Abstract: A rotary internal combustion engine having a single toroidal cylinder and a set of orbital pistons attached to a rotating head or toroidal cylinder cover. The toroidal cylinder is divided into two chambers by two rotating disk valves perpendicular to the toroidal cylinder. Each rotating disk valve has a piston slot or opening that allows the orbital pistons to pass through the rotating disk valves while maintaining sealed chambers within the toroidal cylinder. The rotating disk valve that seals the compression chamber has a void within it that forms a pre-combustion chamber, which receives the compressed fuel-air mixture and releases it on the opposite side of the disk valve into the combustion chamber. The two orbital pistons and rotating disk valves allow the four cycles of the toroidal internal combustion engine to occur simultaneously within the toroidal cylinder.