Presentation of fka’s tyre technology division capabilities in testing, simulation and research. Describes fka’s collaboration with ZF on developing a C3 tread wear drum test rig to be operational in Q1 2027. Outlines fka’s offer to support joint development and validation of C3 drum abrasion methodology with TFTA members, requiring funding commitments or test workload from interested partners. Discusses technical considerations including drum curvature effects, surface texture replication, testing capacity estimates, and environmental impact of convoy versus laboratory testing methods.

ETRTO analysis of the European C3 tyre market segmentation, emission levels per tyre segment, and vehicle configurations. ETRTO recommends focusing on Segment A (Heavy Duty Tyres 22.5 for Long haul and regional usage), which captures approximately 71% of wear emissions. ETRTO evaluated five alternative methods to the convoy method using criteria including time to market, representativeness, regulatory suitability, and cost. ETRTO concludes the convoy method focusing on Segment A is the only feasible method given the mandated timeline, despite drawbacks including test duration and environmental impact.

Discussion document presenting general considerations for a C3 tyre abrasion test method. Topics addressed include objectives for reducing C3 tyre wear, quantification of C3 abrasion relative to overall and C1 abrasion, C3 tyre life including retreading effects, operational factors influencing tyre wear such as fleet optimization and load management, and environmental concerns regarding C3 microplastics and chemical requirements.

Presentation on single-wheel trailer technology for measuring tyre wear on C1, C2, and C3 tyres. The document describes a narrow trailer with one measuring wheel that eliminates vehicle-specific influences such as axle geometry, suspension kinematics, and drivetrain concepts to enable direct comparison of tyres from different manufacturers. The trailer uses a Cardan joint coupling that transmits roll movement from the towing vehicle while allowing pitch and yaw movements, with adjustable ballast positioning to control wheel load. Comparison tables show that the single-wheel trailer method produces results similar to outdoor convoy testing for lateral force, braking force, and camber while avoiding wheel load transfer effects present in conventional vehicle testing.

Document presents Japan’s heavy-duty vehicle market structure, C3 tyre classification and market share, and proposes concepts for vehicle and indoor drum test methods for C3 tyre abrasion testing. The vehicle test concept recommends establishing a single test method based on typical operating conditions using the WHVC mode, with the drive axle as reference. The indoor drum test method is proposed as preferable due to higher test accuracy and lower environmental impact compared to vehicle testing. Test conditions under consideration include input conditions based on WHVC with curve and slope running modes, inflation pressure and load aligned with vehicle specifications, drum diameter potentially increased from 3 m, and drum surface conditions based on C1 tyre definitions.

Draft agenda for the 52nd session of TFTA on 8 and 9 October 2026 in Brussels and remotely. The main target of the meeting is brainstorming on C3 test method. Discussion items include framing the C3 challenge, C3 tyre segmentation to categorise diverse tyre groups and duty cycles into manageable regulatory groups, methodological ideation for simplified C3 testing approaches, and funding and resource allocation. Additional items include C1 outcome discussion with Korean test centers regarding circuit SRTT abrasion level range and C2 status on ongoing test campaign.

Updates the year reference to the latest international standard specifications

A two-day brainstorming session will be held in Brussels during October 8-9, 2026. The session aims to address the lack of a concrete test method solution for C3 tyre abrasion by reflecting on innovative test method ideas not bound to existing C1 and C2 approaches, brainstorming phased introduction of tyre abrasion requirements across C3 tyre segments, and optimising resources to reduce testing burden. Day 1 will address C3 market complexities and tyre segmentation across duty cycles; Day 2 will cover methodological ideation, funding and resource allocation, and review of the C2 test campaign before the February 2027 working document.

The Task Force on Tyre Abrasion completed work on the UN Regulation on tyre abrasion for C1 tyres and is launching C2 work. UN R186 on tyre abrasion for C1 tyres was adopted at WP.29’s 199th session in June 2026, with a two-stage implementation approach beginning 30 June 2028. C2 test method development is ongoing with an Informal Document to be submitted to GRBP in February 2027 instead of September 2026. C3 tyres will undergo a brainstorming session in October 2026 before commencing testing.

Current work involves data-collection preparations for TAPP data assessment using an updated template. Some testing has already begun.

The agenda includes discussion of the status of the 2026 workplan (TA-51-03), UTAC tyre abrasion timeline Gantt chart (TA-51-02), development of mileage potential metric and tread depth measurement prescription (TA-51-5), test method development status, preparation of TFTA status report for GRBP 84th session (TA-51-04), and next meeting(s).

