This paper considers the problem of engine-to-slip dynamics modeling in a sport motorbike. Instead of using the classical approach of multibody modeling, this work takes the challenge of directly estimating the input/output slip dynamics by black-box identification, using data collected with experiments specifically designed for this purpose. The proposed identification protocol allows to derive dynamic models suited for the design of traction control systems for two-wheeled vehicles. After the description of the experimental setup, the fundamental issue of signal processing and data analysis are discussed in detail. The effects of two different control variables are studied: throttle position and spark advance. Although it is common belief that throttle action is not fast enough for slip control, the experimental data analysis – performed in the frequency and time domain – shows that slip control through throttle is only marginally slower than spark advance. This analysis opens the way to the design of advanced traction control systems for two-wheeled vehicles.