JASIC presentation in support of Japanese positions for the 03 series of the UN regulation on vehicle noise (UN R51). The presentation addresses a three-stage, six-year transition to more stringent noise limitations and proposes additional vehicle subcategories.

Updated JASIC presentation in support of Japanese positions for the 03 series of the UN regulation on vehicle noise (UN R51). The presentation addresses a three-stage, six-year transition to more stringent noise limitations and proposes additional vehicle subcategories.

Updated proposal from Japan concerning new noise limit values for light vehicles, including low-powered and “mini” cars and trucks, under UN R51.

Japanese explanation for placing Stage 3 limit values in brackets (signifying tentative proposals subject to further consideration) because of the contradiction between measures to reduce automotive noise and technical measures to meet the aims of fuel consumption/CO2 regulations.

Presentation in support of Japan’s noise limit values proposal (document GRB/2012/7).

Presentation in support of document GRB-58-06 proposing amendments to UN R51 with regard to the categorization of flat-front light (kei) commercial vehicles.

Presentation in support of the proposal for additional vehicle categories and sound emission level requirements under UN R51. A “Flat Front Light N1 Vehicle” is defined as:

• GVM ≤ 2.5 ton
• PMR (power to mass ratio) of GVM ≤ 35kW/t
• Engine capacity ≤ 660cc
• d value<1,100mm

Presentation of Japan’s plans for phasing in UN R41, UN R51 (Phase 2, but not Phase 3 limits), and UN R117 requirements.

Presentation concerning vehicle noise relationship to speed and acceleration and other factors

Japan presentation on tests conducted and questions raised.

In vehicles with automatic transmissions, upshifts during testing cause SEM expected values to be exceeded. The proposal addresses three cases: vehicles with non-locked gear ratios, vehicles with locked gear ratios, and vehicles with only one gear ratio. For Case 1, such data does not meet conditions in R51-03 Annex 9 “4.5.2. Non-locked transmissions” and require no SEM correction. For Case 2, the proposal adds text to Annex 9 (7), Appendix 1, paragraphs 3.4. and 3.5., permitting substitution of maximum engine speed nMAX(AA-BB)TEST for nBBTEST when the maximum engine speed between AA’ and BB’ exceeds the engine speed at BB’.

Current RD-ASEP derives the regulatory level based on the certified value without accounting for margin against regulatory values of the certified value. RD-ASEP additionally regulates partial acceleration, unlike current ASEP which only stipulates full-throttle acceleration. It is proposed that RD-ASEP should take into account a margin against the regulatory values of the certification values, similar to current ASEP, to prevent quiet vehicles such as BEVs from being unfairly deemed NG.