'Cross goes aero.
Though it does in fact have "aero" in the title, the key feature of Rotor's QCX1 Aero Chainring is actually its more pronounced oval shape, up to 12.5% from the road-specific version's 10% ovality. That means it's even more efficient than the standard road model, especially in the high-reward portions of the pedal stroke where you're actually turning over the crank—not a bad upgrade considering this is Rotor's first foray into one-by 'cross machines. Efficiency at this portion of the stroke is arguably more valuable in 'cross, as punching out of corners and spinning up to speed after run-ups and obstacles can be the difference between getting a gap or just getting gapped.
The alternating tooth profile helps retain the chain on a one-by drivetrain, and deep chamfers encourage peanut butter muck to stay the hell out of your drivetrain. Rotor recommends running the QCX1 ring on the inner position of a double crankset, but the brand does also offer cranksets and spider adapters to reposition the ring.
- An oval chainring for one-by cyclocross bikes
- Oval ring shape increases the sweet spot of the pedal stroke
- 12.5% ovality is more efficient than Rotor's standard
- Tooth profile built to retain chain and clear muck
- Rotor recommends running as the inner ring on a double crankset