Abstract: An exhaust device for a 2-cycle engine including an exhaust pipe having an expanded portion, and a curved outlet pipe inserted in the exhaust pipe in such a manner that its one end opening is disposed in a position in the expanded portion in which the output power loss of the expanded portion can be decreased and its the other end opening is disposed at one side of the exhaust pipe. The use of a curved pipe as an outlet pipe enables the outlet pipe to be positioned such that its one end opening is disposed in a suitable position in the expanded portion while its the other end opening is disposed at one side of the exhaust pipe, thereby allowing the outlet pipe to have a suitable length and the volume of the resonance chamber in the exhaust pipe to be increased.

Abstract: A cooling liquid temperature control system for an internal combustion engine cooled by a cooling liquid which in turn is cooled by a heat exchanger, wherein a primary bypass opened and closed by a low operating temperature thermostat valve and a secondary bypass opened and closed by a control valve are branched from a cooling liquid outlet passage connected between an engine jacket and the heat exchanger. The control valve can be opened depending on the degree of the opening of the throttle valve. The secondary bypass is branched from the cooling liquid outlet passage. The two passages are respectively opened and closed by a high operating temperature thermostat valve. The secondary bypass is communicated with the primary bypass and the other passage communicated with the heat exchanger.