The document presents reflections on equivalence criteria for C2 tyres under Annex 4. C1 and C2 protocols are expected to remain very similar, with most changes having no impact on ALI and facility correlation. Key differences include tyre load and inflation pressure specifications. The main hypothesis states that if final C2 methods remain closely aligned to C1 methods, the existing equivalence framework for C1 could be maintained and extended to C2 testing, with already equivalent facilities receiving automatic equivalence or minor validation, and new facilities requiring amendment of Annex 4 to accept a mix of C1 and C2 tyres for demonstration of equivalence.

The Tyre Abrasion Task Force has completed tyre selection for the Confirmation plan 2026 and informed candidate test facilities. Tyre availability and shipments remain ongoing. Data collection and compilation for data assessment awaits test commencement. The SWG on Data Assessment has agreed to transfer discussions regarding exclusion criterion for high variability tyres and acceleration corrections to TAPP upon its resumption of meetings.

Draft minutes of the 49th session of the Task Force on Tyre Abrasion (TFTA), held June 3rd, 2026 (9:00–12:00 CET). Previous meeting minutes were approved. Action item TA-48-1: ETRTO to check feasibility to upload acceleration calculation examples on TFTA wiki. ETRTO confirmed feasibility assessment completed; example files could be moved to TFTA wiki with a disclaimer that TFTA is not responsible for example content. Action item TA-49-1: ETRTO will prepare disclaimer to be reviewed and validated by TFTA during 50th session. Agenda adopted. ETRTO presented comments on updated Gantt prepared by UTAC per document TA-49-03. TFTA agreed to evaluate data analysis per tyre segment when data available. JASIC requested more time to review and provide feedback next session. ETRTO and JATMA tyre manufacturers ready to make selected tyres available; first orders and deliveries started last week of May. Training session on best practices organized 2nd half of June. Action item TA-48-2: SWG on data assessment to redefine scope and mandate. SWG leader presented amendment proposal per document TA-49-02. TFTA agreed with SWG scope and mandate per TA-49-02/Rev.1. ETRTO stated mileage potential work should address all TFTA members and tyre manufacturers associations at UN level. JRC studying tread depth divided by abrasion index approach. Topic readdressed next TFTA. ETRTO noted test campaign running; final results expected Q4 2026 including 2nd set Normal and 3PMSF temperature behavior tests and pressure impact test. Action item TA-49-2: EC and JRC will reflect by next TFTA session how annex 4 would be impacted considering C2 tyres. TFTA co-chair suggested extraordinary brainstorming session end September/beginning October 2026 for C3 tyre abrasion test method development. Next meetings: 50th session July 6 (9:00–12:00 CET); 51st session August 25 (9:00–12:00 CET).

Draft agenda of the 50th session of the Task Force on Tyre Abrasion, scheduled for July 6th, 2026 (9:00-12:00 CET). The session will address the status of the 2026 workplan, organizational matters, workplan updates, best practice meetings with test facilities, ITTAC proposal on tyre abrasion Convoy Method Dual-Normalisation Framework, UTAC tyre abrasion timeline, TFTA activities financing, development of the mileage potential metric, test method development status for C1, C2, and C3 tyres, preparation of supplement 1 to UN Regulation No. 186, and improvements to test methods.

The SWG on data assessment defines its scope as organisational matters for the Confirmation plan 2026, data anonymisation, governance and data storage to be defined. Its mandate includes preparation of tyre selection for the Confirmation plan, informing and collecting information from candidate test facilities, organizing tyre availability and shipments, and preparing data for TAPP data assessment including data collection and compilation.

The agenda includes status updates on the Convoy Method Dual-Normalisation Framework, tyre abrasion timeline, and test method development for mileage potential metric, tread depth measurement, and C3 tyre abrasion. Action items include ETRTO uploading acceleration calculation examples to the TFTA wiki, TFTA reviewing the Gantt chart, and the SWG on data assessment redefining its scope by the 49th session.

