The behavior of a bicycle under pedaling forces is not linear but rather asymmetrical.
This is due in most part to pedal forces being applied evenly on both right and left sides (assuming an athlete has a normal and efficient pedal stroke) although the force generated by both right and left is transferred only to the right side of the frame as the chain is located only on the drive side. During part of the pedal stroke forces applied to the bike are opposing and during the other part they are transferred. This, in addition to asymmetric forces being applied to the handlebars as the athlete pushes and pulls even lightly during normal pedaling, creates an input that is not efficient and linear. In other words, pedal forces applied to a symmetric frame can only give an asymmetric and less efficient output.
This phenomenon is easily verified and can be visible almost to the naked eye. At Cicli Pinarello all new projects are validated first and foremost by theoretical studies using FEM (Finite Element Method) analysis. Upon completion of these theoretical calculations all results are then verified in the laboratory. In both theoretical calculations as well as laboratory studies, the asymmetric behavior of a symmetric frame is evident. The frame can flex up to nearly 5mm on one side and only 1-2 on the other.
This can only be contrasted by an asymmetric frame construction. On one side the frame is perhaps too rigid in which case some material can be removed. On the other side the frame is too flexible and needs to be reinforced or made more rigid. Working with carbon fiber the task of increasing rigidity and flexibility in determined areas is facilitated with the type of carbon, quantity of material, direction of the fibers and shape of the frame all can be changed to achieve the desired result. Design of an efficient frame, with asymmetry in both form and construction is possible through a long process of advanced analysis, using the latest technological software.