Based on the outcomes of a European Commission study, proposal to clarify the text and align its provisions with other vehicle sound regulations, especially UN R41, including to replace references to “two wheeled moped” with the term “L1 category vehicles” (and consequently to replace references to “moped” with “vehicle”) and to replace the term “noise” with “sound” (except for references to background noise) throughout the regulation. It proposes improved terminology and definitions, including new ones, improved sound emission testing conditions and procedures. It also introduces sound emission measurement through new testing of in use vehicles in motion.

Proposal to clarify the text of the regulation, update provisions in line with Supplement 1 to the 02 series of amendments (WP.29/2015/64), and to align its provisions with those of UN R41 and R51, including:

1. replace the term “two wheeled moped” with “L₁ category vehicle”;
2. replace the term “moped” with “vehicle”;
3. replace the term “noise” by “sound” except for its use related to background noise;
4. replace “noise made by” with “sound emitted by”;
5. specify in each use of the term “speed” whether the reference is to engine speed or vehicle speed;
6. add definition for “rated engine speed” in addition to “rated maximum net power”;
7. add definitions for “reference mass” and “test mass”;
8. add definition for “maximum vehicle speed”;
9. add the words “or electronically” and “rider selectable” to paragraph 6.3.2. to cover electronically adjustable exhaust or silencing systems;
10. allow the use of in-motion testing in addition to stationary testing in Annex 1 and add the necessary data reporting provisions in Annex 3 similar to provisions under UN R41 04 series;
11. update references to ISO standards; and
12. add sub-paragraphs to Annex 3, paragraph 5.2. to hinder tampering.

Status report on the European Commission program to investigate the potential for new sound limits of L-category vehicles at Euro 5 step and make a justified proposal.

Additional materials covering task force topics and possible time frame for EC proposal on Euro 5 sound limits.

Proposal to exclude pure electric vehicles, including vehicles with auxiliary electric propulsion, from the scope of the regulation. This proposal has been submitted to complement WP.29/2017/4.

Discussion of motorcycle and related vehicle noise issues, especially related to aftermarket modification (non-original replacement exhaust silencer systems (NORESS)).

Presentation on the status of the European Commission-sponsored study to investigate the potential of and develop a proposal for new sound limits of L-category vehicles under Euro 5.

German authorities have carried out a study to assess the possibility for measuring UN R41.04-approved L category vehicles using typical “roadside check” equipment. The study found that such equipment provides a “lite” version of the UN 41.04 procedures that is useful in evaluating real-world performance. Germany intends to pursue a national “pass-by lite” test directive for UN R41-approved motorbikes and for non-original replacement exhaust silencer systems (NORESS) roadside and periodic technical inspections.

Proposal to exclude pure electric vehicles, including vehicles with auxiliary electric propulsion, from the scope of the regulation, to include sound-level measurement conditions for powered cycles equipped with compressed air engine and to introduce sound-level limits for powered cycles.