Proposal from the Worn Tyres working group to amend their earlier formal submission.

Proposal from the Worn Tyres working group to amend its previous formal proposal.

Report on discussions concerning the definition of a specific cluster ‘tyre 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’ by indicating the intended use of such tyres.

Presentation on the Strengthening the Effect of quieter tyres on European Roads (STEER) project.

Proposal for a reference document.

Proposal to introduce provisions to allow the type approval of special use tyres that fulfil the requirements for snow performance as laid out in Annex 7. The respective marking related to the “Alpine” symbol has been considered for those tyres complying with these requirements.

Proposal to introduce provisions to allow type approval of special use tyres that fulfil the requirements for snow performance as laid out in Annex 7. The respective marking related to the “Alpine” symbol has been considered for tyres complying with these requirements.

Proposal to correct editorial mistakes in document GRBP/2021/17 that were not corrected by informal document GRBP74-31-Rev.1.

Proposal to introduce a new definition of traction elements to characterize traction tyres.

Proposal from the Worn Tyres working group 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 (see GRBP-75-27, slide 6). The proposal also introduces the k_worn 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).

Proposal from the Worn Tyres working group to improve precision of the test procedures for measuring the wet adhesion of tyres in a worn state by using a moulded SRTT16 reference tyre (instead of a buffed tyre), to introduce new transitional provisions related to this change, to extend corrections already made to thee 02 series to the 03 series and make additional editorial corrections, and to define the range for tyre inflation vis-à-vis rim size to reduce uncertainties in measuring tread depth.

Proposal to bring the latest ISO 10844 standard test surface into the Regulation.

Proposal to revise the limits for rolling resistance and wet grip, address tyres for vintage vehicles, and revise the definition for special-use C1 tyres.