Ensure steering stability by reducing kickbacks at high speeds, while maintaining light-effort handling at low speeds… To satisfy these two contradicting requirements, the development engineers at Honda’s Asaka R&D analyzed in depth the motorcycle handling characteristics and the front end shake triggered by a kickback from the road. The target set at the end of the painstaking researches was the development of an unprecedented steering damper having the damping force variable depending on the running conditions.
Key points of development
During the HESD development, elaborate analyses were exercised especially on the front end shake caused by kickback from the road. Such front end shake is one of the vibration phenomena (vehicle body behavior) during high speed running. Using the large-displacement, super-sport-type model, actual running tests were repeated to set targets for the minimum damping force for light-effort handling and the maximum damping force to reduce front end shake induced by kickback from the road. It has been revealed that the damping characteristics have to be altered depending on the speed and the acceleration to constantly maintain an optimum damping force under various running conditions.
Based on the above-mentioned findings and deriving from the rotary-type steering damper technology applied to the MotoGP machine RC211V, the world’s first, variable damping-type rotary steering damper “HESD”, that alters the flow resistance in the hydraulic damper by an electronic control system depending on the running conditions, has been developed to realize a steering damper having ideal damping characteristics.
HESD
Applied to CBR1000RR
The front end shake when passing on an uneven road surface is the cause of rider discomfort and fatigue. The super-sport motorcycle CBR1000RR, which inherits the DNA of the MotoGP machine RC211V, has been chosen as the first motorcycle to apply the world’s first HESD. With the HESD employed, the CBR1000RR offers to the rider both the sure-footed feeling in high-speed running including the situation on a race track and the light-effort handling at low speeds, thus satisfying rider demands.
