To provide an exhaust pipe collective structure having a higher degree of freedom in layout.
An exhaust passage 4 communicating a plurality of exhaust ports 2 provided in an engine 1 with outside air consists of a first exhaust pipe 8 and a second exhaust pipe 10 communicated with the exhaust ports 2, a first expansion chamber communicated with the first exhaust pipe 8, a second expansion chamber 14 communicated with the second exhaust pipe 10, a combination chamber 16 having an exhaust pipe 30 communicated with the outside air, a first additional pipe 18 for communicating the first expansion chamber 12 with the combination chamber 16, and a second additional chamber 20 for communicating the second expansion chamber 14 with the combination chamber 16. The first exhaust pipe 8 is arranged eccentrically to the left side of a vehicle body 6 in the cross direction of a vehicle beyond the center position thereof in the cross direction of the vehicle, and the second exhaust pipe 10 is arranged eccentrically to the left side of the vehicle body 6 in the cross direction of the vehicle beyond the center position thereof in the cross direction of the vehicle. The first exhaust pipe 8 and the second exhaust pipe 10 as well as the first additional pipe 18 and the second additional pipe 20 have the same pipe length and opening area with each other.
KAKU YOICHI
Yoshiaki Naito
Cui Shu Tetsu
Toru Miyasaka
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