In India, demand for three wheelers with low noise is increasing among the customers thereby the noise reduction of three wheelers is necessary. In order to overcome the demand in the market, manufactures are giving more importance to noise levels at passenger ear level and driver ear level. In test vehicle it was found that engine is the main noise source, biggest challenge was to reduce noise transfer from engine compartment to passenger and driver ear. In three wheelers it is more difficult as there is no close cabin.
This paper main objective is to reduce noise levels at driver and passenger ear level. The objective and subjective evaluations of both vehicles were carried out to identify the levels at driver ear level and passenger ear level. First task was to find out noise sources in engine. Most dominating noise source was tappet and flywheel area. Modifications were done on tappet cover and flywheel cover to reduce noise levels. Different techniques were used in this project like partial enclosure of engine, modifications in vehicle engine compartment. The result shows reduction in sound levels at passenger and driver ear level in modified vehicle comparing with old vehicle.