Editor’s Choice 2020

The front and rear wheels on a mountain bike need to do very different things. The rear needs to be stronger as it gets more of a battering, and stiffer to respond to acceleration inputs, while the front must steer accurately and find grip. Crankbrothers has recognised this, and created a wheelset where the rim, spoke count and tension is tuned to these varying roles. They use a narrower rim, more spokes and a higher tension at the rear, while the front works well with larger volume tyres. In taking a diversified approach, Crankbrothers has created a very special ride quality with impressive front wheel grip and excellent steering precision while also feeling snappy when accelerating and changing direction.

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The Crank Brothers Synthesis E here is the brand’s more affordable carbon package that opts for own brand hubs and traditional round spokes.

This adds a bit of weight, but the ride feel is almost identical, and there’s a bonus of saving over 500 quid.

Crank Brothers’ Synthesis wheels pack in a ton of technology with the front and rear being tuned differently to offer specific ride characteristics.

Each rim is specifically designed accordning to the way front and rear wheels interact with rider loads and terrain, so there’s a differ ent spoke count (28F and 32R), different tensioning and also rim width at opposite ends. The carbon lay-up comprises a complex, shallow carbon rim design using thicker fibre sections in impact zones, like rim walls and spoke bed, with less material elsewhere.

Designed to be more compliant up front (and wider at 31.5mm to better match fatter leading tyres), the rear wheel is then tauter and thinner for better acceleration and reduced rolling resistance. The wheels aren’t super light, but do accelerate super fast and also feel extremely snappy bouncing between corners and picking up speed or while climbing. The E version’s Freehub engagement isn’t the fastest, but it’s quiet and positive and never skipped a beat during testing.

What’s really special about the Synthesis package is how well the front wheel grips, tracks and holds a line. The 31.5mm front rim resists vibrating and chattering as grip breaks away, and that’s without any side-effects such as excessive flex or vagueness to steering response either. And, in a similar way to how Zipp’s Moto wheels improve off-camber hold and comfort, this is a big deal when riding, to the point the Synthesis allow you to turn harder and more confidently than any other wheel on test through multiple tricky test track corners.

Overall compliance is slightly behind Zipp’s Motos, but what we prefer is there’s still the stiffness and directness you’d expect from a carbon wheelset, especially in the much more positive and speedy feel from the rear wheel.