Motorcycle Noise Annoyance in Residential Areas Along Popular Leisure Routes.

Motorcycle noise along leisure routes constitutes a distinct environmental health burden poorly captured by standard road traffic noise indicators. This study derives source-specific exposure-response functions and examines non-acoustic predictors of residential motorcycle noise annoyance. A mixed-methods socio-acoustic design was applied in five study areas in Baden-Wuerttemberg, Germany. A community survey (N = 493) assessed long-term annoyance (12-month recall); a smartphone-based experience-sampling study (MotoApp; N = 213; ten days in summer 2022) collected hourly ratings. Acoustic measurements provided vehicle-specific LAeq,1h, LAFmax,1h, and N60; exposure-response functions were estimated using logistic regression and generalised estimating equations. In the long-term survey, 46.5% were highly annoyed by motorcycle noise, compared with 18.4% for passenger cars. Motorcycle exposure-response curves were markedly shifted; the 25-highly-annoyed threshold was reached approximately 16 dB lower in LAeq,1h than for passenger cars on weekends. Negative attitudes towards motorcycle riders, low coping capacity, and noise sensitivity were significant independent predictors. Source-specific assessment is necessary for motorcycle leisure routes. The 25-highly-annoyed criterion maps to approximately 52 dB LAeq,1h and 78 dB LAFmax,1h on weekends, and to 25 N60 events per hour-substantially below current road traffic guideline values-providing actionable thresholds for noise action planning.