New carbon wheelset called Crank Brothers Synthesis E11 comes with different tunes, spokes and widths at the front compared to the rear.

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Crank Brothers brand new Synthesis E11 is the priciest wheelset here, but also packs the most technology. Each wheel is tuned for how the front and back interact differently with rider loads and terrain, and there’s a different spoke count (28F and 32R), tensioning and rim width at opposite ends too. This detailed construction is mated to a complex, shallow carbon rim using super thick lay ups in impact zones like the rim walls and spoke bed, and way less fibre elsewhere.

Designed to be more compliant up front (and wider to better match leading tyres), the rear wheel is stiffer and thinner for tightness and reduced rolling resistance. Special USA-made 321 hubs use a freehub packing magnets to draw pawls back to reduce freewheeling friction and drag, and brace pricier, bladed, Sapim CX (rather than round) spokes to save extra wheel weight.

These wheels aren’t that light, but still accelerate fast and feel snappy bouncing between corners and picking up speed or climbing. The immediate freehub engagement is quiet and positive too, but don’t other wheels also offer all these assets for way less cash?

What’s unique to Synthesis though, is how well the front wheel grips, tracks and holds a line. It’s a big deal and allowed us to lean harder and turn more confidently than with any other test wheel on multiple tricky test track corners. The 31.5mm inside front wheel just seems to resist trembling and chattering as grip breaks away, and that isn’t with any ‘flipside’ penalty of excessive flex or vagueness in steering response either.

There’s still the overall stiffness and directness you’d expect from a carbon wheelset, but mated to a subtle ability to scrub off less speed on really sharp terrain. The overall effect is akin to your tyres feeling like they have less air pressure in how smoothly they roll, yet without any excess squish or vagueness controlling the bike.

This Synthesis is a bit of a special product and lives up to it’s billing, but whether a £2,150 upgrade for ‘ultimate’ performance is worth it, when a ‘normal’ wheelset works well and comes very close for a huge amount less cash will always be an individual choice. Crank Brothers does offer a £600 or so less money set with own brand hubs and cheaper spokes, but we can’t guarantee they’re just as good as these wheels until we ride them.