A rotational atherectomy system may include a drive shaft, a motor, and a clutch with a threshold torque where the clutch may include a motor plate rotationally connected to the motor, a drive shaft plate rotationally connected to the drive shaft, and a biasing clutch configured to rotationally engage the motor plate and the drive shaft plate, wherein torques less than the threshold torque are transmitted completely between the motor plate and the drive shaft plate, which remain rotationally coupled by static friction, and wherein torques greater than the threshold torque cause the motor plate and the drive shaft plate to rotate relative to one another and cause a residual torque to be transmitted between the motor and the drive shaft, the residual torque being less than the threshold torque and being determined by a kinetic coefficient of friction.
