R45 Road Racing HubsShimano and SRAM Compatible rear hubThe R45 hubset is 20% lighter than our Classic hubset. We designed sleek new hubshell bodies and new 17 mm axles. That’s 17 mm from dropout to dropout resisting deflection during cornering or when the power is full on. We designed a driveshell with a twin bearing design that responsibly removed as much weight as we could from the inner components. Even our patented RingDrive engagement system was redeveloped resulting in a quiet, fast-engaging 45-tooth stainless steel system unique to the R45 rear hub. Fast We designed and built a bearing specifically for the R45 hubset. As with every King bearing, these stainless steel sealed bearings are made in-house in Portland, Oregon and individually hand-checked for precision and smoothness. Our proprietary bearing design allows us to place more rolling elements per bearing meaning greater durability and precision. R45 bearings also feature lightweight, low-friction seals for fast rolling and can be easily serviced at regular intervals using only a single 2.5 mm hex wrench and penknife.