Major goal of the new design is to offer full-valuable bike with great ability to be folded, stored in small spaces (cases, car trunks etc..). Main feature of the design is the circular frame. It allows unusual folding. Both wheels have overhung mounting. After releasing safety lock nuts wheels can be turned around relevant axis into the frame. Because of folding of the rear wheel momentum transfer from crankset to rear wheel must be divisible. Common chain system is replaced by belt system with outer toothing. Belt is mounted on two rollers. Both “chainwheel” and pinion have outer toothing as well. It altogether ensures right direction of turning and divisibility of the whole system.