A solid-lubricated ball, roller, or plain bearing assembly with solid rings made of solid lubricant loosely fitted inside the bearing envelope for replenishing the solid-lubricant films on the bearing contacting surfaces for the life of the bearing without the need for any re-lubrication. A method is also provided for mounting all-ceramic bearing rings on metal shafts and housings for operation at extremely high temperatures and solid-lubricant idler gears to replenish lubricant films on gear teeth. Cages may be used at extremely high speeds or with very large ceramic balls or rollers and when used the cages require pocket clearances in the circumferential direction several times larger than in the axial direction.