to gain the summit with more energy in reserve than any other Karakoram binding. They can achieve this by use of carbon and high-quality aluminum throughout the binding. On our scale, our size medium Prime X Carbon weighed 715 grams (per binding). For perspective, this is lighter than all of the bindings from Voile we have reviewed and lighter than other Karakoram bindings. It is heavier than the Spark R&D Arc and Surge.

Photo: David Reichel

Transitions


The transition from riding to touring was straightforward and efficient with the Prime X Carbon. Pulling down on the release lever removes the bindings from the board easily; once the splitboard is separated, the bindings grab onto the touring interface quickly. It is a nicer feature that the bindings can be locked into touring mode simply by rotating them flat to split ski (which is where gravity wants them to be anyway).

Photo: David Reichel

Transitions from touring to riding can be more challenging. The new Ride Mode 2.0, what Karakoram calls their new interface, is a significant improvement over the previous design. It definitely allows for the bindings to be clamped to board with a wider range of tolerances and handles inevitable snow on the interface better. Still, compared to the Sparks or Voile bindings, we found putting the splitboard back together was difficult when snow conditions were challenging. The difference has been reduced by Ride Mode 2.0, and with practice and a solid routine it should rarely be an issue, but the system does require a touch more snow clearing and preparation than the puck based systems we reviewed.

Downhill Performance


The entire premise of the Karakoram system is that the active joining of these bindings provides increases performance. It is clear that the bindings do securely clamp the two parts of the splitboard together; the Prime X Carbon's have rubber contact points near the edges of the splitboard that make contact with the board. Unlike the puck-based system used by Spark and Voile which only contact the splitboard through the pucks, the Prime X Carbon binding touches the board near the toes and heel. It makes sense that this should improve feedback and control. Truthfully, the Karakoram's do produce high-level performance. The feedback and control are excellent, yet it is also true that the best bindings from Spark also ride very well (and it is not clear that Karakoram's performance is better).

Straps, Lean, and Risers


Straps

The Karakoram straps work very well, as the ankle strap buckle is easy to operate and tightens effectively. Our toe strap features a traditional buckle that is fine, although you do need to accurately line up the ladder into the buckle. Despite our bindings being purchased Fall of 2018, they do not have the minimal toe strap design that is shown on some of the images of the Karakoram site.

Photo: David Reichel

Lean

We are big fans of the carbon high backs on the Prime X Carbon; the high backs are very stiff and responsive, but not painful or overly rigid. They are also damn good looking. The forward lean adjusters rotate to switch between touring and riding modes, and it's easy to operate them.

Photo: David Reichel

Risers

The Karakoram risers are intended to be operated using the basket end of your ski poles. In our experience, this mostly worked but does require precision, which can be a little tricky to master.

Photo: David Reichel

The Prime X Carbon bindings also feature a heel lock mechanism that allows the user to ski or skate without the heel of the binding coming up. This feature worked fine in our testing, but we generally do not find this feature to be necessary.

Women's Version


Karakoram offers the Prime X Carbon in a women's model. The design and materials are completely identical. The main difference is found in the sizing. The binding and its components have a women-specific sizing.

Value


The Prime X Carbon retails for over nine hundred dollars. That is far more than the next most expensive non-Karakoram binding, the Spark Surge Pro. It is tough to make a value argument for the Prime X Carbon bindings unless you are all in on the active joining technology. If you feel this feature is necessary for your splitboard performance and you want the best and lightest binding that Karakoram makes, we'd recommend giving this one a shot.

Photo: David Reichel

Conclusion


The Prime X Carbon bindings feature high performance on the skin track and on the downhill but are heavier, more complex, and expensive than other options. If you are a fan of the active joining technology or have previous experience with splitboards where you felt the riding performance was lacking, and are comfortable with somewhat more complex transitions, these bindings might be the ticket for you.

Isaac Laredo & David Reichel