Trace Moisture Measurement in Racing Car Tyres Application Note Attention to detail is paramount in the demanding arena of motor sports. Among the many factors influencing performance, the trace moisture content in high-performance racing car tyres is a critical yet frequently underestimated consideration. This application note examines the importance of accurately measuring and maintaining low moisture levels in tyres, outlines the detrimental effects of elevated moisture content and discusses the techniques employed to monitor and control moisture levels effectively. The Impact of Moisture on Tyre Performance Moisture content in racing car tyres plays a significant role in overall performance. Trace amounts of moisture can influence how a tyre behaves, impacting grip, handling and the car’s ability to perform consistently. Controlling moisture content is therefore essential for many reasons. Fluctuations of Tyre Pressure: Moisture inside tyres can vaporise when exposed to the high temperatures generated during a race. This vaporisation leads to fluctuations in tyre pressure, which can compromise the stability needed for consistent performance and precise handling. Maintaining stable tyre pressure is critical for drivers to achieve ideal results on the track. Sensor Performance: While the monitoring sensors located in each wheel are typically well-sealed and protected, environmental factors such as moisture can still interfere with the operation of the IR temperature sensors potentially causing issues. Image courtesy of Wayne Taylor Racing Image courtesy of Wayne Taylor Racing Application Requirements To accurately measure trace moisture in racing car tyres, teams must meet several application requirements: Use of Sensitive Moisture Meters: Using high-precision hygrometers capable of detecting low moisture levels inside the tyre to ensure reliable readings. Controlled Sampling Procedures: Bleeding a small, representative air sample from the tyre without depressurising it or contaminating the sample, maintaining the tyre’s integrity and gas composition. Consistent Measurement Protocols: Standardising the sequence and method of measurements (e.g., always sampling from the same tyre position and at similar conditions) to ensure repeatability and comparability across sessions. Calibration and Maintenance: Regularly calibrating measurement devices before each session to maintain accuracy and perform routine checks to prevent sensor drift or malfunction. Environmental Controls: Storing tyres in dry, well-ventilated areas before use minimises ambient moisture absorption and avoids exposing tyres to humid conditions as ambient moisture can enter the tyre cavity during mounting. Data Recording: Systematically logging all moisture readings along with relevant environmental and tyre data for analysis and performance tuning

Key Factors Dewpoint Measurement A fundamental method for evaluating moisture levels. By determining the dewpoint, operators can accurately assess the amount of water vapour present and ensure that the air meets the required standards for specific applications. Reliable dewpoint monitoring is essential for maintaining system efficiency and preventing issues caused by excess moisture. Sensor Technology Advanced sensor technologies are critical for precise moisture measurement. Instruments featuring aluminium oxide sensors provide high accuracy and reliability, making them ideal for monitoring...