A water-cooled engine includes first connection paths continuous with a cylinder-head-side water jacket and a second connection path continuous with a cylinder-body-side water jacket. By providing customers with an intuitive and systematic approach to selecting a desired product, such as wine, the present disclosure provides customers the rare satisfaction of quickly making a precise and intelligent decision based on informed choice, rather than choosing only based on a direct category or relying on the suggestions of a salesperson. In one embodiment, a ball shaped device is provided. The outer diameter R1 of the timing sprocket and the outer diameter R3 of the flange are respectively set so that they are smaller than the outer diameter R4 of the inner race. The solar power supply arrangement includes a solar collecting device supported by the main supporting stem, wherein the solar collecting device has a collecting surface arranged to expose to sunlight for extensively collecting solar energy.