Abstract: The field of micro- and nano-mechanics has seen rapid advances driven by applications in sensing, microscopy, and precision instrumentation. Accurate, time-resolved characterization of mechanical dynamics is essential for understanding device behaviour and improving performance. However, conventional optical and electrical methods face trade-offs between sensitivity, linearity, and bandwidth, while frequency-domain approaches are limited in capturing transient dynamics. Here, we present a frequency comb-based time-domain tracking technique for directly observing the full-range dynamic motion of atomic force microscopy (AFM) micro-cantilevers. By leveraging electro-optic sampling between femtosecond optical pulses and ultra-precise photocurrent timing signals, our system enables real-time measurements across six orders of magnitude – from ~ 30 pm thermal fluctuations to ~ 20 µm nonlinear oscillations. The technique reveals complex behaviours including mode coupling, hysteresis, bifurcation, and transient modulation, while maintaining calibration fidelity through thermomechanical noise. This approach bridges the longstanding gap between ultra-sensitive and wide-range motion tracking, offering a powerful tool for studying nonlinear dynamics in micro- and nano-scale mechanical systems. Looking ahead, the method lays the groundwork for advances in high-resolution force sensing, AFM probe optimization, and the broader exploration of dynamic behaviour in precision microsystems.