Dynamic Balance Unlike carbon rims, all the aluminium rims are joined. The joint, though indispensable, entails a concentration of material in a single point and creates an annoying “jump†effect at speed. Fulcrum has eliminated this annoying problem with the Dynamic Balance patent. The concept is simple and elegant: balance the mass of the joint with a mass of the same weight. For top models, this is obtained by a special operation on the section of the rim opposite the rim joint. For entry-level models, Dynamic Balance is obtained by using two oversized spokes in the section opposite the joint. The result is a wheel with perfectly balanced rotational dynamics.