Although legislation and type approval of L-category vehicles (LV) mainly cover average driving conditions, much of the local environmental impact is caused by specific conditions at which the highest noise levels and emissions occur. Considering the need to reduce noise and pollutant emissions of LVsin real world situations, an assessment is required to identify critical driving conditions under which high noise and emissions occur. In the LENS project, an investigation has been made into the driving conditions of LVs that are relevant for high noise and pollutant emission events. Therefore, LENS published its latest deliverable ‘driving conditions and requirements for a test programme based on real world evidence of LVs operation‘, which focuses on:
- A review of existing knowledge from previous projects, World Motorcycle Test Cycle (WMTC) development, original equipment manufacturer (OEM) data, public domain) on real world driving conditions
- Identification of LV operation and critical driving conditions for noise and exhaust emissions,targeted roadside/on board measurements to validate preliminary findings on critical cases
- An assessment to what extent current type approval regulations cover real world driving conditions
- Recommendations for the LENS measurement campaign on 150 vehicles including on-road, laboratory, test track, and roadside measurements.
Considering the findings in the literature and the data analysis, and the evidence of the relevance of conditions critical for high noise and emission levels, it is recommended to include these in the LENS test programme for both noise and pollutant emissions:
- Cold start (mainly for emissions)
- Rpm burst (engine revving)
- Acceleration from standstill in first and second gear, loaded + unloaded
- Max rpm pass-by especially for mopeds, scooters and sports motorcycles
- Transition from constant speed or acceleration phases to deceleration phases
- ‘Max’ acceleration (or best achievable) from standstill in first and second gear
- Acceleration at speed, from 50 to 100 kmh
- Rpm fluctuation (intermittent revving)
- Use in-service vehicles from the market for the test programme, with a minimum mileage of 3000km