Record of Webex participants attending the TA-52-11 meeting over two days, listing participants’ names, affiliations, and join and leave times for each session.

Progress report on the Task Force on Tyre Abrasion covering February to October 2026. Work on UN Regulation on tyre abrasion for C1 tyres has concluded, with new UN R186 adopted at WP.29’s 199th session in June 2026, implementing a two-stage approach with initial application from 30 June 2028 and increased stringency from 30 June 2033. C2 test method development is ongoing with formal working document postponed to February 2027; C3 tyre work commenced with brainstorming session in October 2026 targeting working document in February 2027. The Task Force proposes conversion to an Informal Working Group.

Presentation of ZF’s tread wear tester for C3 tires, available for operation in Passau until at least September 2029. ZF intends to operate the test rig in cooperation with fka for method development, validation, and correlation with on-road testing. The machine will be fully operational at ZF with climate chamber, cooling and filtering, and powder supply, with target operational date Q1 2027. FKA plans to acquire the machine and operate it at the ZF site for the first few years.

Test findings from seven circuits in the Republic of Korea show that estimated SRTT17S abrasion levels at 20 °C exceeded the specified range of 25–75 mg/(kmt) at six of the seven circuits tested. These results indicate that conducting UN R186 tyre abrasion tests in the Republic of Korea on circuits that meet the current range would be challenging at present. The Republic of Korea suggests reviewing the suitability of the current circuit abrasion level range and commits to support efforts to establish a circuit abrasion level range applicable to circuits worldwide.

Presentation of a concept for accelerated tire wear testing using a standard truck with independent steering on left and right sides. The method employs steering actuators from existing steered rear axles to create longitudinal and lateral slip, accelerating tire wear while maintaining representative behavior. Reference tire and test specimen can be mounted on separate axles to compare wear rates.

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.

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.

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.

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.

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.

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.

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 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.