The centrifugal-weight-type V-belt automatic transmission is widely used for the light engines of scooters and agricultural machines, etc. for being compact, efficient and comparatively cheap. The operating section of this centrifugal weight, which contains the metal weight coated with thermoplastic resins in its movable pulley, is lubricated with grease to provide stability and life (reliability) for its operation. However, the grease filling work not only requires a substantial number of man-hours but also various seal parts to prevent, during running, the grease from being splashed about by the centrifugal force and dust particles from intruding. To overcome these restrictions, research has been conducted on how to free the centrifugal weight from the grease by experimenting with various self-lubricant resin compositions as the coating materials for this metal weight. And, as a result, the durability, the acceleration response, the productivity and the maintenance of the automatic transmission have been improved.