A straddled vehicle comprising: an engine; a drive wheel; a transmission that has a shift cam and is configured to transmit a torque generated by the engine to the drive wheel; a shift pedal operable by a rider for a change of a gear ratio of the transmission; a driver that is configured to operate when the shift pedal is lifted up or pushed down by the rider; a rotation driving member (250, 260) that is configured to rotate the shift cam in conjunction with an operation of the driver; a load detector that is provided at the driver and is configured to detect a load applied to the driver when the shift pedal is lifted up or pushed down; an angle detector that is configured to detect a rotation angle of the shift cam; a load determiner that is configured to determine whether a load condition is satisfied, the load condition being that the load detected by the load detector is larger than a load threshold value (Lb, Ld); an angle determiner that is configured to determine whether an angular condition is satisfied, the angular condition being that the rotation angle detected by the angle detector is larger than a predetermined angular threshold value; a shift determiner that is configured to determine that a shift operation for a change of a gear ratio of the transmission has been performed when the load condition and the angular condition are satisfied, and is configured to determine that the shift operation has not been performed when at least one of the load condition and the angular condition is not satisfied; and a controller that is configured to adjust an output of the engine to change the gear ratio of the transmission when the shift determiner determines that the shift operation has been performed, characterized in that the load determiner is configured to determine a direction of operation of the shift pedal based on the load detected by the load detector, the angle determiner is configured to determine a direction of rotation of the shift cam based on a change of the angle detected by the angle detector, and the controller is configured to not carry out the output adjustment of the engine to change the gear ratio of the transmission when the shift determiner determines that the determined direction of operation of the shift pedal and the determined direction of rotation of the shift cam do not correspond to each other. an engine; a drive wheel; a transmission that has a shift cam and is configured to transmit a torque generated by the engine to the drive wheel; a shift pedal operable by a rider for a change of a gear ratio of the transmission; a driver that is configured to operate when the shift pedal is lifted up or pushed down by the rider; a rotation driving member (250, 260) that is configured to rotate the shift cam in conjunction with an operation of the driver; a load detector that is provided at the driver and is configured to detect a load applied to the driver when the shift pedal is lifted up or pushed down; an angle detector that is configured to detect a rotation angle of the shift cam; a load determiner that is configured to determine whether a load condition is satisfied, the load condition being that the load detected by the load detector is larger than a load threshold value (Lb, Ld); an angle determiner that is configured to determine whether an angular condition is satisfied, the angular condition being that the rotation angle detected by the angle detector is larger than a predetermined angular threshold value; a shift determiner that is configured to determine that a shift operation for a change of a gear ratio of the transmission has been performed when the load condition and the angular condition are satisfied, and is configured to determine that the shift operation has not been performed when at least one of the load condition and the angular condition is not satisfied; and a controller that is configured to adjust an output of the engine to change the gear ratio of the transmission when the shift determiner determines that the shift operation has been performed, characterized in that the load determiner is configured to determine a direction of operation of the shift pedal based on the load detected by the load detector, the angle determiner is configured to determine a direction of rotation of the shift cam based on a change of the angle detected by the angle detector, and the controller is configured to not carry out the output adjustment of the engine to change the gear ratio of the transmission when the shift determiner determines that the determined direction of operation of the shift pedal and the determined direction of rotation of the shift cam do not correspond to each other.