Cranks and bottom brackets have a decisive influence on the overall functional performance of a bicycle. Clean running, good power transmission and high load capacity are existential factors when choosing a crankset. Shimano manufactures a wide range of different cranksets and matching bottom brackets. This means that an optimally suitable system is available for every bicycle and every discipline. Hollowtech II works with 24 mm axles and bearings. After analysing all factors and carrying out tests, they decided on axles and bearings with a diameter of 24 mm. This offers the best possible balance of rotational efficiency, stiffness, load capacity, tightness and weight in proven Shimano quality.
Octalink eightfold toothing of bottom bracket axle and crank. Optimised intervention, more efficient power transfer. The hollow axle significantly increases the rigidity of the bearing. Inclined ribs ensure a permanently loadable connection between the inner bearing axle and crank.