DUKE RIM SIERRA ÆRA W 42

Sierra Æra W42 is the all-round Wide profile in the Sierra Æra family: a rim first designed for the front wheel, but also fully usable as a matched W42/W42 setup for racers looking for stable, consistent and forgiving aero behaviour.

With its 42 mm depth and 43 mm external width, it brings the Æra Wide logic to all-round gravel racing. The gain does not come from excessive depth, but from the alignment between tyre and rim, which improves the aero transition while limiting unnecessary wind exposure.

Its signature Æra relief, developed using CFD, reduces drag by up to 10% compared with a smooth rim of the same depth. On a front wheel, this optimisation is especially relevant: the airflow is cleaner there, and crosswind stability remains critical to keep the bike easy to handle.

Built with the SLR5 process, Sierra Æra W42 combines Toray T1100 fibres, aerospace-grade resin and a high-precision lay-up. At 420 g, it keeps weight contained for a Wide aero rim, with a structure designed for fast gravel and long races.

DRC (Dynamic Response Comfort) filters vibration and stabilises the wheel on fast tracks as well as rougher sectors. SpokeCore moulded spoke holes reinforce structural homogeneity, while wide AntiPinch beads allow lower gravel pressures to be used with greater safety.

With 28 mm internal width and 43 mm external width, Sierra Æra W42 is optimised for 40 to 45 mm tyres in aero use. It remains genuinely compatible with wide sections, allowing the build to be adapted depending on the desired level of comfort, grip or efficiency.

As a front wheel paired with an Æra 48 rear, it forms our most versatile gravel race combo. As a W42/W42 wheelset, it prioritises symmetry, stability and ease of use. A solution to ride fast without making the bike nervous, on varied races where average speed matters as much as control.