Eliminating Cardan Torques in Motorcycles

In addition to their well-known advantages, motorcycles with cardan drive systems also have certain disadvantages, such as the large mass of the final drive, which has a negative effect on the suspension.

Furthermore, when a cardan shaft is angled, it always runs unevenly and reduces torque. The necessary sliding sleeve on the cardan shaft, which moves with every suspension compression due to changes in length, also dissipates torque.

We solve these issues by simply fixing the entire drivetrain in place so that the cardan shaft is aligned with the transmission output shaft and the ring gear; a universal joint and sliding sleeve are therefore unnecessary.

The damping works by mounting a swing arm bearing near the center of gravity, on which the entire drivetrain oscillates. Due to the lever effects with near-equal force balance between the engine and final drive, little weight is placed on the rear wheel, allowing the damping to respond very sensitively; furthermore, a very large suspension travel is possible without the drivetrain affecting the suspension.

The immense effort required to provide torque support against the up-and-down oscillation of the rear end is no longer necessary.

A distinctive feature of the design is that the engine also oscillates slightly; furthermore, the connection between the shift lever on the transmission and the foot-operated shift lever must be flexible.