The noise output of a 750 cc motorcycle was reduced from 98 db(a) to 86 db(a) under current European test conditions, without significant power loss. Principal noise sources were exhaust, induction, and mechanical noise, with induction noise being higher than expected, and the untreated mechanical noise mainly responsible for the final level settling no lower than 86 db(a). Induction noise was reduced by 12 db(a) by using a damped cavity side-resonator, and exhaust noise by 20 db(a) (compared with standard silencer equipment) by using a new silencing principle. Both intake and exhaust silencers were inexpensive to produce of compact dimensions, and presented no special manufacturing problems. (A) /TRRL/

  • Availability:
  • Corporate Authors:

    Academic Press Incorporated

    Berkeley Square House, Berkeley Square
    London W1,   England 
  • Authors:
    • Roe, G E
  • Publication Date: 1974-3-8

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Filing Info

  • Accession Number: 00128133
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Apr 21 1976 12:00AM