Travel control device

A travel control device for controlling traveling of a straddle-type vehicle, comprising:

• a controller;
• a vehicle speed sensor configured to detect a traveling speed of the straddle-type vehicle;
• and
• an acceleration sensor and a gyro or angular velocity sensor configured to detect a detection target vibration which is a vibration in a yaw direction or roll direction of the straddle-type vehicle and has a frequency within a reference frequency range, wherein
• the controller is configured to:
• perform a deceleration control to decelerate the traveling speed of the straddle-type vehicle if the traveling speed of the straddle-type vehicle detected by the vehicle speed detector exceeds a control start reference speed and if an amplitude of the detection target vibration detected by the vibration detector exceeds a control start reference amplitude a number of times in a plural number of timings, and the number of times that the amplitude of the detection target vibration detected by the vibration detector consecutively exceeds the control start reference amplitude reaches a control start reference number of times;
• and
• stop the deceleration control if the traveling speed of the straddle-type vehicle detected by the vehicle speed detector becomes equal to or less than a target limited speed after the deceleration control is started.