GAR | WP.29/2026/143

WP.29/2026/143

UN R117: Proposal for a Supplement 4 to the 04 series of amendments

Source(s)

GRBP

Date

9 Apr 2026

Status

Formal WP.29 review

Subject

UN R117 Tire Noise, Wet Adhesion, and Rolling Resistance

Impact

04 series of amendments | Supplement 4

Meeting(s)

WP.29 | Session 199 | 22-26 Jun

Agenda item 4.8.8. Proposal for Supplement 4 to the 04 series of amendments to UN Regulation No. 117 (Tyres, rolling resistance, rolling noise and wet grip)

Proposal to delete Table of contents, Annex 10 and all its appendices, amend para. 1.1. to clarify application to new pneumatic tyres of classes C1, C2 and C3 in new state regarding sound emissions and rolling resistance and in new and worn state regarding wet adhesion, delete para. 1.3., amend para. 2.18. to specify reference tyres F2872-25, F2871-25, F3678-25 and F3677-23, delete para. 2.21., delete para. 3.1.1.1., amend para. 3.2.1. to describe major features and their effects on tyre performance, delete paras. 5.7. to 5.10., delete Annex 1 items 8.6. and 8.6.1., amend Annex 5 part (b) para. 1.1.1. to establish surface friction values by trailer or vehicle method according to tyre class and SRTT, amend Annex 5 part (b) para. 1.1.1.1. regarding coefficient of variation and peak braking force coefficient, and delete Annex 10. Document based on GRBP/2025/28, GRBP-82-27, GRBP/2026/6, GRBP-83-20-Rev.2 and GRBP-83-48-Rev.1.

Downloads

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Related documents

Excerpts from session reports

GRBP | Session 82 | 3-5 Sep 2025

13. The expert from ETRTO proposed a correction to the 04 series of amendments to UN Regulation No. 117 (GRBP-82-27). GRBP adopted the proposal but agreed not to submit it immediately to WP.29 and AC.1, awaiting other amendment proposals to the same series of amendments.

16. The Co-Chairs of TF TA presented their proposals for a new UN Regulation on tyre abrasion, together with the corresponding amendments to UN Regulation No. 117 (ECE/TRANS/WP.29/GRBP/2025/27 as amended by GRBP-82-29 and ECE/TRANS/WP.29/GRBP/2025/28). GRBP noted that both ‘indoor drum’ and ‘on-road vehicle’ test methods were included on equal footing in the draft new UN Regulation, but a low level of correlation between the methods had been observed from the market assessment data, with much better results from the dedicated correlation-validation (COVA) testing campaign. GRBP also noted that the limit values for tyre abrasion remained to be determined for both Stages 1 and 2.

17. The expert of ETRTO highlighted the position of the EU tyre industry on setting the abrasion limits (GRBP-82-24, GRBP-82-25) and proposed modifications to the TF TA package of amendments (GRBP-82-37).

18. Several experts expressed the view that the drum method was not yet ready for adoption, given a low reproducibility of results in different laboratories and the need for further validation. They suggested to start first with the on-road method and add the drum method at a later stage. Some other experts were in favour of including both methods in the new Regulation from the beginning. Following an in-depth discussion on the methods and tyre abrasion limits, GRBP realized that it would not be possible to reach a consensus at this session and agreed to finalize the amendment package at the next meeting. GRBP invited experts from all Contracting Parties to actively participate in the coming TF-TA meetings to contribute to reaching a compromise at the next session.

19. The expert from India suggested to explicitly indicate that the draft new UN Regulation would apply to radial tyres only and not to bias-ply tyres.