Carbon spokes are the headline: Shimano finally adopts what Zipp and others have run for years, and it drops enough weight to let the rim, hub and spokes get co-engineered as one system under the "Science of Speed" label. The gains are real but not radical — 6% aero after 5.4 million simulations, 2.7W saved at race speed — the kind of incremental engineering that doesn't need a saw-tooth rim to sell itself. Shimano kept the classic profile while Zipp and Scope chase textured surfaces, betting the spec sheet does the talking. Ships September 2026.