Crank Brothers Highline is a totally new design. Crank Brothers are so confident about the performance that it’s offering a three-year guarantee.

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The Highline uses a fully-sealed aluminium cartridge that’s not serviceable, but can be removed easily from the seat clamp end if anything goes awry (spoiler alert: It didn’t.) This cartridge uses a threaded spiral plunger to let hydraulic fluid pass and allow the post to compress or extend. By metering the oil flow with this twisting, rotary design, rather than a tapered needle or pin, ensures the force needed to actuate the post is consistent at the remote, regardless of hydraulic pressure.

This level of detail and material choice extends to how the stanchion slides through high-end Trelleborg polymer seals and the ‘keyed’ inner part cycles in special IGUS LL bushings. For maximum smoothness in the lever, the post ships with Jagwire’s priciest Ultra-Slick inner cable and housing too.

Crank Brothers solid bar remote is sorted too. Using a ball and socket joint – that can orientate in any direction – lets you position it right where you want. It also stays firm under the strongest thumbs and sits on either side of the bar to suit all gear and brake lever preferences.

The Highline is very smooth and has remained solid and twist-free after extended use in all conditions. Multiple testers have had zero reliability issues, although the inner cable became slightly sensitive to tension and alignment in one of the more curvaceous internally-routed frames on the market, and the return speed may not be as fast as some people like. The 150mm has a deeper insertion than some too, which might be an issue if your frame doesn’t have a long, straight seat tube. Overall, Crank Brothers has totally nailed the Highline’s performance, and the price is fair for the quality on offer.