Zipp 858 NSW Tubeless Disc Rear Wheel

Most deep-section wheels force a compromise: push the rim depth high enough for real aerodynamic performance and crosswind handling becomes a liability. The Zipp 858 NSW Tubeless Disc Rear Wheel was engineered to break that tradeoff. With an undulating 82–85mm Sawtooth rim profile, Hyperfoil nodes, and HexFin ABLC dimple geometry, the 858 NSW simultaneously reduces aerodynamic drag and side force — a combination that conventional deep-section wheels, smooth and constant-depth, can't achieve. This is Zipp's highest-performing aero wheel, designed for riders who demand maximum speed at the deepest end of the rim-depth spectrum.

The aerodynamic system starts with the Sawtooth profile — Zipp's patented variable-depth rim shape that gives the 858 NSW its distinctive scalloped appearance. Along the inner diameter of the rim, a series of Hyperfoil nodes (fin-shaped structures integrated into the Sawtooth geometry) work in concert with HexFin ABLC dimples to control airflow around the wheel. The HexFin ABLC dimples are hexagonally shaped depressions arranged in fin-shaped clusters at each Hyperfoil. Their angular geometry increases boundary layer mixing, keeping airflow attached to the rim surface longer and reducing drag. Meanwhile, the Sawtooth undulations increase vortex shedding frequency — producing more, smaller, and more predictable vortices. The practical result is a wheel that holds a line in gusting crosswinds with significantly less rider input than a conventional constant-depth rim at the same depth. Zipp calls this AeroBalance: peak aerodynamic efficiency and genuine crosswind stability in the same wheel.

The 858 NSW is built on Zipp's TSE (Total System Efficiency) framework, which targets the four barriers to cycling speed — wind resistance, gravity, rolling resistance, and vibration losses — as an interconnected system. The hookless carbon rim construction addresses multiple barriers at once. Hookless rims are lighter than hooked alternatives and create a more seamless interface with tubeless tires, enabling lower pressures where tubeless compounds perform best. The 23mm internal rim width is optimized for 28–32mm tires, with Zipp citing 30mm as the aerodynamic and compliance sweet spot on this rim. Running a 30mm tubeless tire at lower pressure reduces rolling resistance, absorbs road vibration, and keeps the contact patch stable through corners — gains that accumulate meaningfully over a long race or triathlon run leg. Maximum recommended pressure is 73psi, keeping you in the range where the tire and rim combination works as designed.

The ZR1 SL hub runs custom hybrid ceramic bearings — ceramic rolling elements in steel races — for reduced friction and extended service life compared to full-steel alternatives. The center lock disc interface ships with the lockring included. Driver body options cover SRAM XDR for current 12-speed drivetrains and SRAM/Shimano Road (HG11) for 11-speed, making the 858 NSW compatible across the range of modern groupsets. Zipp's ImPress direct-print graphics apply branding without covering the HexFin ABLC dimples — a deliberate choice, since exposed dimples are required for the aerodynamic system to function. The 858 NSW carries a lifetime warranty.

Design Benefits

1. Sawtooth variable-depth rim profile simultaneously reduces aerodynamic drag and side force — addressing the fundamental crosswind stability tradeoff that limits conventional deep-section wheels.
2. Hyperfoil nodes and HexFin ABLC dimples manage boundary layer airflow and vortex shedding frequency, producing a deeply aero wheel that handles predictably in variable wind conditions.
3. Hookless tubeless construction with 23mm internal width enables lower pressures and wider tires, reducing rolling resistance and road vibration — the two speed barriers that most deep wheels leave unaddressed.
4. ZR1 SL ceramic bearings reduce rolling friction at the hub for a faster, more efficient drivetrain interface with a longer service interval than steel-bearing alternatives.
5. TSE framework treats wind resistance, gravity, rolling resistance, and vibration losses as a single system — so every design decision on the 858 NSW is evaluated against all four barriers, not just one.

Final Take

The 858 NSW rear wheel is built for riders who want no compromise at the deep end of the aero spectrum — triathletes and time trial specialists who need every aerodynamic advantage available, and road racers who can make use of an 85mm rim in races where conditions favor it. The Sawtooth geometry's crosswind stability makes the 858 NSW usable in conditions that would make a conventional 80mm rim a liability. Pair it with the 858 NSW front wheel for the full system, or run it where rear-wheel aero matters most.