Abstract: A valve device is configured to adjust an opening degree of a flow path for fluid, and includes an axial member, a valve body, and a biasing member. The axial member is configured to be fixed to the flow path. The valve body is rotatable about the axial member, and is configured to be rotated in a closing direction in which the opening degree is reduced, and to be rotated, by the use of a fluid flowing down through the flow path, in an opening direction in which the opening degree is increased. The biasing member is provided to the axial member inside the flow path, and is configured to bias the valve body to rotate in the closing direction.

Abstract: A valve device is configured to adjust an opening degree of a flow path for fluid, and includes an axial member, a valve body, and a biasing member. The axial member is configured to be fixed to the flow path. The valve body is rotatable about the axial member, and is configured to be rotated in a closing direction in which the opening degree is reduced, and to be rotated, by the use of a fluid flowing down through the flow path, in an opening direction in which the opening degree is increased. The biasing member is provided to the axial member inside the flow path, and is configured to bias the valve body to rotate in the closing direction.

Abstract: An exhaust pipe includes a tubular portion and a space forming portion. The tubular portion forms an exhaust flow path in an exhaust system of an internal combustion engine. The tubular portion has a tubular shape. The space forming portion is provided along at least one of an inner surface and an outer surface of the tubular portion and forms at least one branch space between the space forming portion and the tubular portion. The at least one branch space communicates with the exhaust flow path and has a function as a side-branch muffler. The at least one branch space includes a space with a length that is one third or more of an entire length of the exhaust system.

Abstract: A riding type vehicle has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, the riding type vehicle including two first sensors arranged on both left and right sides more to a front side than a rear end of the vehicle, the two first sensors configured to detect an obstacle target located on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning.

Abstract: A riding type vehicle has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, the riding type vehicle including two first sensors arranged on both left and right sides more to a front side than a rear end of the vehicle, the two first sensors configured to detect an obstacle target located on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning.

Abstract: A riding type vehicle has a driving source, a left wheel and a right wheel, a transmission configured to receive power from the driving source to independently operate and drive the left wheel and the right wheel with regard to a rotation direction and a rotation speed, and caster wheels separately provided in a front-rear direction with respect to the left wheel and the right wheel, the riding type vehicle including two first sensors arranged on both left and right sides more to a front side than a rear end of the vehicle, the two first sensors configured to detect an obstacle target located on a rear side, the obstacle target being a target becoming an obstacle at the time of reversing or turning.