Mavic Cosmic SL 45 Disc Wheelset

The Mavic Cosmic SL 45 Disc Wheelset carries one of the most recognizable names in road cycling into the disc-brake era — built on over a century of Mavic wheel engineering and decades of Cosmic-specific development that began on the roads of the Tour de France. Mavic has been building cycling products since 1889, and the Cosmic line has been a fixture in professional road racing since the 1990s, its deep-section profile a regular sight at the front of the peloton. The SL 45 Disc is Mavic's current expression of what the Cosmic should be for the majority of road cyclists: a 45mm carbon wheelset that is genuinely aerodynamic, tubeless-ready from day one, and versatile enough to cover race days, long training rides, and variable conditions without requiring a second set of wheels for everything the deeper, heavier race options can't handle.

The rim is 100% unidirectional carbon fiber, 45mm deep with a 23mm internal width — a profile wind tunnel tested to find the depth that balances aerodynamic drag reduction against real-world crosswind manageability. At 45mm, the SL 45 moves air meaningfully more efficiently than shallower wheels at road race speeds while remaining controllable in the variable conditions that make a deeper rim a liability rather than an advantage for most riders on most days. The straight extra-flat constricted steel spokes run in a 2-cross pattern front and rear, contributing to the aerodynamic efficiency by minimizing each spoke's own drag profile while maintaining consistent airflow across the wheel. The 23mm internal width opens the door to tire widths from 28mm up to 64mm, making the SL 45 an appropriate platform for a 30mm race-tuned road tire and equally suited to a 40mm mixed-terrain setup without any configuration change beyond swapping tires.

Mavic's UST — Universal Standard for Tubeless — predates most of what the road wheel industry now calls "tubeless-ready," and the implementation here is more complete than the term implies. The rim tape ships pre-installed on the wheel, and the hooked ETRTO 622x23TC standard provides a reliable seal with UST-compatible and most tubeless-ready road tires without the sealant-heavy trial-and-error that looser tubeless setups can require. Running tubeless at the widths this rim supports allows you to drop tire pressure meaningfully below what a tubed clincher setup would safely sustain at the same width — which directly reduces rolling resistance, improves traction in corners, and absorbs road vibration over long distances. The pressure range spans 47 PSI for the widest tire sizes down to 80 PSI for narrower road setups, covering the full range of tubeless road applications within the rim's design limits.

The aluminum Infinity hub is the engineering center of the wheelset. Mavic designed the hub geometry so that front and rear spoke lengths are identical — a detail with real implications for spoke tension consistency and the wheel's long-term ability to stay true under sustained load. The spoke lacing is non-contact, eliminating the friction noise that spoke crossings can produce under hard pedaling effort. Instant Drive 360 is the freehub system: a large contactless rubber seal achieves low-friction engagement with minimal parasitic drag, and the wide range of compatible end caps and sold-separately freehub bodies gives the rear hub genuine compatibility across Shimano HG road (the default), SRAM XD, Shimano MicroSpline, and both Campagnolo freehub standards. The QRM Auto bearing system self-adjusts its own preload continuously, maintaining optimal spin and eliminating play over time without requiring the rider to diagnose or service bearing preload manually — a long-term maintenance advantage that becomes meaningful after the first two or three seasons.

At $1,789, the Cosmic SL 45 Disc is built for riders who want genuine aerodynamic performance, a complete tubeless system, and hub engineering designed to stay in service reliably — not a wheelset that trades long-term durability for marginal weight savings. The 1,555g total weight — 720g front, 835g rear — is competitive for a 45mm disc-brake carbon wheelset on aluminum hubs. Mavic backs the Cosmic SL 45 with lifetime warranty eligibility. For riders upgrading stock alloy wheels on a disc road bike, or specifying a new disc build that needs to cover the full range of road riding with a single wheelset, the SL 45 Disc delivers a coherent, well-integrated answer rather than a collection of individually optimized parts.