Working Party on Noise | Session 62 | 1-3 Sep 2015

12. The expert from the Netherlands presented a study (GRB-62-09 and Add.1) on noise emission from the Original Equipment Manufacturer (OEM) tyres of a specific size which were found to be around 1 dB(A) lower than the one from replacement tyres of the same size. The expert, thus, proposed to further reduce the limit values for OEM tyres in the 02 series of amendments to Regulation No. 117 (GRB-62-11 and Add.1).

13. The expert from Switzerland expressed his support for the general direction of the Dutch proposal. The experts from Germany and EC were of the view that, at this stage, it would be premature to tighten the tyre noise limits of Regulation No. 117. The expert from France called for a holistic approach to this issue. The experts from ETRTO and OICA expressed doubts about the representativeness of the tyre sample used in the Dutch study. The expert from ETRTO also delivered comments on the proposal for amendments to Regulation No. 117 (GRB-62-17). Finally, GRB invited all experts to further study the Dutch proposal and decided to revert to this issue at the next session.

Working Party on Noise | Session 66 | 4-6 Sep 2017

15. The expert from the Netherlands provided an overview of their research projects on tyres and proposed a two-stage tightening of the tyre limits for the rolling resistance coefficient, wet grip index and rolling sound emissions (GRB-66-01 and Add.1, GRB-66-03). He also highlighted the importance of keeping the correct tyre pressure for fuel efficiency and pointed out shortcomings of the EU system for labelling tyres.

16. The expert from ETRTO was of the view that the selections of tyres in the Dutch studies was not representative enough for the European market and volunteered to submit to the next GRB session a more comprehensive analysis. The expert from OICA supported the ETRTO view and proposal. He further introduced the results of a recent study of C1 summer tyres (GRB-66-22) according to which no tyre was performing equally well in rolling sound and handling. The expert from Germany acknowledged the progress achieved in rolling sound and pointed out the need to find a compromise for the three tyre parameters in question. He also agreed that the tyre labelling system would need to be improved.

17. The Chair was of the view that amending the limit values in Regulation No. 117 would first require a general agreement of all stakeholders, including the Working Party on Brakes and Running Gear (GRRF). Finally, GRB decided to continue the discussion at the next session.

Documentation
GRB-66-03 | Proposal for amendments to the 02 series of amendments to Regulation No. 117 (Netherlands)
GRB-67-08 | UN R117: Assessment of the Netherlands proposal (ETRTO)
GRB-68-02 | UN R51.03: Comments on tyre selection (China and CATARC)
GRB-68-19 | UN R117: Proposal for a Supplement to the 02 series of amendments (Russia)
GRB-68-23 | Snow tyres provisions: status report (BIPAVER, ETRTO, Finland, France, Germany, Russia, and Japan)
GRB-68-27 | Strengthening tyre limits: new developments (Netherlands)
GRVA/2018/5 | UN R117: Proposal for a Supplement (ETRTO)