A straddled vehicle comprising: an engine; a drive wheel; a transmission configured to transmit a torque generated by the engine to the drive wheel; an operation member configured to be operated by a rider in order to switch a gear ratio of the transmission; a load sensor configured to detect a load applied to the operation member by the rider; a measurer configured to measure a time length from a time point at which the load detected by the load sensor exceeds a first threshold value (TD1,TU1); a shift determiner configured to determine that an operation of the operation member by the rider is a shift operation for switching the gear ratio of the transmission; and a controller configured to adjust an output of the engine in order to switch the gear ratio of the transmission when the shift determiner determines that the operation of the operation member by the rider is the shift operation, characterized in that the measurer is configured to measure the time length from a time point at which the load detected by the load sensor exceeds a first threshold value (TD1,TU1) until a time point at which the load detected by the load sensor exceeds a second threshold value (TD2,TU2) larger than the first threshold value (TD1,TU1) as an operation time length; the shift determiner is configured to determine that an operation of the operation member by the rider is a shift operation for switching the gear ratio of the transmission when the operation time length measured by the measurer is equal to or shorter than a first time length, and configured to determine that the operation of the operation member by the rider is not the shift operation when the operation time length measured by the measurer is longer than the first time length. an engine; a drive wheel; a transmission configured to transmit a torque generated by the engine to the drive wheel; an operation member configured to be operated by a rider in order to switch a gear ratio of the transmission; a load sensor configured to detect a load applied to the operation member by the rider; a measurer configured to measure a time length from a time point at which the load detected by the load sensor exceeds a first threshold value (TD1,TU1); a shift determiner configured to determine that an operation of the operation member by the rider is a shift operation for switching the gear ratio of the transmission; and a controller configured to adjust an output of the engine in order to switch the gear ratio of the transmission when the shift determiner determines that the operation of the operation member by the rider is the shift operation, characterized in that the measurer is configured to measure the time length from a time point at which the load detected by the load sensor exceeds a first threshold value (TD1,TU1) until a time point at which the load detected by the load sensor exceeds a second threshold value (TD2,TU2) larger than the first threshold value (TD1,TU1) as an operation time length; the shift determiner is configured to determine that an operation of the operation member by the rider is a shift operation for switching the gear ratio of the transmission when the operation time length measured by the measurer is equal to or shorter than a first time length, and configured to determine that the operation of the operation member by the rider is not the shift operation when the operation time length measured by the measurer is longer than the first time length.