<p>During rising temperature, cage gradually becomes unstable due to the real-time thermal and centrifugal expansions of bearing parts. To analyze the instability mechanism, a novel dynamic model of ball bearings including thermal and centrifugal effects is established, which in real time can modify the structural sizes of bearing parts in the dynamic model and the thermal characteristics in the thermal network model to attain the more actual dynamic behaviors compared to the ordinary models. On this basis, the effect of thermal expansion of bearing parts on contact angle, pocket clearance and guiding clearance is analyzed and the dynamic behaviors of bearing parts in temperature rise are investigated; next, only the change in pocket clearance and guiding clearance is conducted to analyze the dynamic behaviors; subsequently, initial contact angle is varied to analyze the dynamic behaviors. By comparing these dynamic behaviors under different conditions, it finds that thermal expansion prompts the reduction in the contact angle to cause the instability of cage and enhancement of contact loads. Moreover, at the high temperature, the collision of the ball with pocket arouses the irregular trajectory to wear pocket, while the circular trajectory due to the rotation of cage along the guiding surface induces the strong impact to wear cage. Compared to existing methods, this innovative approach attains the coupling of heat and dynamics to effectively predict the dynamic behaviors of bearing parts in high speeds and high temperature, which can effectively guide the relevant experiments to reduce the experimental period.</p>