Under the current 04 series of amendments to UN Regulation No. 41, the engine speed should be measured during all tests in Annex 3 and Annex 7 (Additional sound emission provisions – ASEP). However, IMMA has found that there is very little difference between the measured and the calculated engine speed for a manual transmission (MT) vehicle (Annex, figure 1) and no impact on the test result (Annex, figure 2). Therefore, this proposal would introduce a calculated engine speed for MT vehicles and for continuously variable transmission (CVT)/automatic transmission (AT) with locked gear mechanism into UN Regulation No. 41.

Correction to the text of the proposed amendment to introduce a calculated engine speed for manual transmission vehicles and for continuously variable transmission (CVT)/automatic transmission (AT) with locked gear mechanism into UN Regulation No. 41.

Correction of typographical errors in the original proposal (document GRB/2015/2): “locked” instead of “rocked”.

In response to concerns that approval agencies may not grant manufacturers the additional 1dB for L(wot) on conformity of production tests as changes had been made to Annex 6 of R41-04, GRB issued an interpretation recorded in the report of its 56th session. However, IMMA believes that industry and agency personnel may still not be aware of the interpretation. Therefore, IMMA proposes to codify the interpretation within UN R41.