The present invention refers to a motor saw arrangement comprising a support plate attached to the motor saw chassis or motor saw motor, a detachable clamping plate and a detachable guide bar arranged between the support plate and the clamping plate. The sup- port plate is provided with two first recesses and at least one threaded hole, while the clamping plate is provided with two protrusions adapted to fit inside the respective two first recesses when the clamping plates is attached to the support plate and the protrusions each have a height that exceeds a corresponding height of the guide bar. The guide bar is pro- vided with two keyhole-shaped slots and with a longitudinal slit between the two keyhole- shaped slots and the support plate is further provided with an alignment means. The invention further relates to a method to remove and/or replace a saw chain from a guide bar and to a guide bar intended and adapted for the motor saw arrangement described herein.