1. An image forming apparatus comprising: a rotary image bearing member; a charging device to charge the image bearing member; an irradiator to irradiate the image bearing member to form a latent electrostatic image thereon; a developing device to develop the latent electrostatic image formed on the image bearing member by irradiation with a developing agent comprising toner to obtain a visible image; a transfer device to transfer the visible image from the image bearing member to a recording medium; a first cleaner that slidably contacts the image bearing member to remove toner remaining thereon; a driving mechanism operably connected to the image bearing member to drive the image bearing member at different linear speeds; a noise detector provided in the vicinity of the image bearing member to detect noise; and an abnormal noise predictor device to predict outbreak of abnormal noise during image formation based on noise detected by the noise detector when the image bearing member is driven not during image formation at a linear speed different from that during image formation.