• ETRTO to check feasibility to upload acceleration calculation examples on TFTA wiki,
• SWG on data assessment to define scope and mandate by 49th session,
• ITTAC proposal (TA-45-8v1) on Convoy Method Dual-Normalisation Framework deferred to next session,
• UTAC Gantt timeline reviewed; ETRTO regulatory experts reviewed proposal; technical experts review pending,
• Tyres Europe stated EU Tire Industry funded over 3m for C1 activities and will provide over 1m additional financing for C2 and C3 work; requested TFTA co-financing,
• EC will escalate request; JRC will participate with 2 convoys for C2 in 2026 and C3 in 2027,
• SWG on data assessment to define scope, mandate, and leader for next session,
• DEKRA presentation on vehicle impact with SRTT; vehicle effect neutralized through tyre rotation for correlation purposes,
• JRC service life update presented; analysis planned for end of 2026,
• ETRTO C2 test method development restarted May 2026; temperature impact observed for winter SRTT requiring 2026 workplan verification,
• GRBP Working Document delivery for C2 test method postponed to February 2027,
• ETRTO and JASIC C3 presentations deferred for comments next session.

Existing C1 tyre-abrasion test methods cannot be directly applied to C3 tyres because vehicles equipped with C3 tyres are used differently. Japan is developing a vehicle test method using WHVC mode and plans to develop a drum test method based on test conditions and results. Test conditions will convert vehicle driving conditions representing the world into indoor drum test settings. C2 test method uses driving mode based on WLTP with fixed test load details, with verification tests using reference tyres. For C3, driving modes and test conditions are under preliminary investigation, with verification tests to be planned.

DEKRA Test Center examined whether vehicles fitted with SRTT impact tyre abrasion rates. Tests DEKRA #104 and DEKRA #41 compared SRTT Summer as candidate against SRTT Winter as reference, with abrasion indices of 1.18 and 1.19 respectively, showing no vehicle impact. Tests DEKRA 8 and DEKRA 9 showed abrasion rates of 45.1 mg/km/T and 45.0 mg/km/T respectively with no difference despite different vehicles. A 2024 convoy test with two Golf vehicles fitted with identical SRTT Summer showed a difference of 1 gram cumulated weight loss after 7,962 km (0.07 mg/km/T). DEKRA concludes the impact on abrasion level of the reference vehicle using SRTT is low or very low.

The document presents a European heavy-duty vehicle and tyre market overview and C3 test method development status. The C3 tyre market is complex and diversified, with applications including long haul, regional, on/off road, winter, and urban use. A test concept has been developed focusing on road usage with 22.5" tyres, using convoys of up to four vehicles with defined acceleration standards, road distribution of 60% motorway and 40% regional roads, and tests per axle comparing candidate tyres to reference tyres. Current activities include assessment of reference tyres strategy, temperature sensitivity evaluation, and confirmation of test parameters for heavy trucks in N₃/O₃ configuration, with tests reaching 30,000 to 45,000 kilometres.

TA-48-02 updates TA-47-02. C2 tyre abrasion rate index vehicle method uses a convoy of up to 4 vehicles with single tyres, GVW up to 3.5T, FWD, loaded 60%–74% of tyre nominal load with 50/50 front/rear distribution. Test distance is 10000 km at 80% nominal pressure. Reference tyres use 2 sets of test runs with C2 candidate SRTT and existing C1 SRTTs. 2025 testing in 235/65R16C and 205/65R16C sizes showed C2 tyres sensitivity to temperature similar to C1 tyres. 2026 plan repeats and extends 2025 testing to confirm reference tyres strategy, assess temperature sensitivity and pressure impact, and define validation plan.

ETRTO proposed three ways to estimate service life (TA-36-04): tread depth measurements, initial tread depth and abrasion index, and tread mass. JRC presented a service life index (TA-32-04) based on tread depth measurements and conducted a preliminary assessment of the second concept. Service life is estimated by linear extrapolation to 1.6 mm from tread measurements at test start and end. The Service life index is calculated as the ratio of candidate to reference tyre service life. Next steps include confirming the equation for service life via tyre characteristics and clarifying which tyre characteristics are needed.

The agenda includes discussion of status of the work plan 2026 including the ITTAC proposal on tyre abrasion Convoy Method -Dual-Normalisation Framework (TA-45-08/Rev.1) and UTAC Tyre abrasion timeline Gantt (TA-46-03/Rev.1), development of the C1 tyre mileage potential metric and tread depth measurement prescription, and test method development status under C2 and C3.

The 47th session of the Task Force on Tyre Abrasion convened on 2 April 2026. The review committee prepared final consolidation of a new UN Regulation on Tyre Abrasion for WP.29. TFTA reviewed the workplan including data assessment, tyre batch use, and equivalence assessment governance. For C2, ETRTO presented findings on the vehicle test method at 10,000 km, while JASIC reported on indoor drum test development. Discussion on C3 Heavy-Duty Vehicle tyre applications was deferred. The next session is scheduled for 11 May 2026.

