Sound - Design for Motorcycles Influence of Different Parameters on the Sound

Beside performance, handling and styling the sound characteristic of a motorcycle is a very important feature for the acceptance of the product by the customers and therefore the commercial success of a new product. Creating a special brand sound becomes more and more important to create a product that can be easily distinguished from competitor products and is therefore considered to be something special. On the other hand the legal limits in terms of pass - by noise allow for a very little margin for the creation of a special sound.

During the product sound design phase the different perceptions of the rider wearing a helmet and pedestrians have to be considered. In passenger cars sound design has been known for a long time and the creation of a special sound for the driver inside the passenger compartment can be achieved with little influence on the exterior noise and therefore on the noise which is limited by legislation. On a motorcycle the creation of a special noise impression for the rider is much more dependant on the margin given by the law due to the lack of an enclosed passenger compartment. For the creation of a special brand sound for motorcycles, within the specified legal limits, all noise sources of the engine, intake and exhaust system have to be taken into consideration. This paper gives an overview of the current legislation and also an outlook on possible future regulations and their influence on technologies that are currently used for noise control on motorcycles. Furthermore the relevant noise sources of the engine, intake and exhaust system and the related parameters and their influence on the noise perception are discussed.

Following the approach to create a special brand sound is described here within. This paper covers benchmark measurements and the definition of a target sound, the identification of the relevant noise sources and parameters plus the definition of noise relevant design features supported by simulation.