Abstract: A jet propulsion watercraft includes a vessel body, an engine, a jet propulsion unit, a weight information obtaining processor, an engine controller, and a target rotational speed determining processor. The engine is accommodated in the vessel body. The jet propulsion unit is driven by the engine and propels the vessel body. The weight information obtaining processor obtains weight information regarding a weight of the vessel body. The engine controller controls an engine rotational speed such that a vessel velocity reaches a predetermined set velocity. The target rotational speed determining processor determines a target engine rotational speed corresponding to the set velocity in accordance with the weight information. The engine controller controls the engine rotational speed such that the vessel velocity reaches the set velocity based on the target engine rotational speed determined in accordance with the weight information.

Abstract: A jet propulsion watercraft includes a vessel body, an engine, a jet propulsion unit, a weight information obtaining processor, an engine controller, and a target rotational speed determining processor. The engine is accommodated in the vessel body. The jet propulsion unit is driven by the engine and propels the vessel body. The weight information obtaining processor obtains weight information regarding a weight of the vessel body. The engine controller controls an engine rotational speed such that a vessel velocity reaches a predetermined set velocity. The target rotational speed determining processor determines a target engine rotational speed corresponding to the set velocity in accordance with the weight information. The engine controller controls the engine rotational speed such that the vessel velocity reaches the set velocity based on the target engine rotational speed determined in accordance with the weight information.

Abstract: A marine vessel includes a hull, a propulsion device arranged to propel the hull by a driving force of an engine that has a throttle valve arranged to be electrically controlled so as to open and close, an operation lever arranged to be operated by a marine vessel operator to adjust a throttle opening degree of the throttle valve and arranged to hold an operation position, a fine adjustment switch arranged to be operated by the marine vessel operator to increase or decrease the throttle opening degree to finely adjust the throttle opening degree that has been adjusted by the operation lever, and a control unit arranged to adjust the throttle opening degree based on an operation amount of the operation lever and an operation state of the fine adjustment switch.

Abstract: A marine vessel includes a hull, a propulsion device arranged to propel the hull by a driving force of an engine that has a throttle valve arranged to be electrically controlled so as to open and close, an operation lever arranged to be operated by a marine vessel operator to adjust a throttle opening degree of the throttle valve and arranged to hold an operation position, a fine adjustment switch arranged to be operated by the marine vessel operator to increase or decrease the throttle opening degree to finely adjust the throttle opening degree that has been adjusted by the operation lever, and a control unit arranged to adjust the throttle opening degree based on an operation amount of the operation lever and an operation state of the fine adjustment switch.