Proposal for a new UN Regulation on the approval of new pneumatic tyres of class C₁ conforming to UN R117 with regard to their tyre abrasion performance, excluding temporary-use spare tyres, tyres with rim diameter ≤13 or ≥25, competition tyres, tyres for vehicles of categories other than M₁–M₃, N₁–N₃, O₁–O₄, ice grip tyres, studded tyres, speed category less than 120 km/h, special use tyres, and road legal race tyres. Abrasion index limits are 1.00 for normal and snow tyres, with adjustments for specific groups. Approval requires marking with approval reference number and suffix (A1 or A2). Testing uses either vehicle test method on public open roads (~8000 km) or indoor drum test method (5044 km), with test facilities demonstrating equivalence per Annex 4. From 1 July 2028, stage 1 approvals required for new types; from 30 June 2030, all types. From 1 July 2033, stage 2 approvals required for new types; from 30 June 2035, all types. Until 1 July 2028, test results from tests performed

This status report documents the Tyre Abrasion Task Force’s progress toward finalizing a draft UN Regulation on tyre abrasion for C1 tyres, as presented to GRBP 83 Part II. The task force pursued three workstreams: data analysis to reduce method uncertainty and inversion risk, editorial improvements to increase clarity of the draft regulation, and development of a method equivalence solution. GRBP 83 Part I achieved consensus on limit values and introductory dates but could not reach consensus on equivalence procedures between convoy and drum methods. Six informal documents (GRBP-83-32-Rev.1, GRBP-83-48-Rev.1, GRBP-83-49, GRBP-83-50-Rev.1, GRBP-83-53, and GRBP-83-55) addressing equivalence methodology, drum specifications, and code of practice frequency were submitted for potential adoption at the extraordinary GRBP 83 Part II session.

JATMA submitted this position on the draft UN Regulation for tyre abrasion at GRBP-83-54. JATMA requests adoption of the indoor drum test method under conditions equivalent to the vehicle test method for type approval. JATMA proposes that the Generic transfer function coefficient should be 1.14, calculated excluding tyre code 127 which exhibits significant variation. JATMA also proposes that the abrasion index range for tyres used in the Annex 4 procedure should be set between 0.4 and 0.5, and that no restrictions should be imposed on baseline test facilities when applying the Specific Transfer Function.

Proposal to amend GRBP-83-32-Rev.1 to ensure robust tyre abrasion measurements regardless of test method used. Amendments modify paragraph 6.1 to require test facilities demonstrate equivalence per Annex 4 procedure; insert paragraphs 12.8 and 12.9 deeming inter-facility campaign participants equivalent for C₁ tyres and allowing pre-regulation test data through 1 July 2028; insert Annex 3 paragraph 1.4 requiring inter-facility equivalence assessment; amend Annex 3 paragraph 2.8 with abrasion calculation equations including transfer function coefficient; insert test report items 1.1–1.4 in Appendices 2 and 6; and insert new Annex 4 establishing equivalence demonstration procedure for vehicle and indoor drum test facilities.

Proposal to amend document GRBP-83-32-Rev.1 to renumber Paragraph 6.1. as 6.1.1., renumber current Paragraph 6.1.1. as 6.1.2., introduce new paragraph 1.4. to Annex 3 Introduction, amend paragraph 2.8. with detailed abrasion index and level calculation equations, renumber items in Appendix 2, delete item 1.3. from Appendix 2, and amend item 1.3. in Appendix 6 to clarify transfer function applicability between circuit and drum test facilities.

ETRTO comments on EC/JRC compromise proposal for Annex 4 tyre abrasion. ETRTO proposes an ALI range minimum of 0.5 as feasible and consistent with statistical distribution in MA results, rejecting the 0.7 range as unrealistic. For Generic Transfer Function gain, ETRTO recommends retaining a = 1.38 rather than the revised a = 1.45, to minimize rejection of good vehicle test results. ETRTO requests TFTA ToR amendment to confirm these conditions by February 2027 based on TA-45-9.

Proposal to amend document GRBP-83-32-Rev.1. Paragraph 1.2.9. amended to exclude special use Professional off-road tyres from scope. Paragraph 2.51. amended to read that the authority which has granted type approval may verify conformity control methods, with normal minimum frequency of verifications at least once every three years. Justification states special use tyres should be excluded as no limits will be established for them, and the three-year frequency aligns with Schedule 1 of the 1958 Agreement.