Multi-Level Validation Methodology for Self-Healing Bicycle Tires

While bicycle technologies have evolved into highly engineered systems, their tires remain vulnerable, prone to damage, and contribute to end-of-life waste. This study proposes a strategy to extend tire lifespan through self-healing technology. Existing damage-mitigation solutions, such as reinforced tires, sealants, and inserts, are limited by trade-offs including restricted effectiveness, increased rolling resistance, and compromised user experience. To overcome these, a thin, integrated self-healing polymer layer is introduced within tubeless bicycle tires as a practical intermediate solution. A comprehensive, multi-level validation methodology spans material (TRL 3), patch (TRL 4), tire (TRL 5), and initiation of field testing (toward TRL 6). While broadly applicable to various self-healing materials, a Diels–Alder-based reversible polymer network is selected for its mechanical robustness and rapid autonomous healing at room temperature. Material-level tests demonstrate substantial recovery within 3 min and near-complete recovery within 20 min. Patch- and tire-level experiments confirm effective sealing of punctures up to 3 mm, while maintaining rideability for larger damages up to 5 mm, even under repeated loading and low temperatures (−20 °C). Dynamic and field tests further evaluate performance under realistic conditions, with benchmarking against conventional sealant. Overall, the results highlight the potential of self-healing layers to enhance puncture sealing, improve sustainability, and reduce maintenance.