UN R117: Proposal for the 04 series of amendments
Document WP.29/2023/8
19 December 2022

Proposal to revise the limits for rolling resistance and wet grip, to address tyres for vintage vehicles, to revise the definition for special-use C1 tyres, and to set the wet grip index threshold at 0.80 for class C1 tyres with a nominal aspect ratio equal to or less than 40, a section width equal to or higher than 235 mm and suitable for speeds equal to or greater than 300 km/h and for class C1 all terrain and special use tyres. The proposal also introduces the kworn factor in a new para. 3 in Annex 9 to address wet grip of C2 and C3 tyres in a worn state (see GRBP-75-26-Rev.1 for concept), provisions to allow the type approval of special use tyres that fulfil the requirements for snow performance as laid out in Annex 7, and a new definition of traction elements to characterize traction tyres.

Status: Adopted by WP.29
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Previous Documents, Discussions, and Outcomes
4.6.7. | Proposal for the 04 series of amendments to UN Regulation No. 117 (Tyre rolling resistance, rolling noise and wet grip)
4. (c) | UN Regulation No. 117 (Tyre rolling resistance, rolling noise and wet grip)

16. The experts from the European Commission introduced a new 04 series of amendments to UN Regulation No. 117 (ECE/TRANS/WP.29/GRBP/2022/12). The expert from ETRTO proposed further modifications (GRBP-76-23 and GRBP-76-32). GRBP adopted ECE/TRANS/WP.29/GRBP/2022/12, as amended by GRBP-76-23 and GRBP-76-32, subject to the removal of the square brackets, and requested the secretariat to submit it for consideration and vote at the March 2023 sessions of WP.29 and AC.1 as the draft new 04 series of amendments to UN Regulation No. 117.

20. The expert of IWG WGWT presented their proposals for the moulded standard reference test tyre and wet grip of C2, C3, and some clusters of C1 tyres in a worn state (ECE/TRANS/WP.29/GRBP/2022/22, ECE/TRANS/WP.29/GRBP/2022/23, GRBP-76-02 and GRBP-76-05). The expert from ETRTO introduced additional amendments (GRBP-76-24-Rev.1, GRBP-76-33-Rev.1 and GRBP-76-34).

21. GRBP adopted ECE/TRANS/WP.29/GRBP/2022/22, as amended by GRBP-76-05 and GRBP-76-34, subject to the removal of the square brackets, and requested the secretariat to submit it for consideration and vote at the March 2023 sessions of WP.29 and AC.1 as draft Supplement 1 to the 03 series of amendments to UN Regulation No. 117.

22. GRBP adopted ECE/TRANS/WP.29/GRBP/2022/23, as amended by GRBP-76-02, GRBP-76-33-Rev.1, and GRBP-76-24-Rev.1, and requested the secretariat to submit it for consideration and vote at the March 2023 sessions of WP.29 and AC.1 as part of the draft new 04 series of amendments to UN Regulation No. 117.

23. The expert from ETRTO introduced an amendment proposal on a “traction tyre” (ECE/TRANS/WP.29/GRBP/2022/17). GRBP adopted the proposal, as amended by GRBP-76-31, and requested the secretariat to submit it for consideration and vote at the March 2023 sessions of WP.29 and AC.1 as part of the draft new 04 series of amendments to UN Regulation No. 117.

Related and Previous Documents
GRBP/2022/12
GRBP-76-23
GRBP-76-32
GRBP/2022/23
GRBP-76-02
GRBP-76-33/Rev 1
GRBP-76-24/Rev.1
GRBP/2022/17
Relates to UN R117 |