A method for operating a spinning machine with plural spinning stations (1), each case having a take-off roller device (6, 10, 14) for drawing a yarn (9) from a spinning device (2) and a sensor mechanism (26) for checking piecings. When starting a piecing, the theoretical conveying length of the yarn is determined based on the surface speed of the rollers (10, 14), until the piecing reaches the sensor mechanism (26). The deviation of the theoretical conveying length from a desired yarn length, corresponding to the spacing between the spinning device (2) and the sensor mechanism (26), is detected. The deviation is compared with a preadjustable limit value of the permissible deviation. If the limit value is passed, this indicates intolerable wear of the pressure roller (14) and produces a signal.