Side supports for straddle-type seat

1. A vehicle comprising:

a frame;

an engine supported on the frame;

at least one propulsion device operatively connected to the engine to propel the vehicle;

a straddle-type seat disposed on the frame, the straddle-type seat having at least one seating portion;

a steering device disposed generally forwardly of the seat; and

left and right side supports disposed generally laterally of the at least one seating portion on opposite sides of a longitudinal centerline of the vehicle, the left and right side supports having respective left and right support surfaces facing generally laterally inwardly,

the left and right support surfaces moving generally in a direction of a current lateral acceleration of the vehicle from a first position to a second position when the current lateral acceleration of the vehicle is greater than a first predetermined lateral acceleration, and

the left and right support surfaces moving from the second position toward the first position when the current lateral acceleration of the vehicle is less than a second predetermined lateral acceleration.

2. The vehicle of claim 1 , wherein the second predetermined lateral acceleration is approximately equal in magnitude to the first predetermined lateral acceleration.

3. The vehicle of claim 1 , wherein the current lateral acceleration of the vehicle is determined based at least in part on at least one of:

a current orientation of the steering device;

a signal received from at least one lateral acceleration sensor mounted on the vehicle; and

a current degree of compression of first and second suspension elements disposed on opposite sides of a longitudinal centerline of the vehicle.

4. The vehicle of claim 1 , wherein:

the at least one seating portion comprises a driver seating portion and at least one passenger seating portion disposed rearwardly of the driver seating portion; and

the left and right side supports are disposed laterally of the at least one passenger seating portion.

5. The vehicle of claim 4 , wherein a lateral separation between the left and right support surfaces is greater than a width of the passenger seating portion.

6. The vehicle of claim 4 , further comprising a back rest disposed generally rearwardly of the at least one passenger seating portion, wherein the left and right side supports are connected to the vehicle via the back rest.

7. The vehicle of claim 6 , further comprising at least one actuator operative to selectively move the left and right support surfaces between the first and second positions.

8. The vehicle of claim 7 , wherein the at least one actuator is disposed at least in part in the back rest.

9. The vehicle of claim 7 , wherein the actuator selectively moves the backrest between first and second backrest positions to move the left and right support surfaces between the first and second positions.

10. The vehicle of claim 7 , further comprising:

at least one sensor disposed on the vehicle; and

a control unit electrically connected to the at least one sensor,

wherein the control unit causes the at least one actuator to move the left and right support surfaces between the first and second positions at least in part in response to a signal received from the at least one sensor indicative of a current lateral acceleration of the vehicle.

11. The vehicle of claim 10 , further comprising a passenger seat sensor operative to detect the presence or absence of a passenger on the passenger seating portion;

wherein the control unit causes the at least one actuator to move the left and right support surfaces between the first and second positions only when a signal is received from the at least one sensor indicative of a passenger being present on the passenger seating portion.

12. The vehicle of claim 6 , further comprising left and right driver side supports disposed laterally outwardly of the at driver seating portion.

13. The vehicle of claim 12 , further comprising a driver back rest disposed generally rearwardly of the driver seating portion and generally forwardly of the passenger seating portion, wherein the left and right driver side supports are connected to the vehicle via the driver back rest.

14. A method of supporting a rider on a vehicle, the vehicle having:

a frame;

an engine supported on the frame;

at least one propulsion device operatively connected to the engine to propel the vehicle;

a straddle-type seat disposed on the frame, the straddle-type seat having at least one seating portion;

a steering device disposed generally forwardly of the seat; and

left and right side supports disposed generally laterally of the at least one seating portion on opposite sides of a longitudinal centerline of the vehicle, the left and right side supports having respective left and right support surfaces facing generally laterally inwardly;

the method comprising:

receiving a signal indicative of a current lateral acceleration of the vehicle;

comparing a current lateral acceleration of the vehicle to a predetermined threshold lateral acceleration;

moving the left and right support surfaces generally in a direction of the current lateral acceleration of the vehicle from a first position to a second position in response to the current lateral acceleration of the vehicle being greater than a first predetermined lateral acceleration; and

moving the left and right support surfaces from the second position toward the first position in response to the current lateral acceleration of the vehicle being less than a second predetermined lateral acceleration.

15. The method of claim 14 , wherein the second predetermined lateral acceleration is approximately equal in magnitude to the first predetermined lateral acceleration.

16. The method of claim 14 , wherein:

the at least one seating position comprises a driver seating position and a passenger seating position; and

the left and right side supports are disposed laterally of the passenger seating portion,

the method further comprising:

receiving a signal indicative of a passenger being seated on the passenger seating position.

17. A vehicle comprising:

a frame;

an engine supported on the frame;

at least one propulsion device operatively connected to the engine to propel the vehicle;

a straddle-type seat disposed on the frame, the straddle-type seat having at least one seating portion;

a steering device disposed generally forwardly of the seat; and

left and right side supports disposed generally laterally of the at least one seating portion on opposite sides of a longitudinal centerline of the vehicle, the left and right side supports having respective left and right support surfaces facing generally laterally inwardly,

the left support surface moving generally in a direction of a longitudinal centerline of the vehicle when a force is exerted on the left support surface generally in a direction generally opposite a current lateral acceleration of the vehicle; and

the right support surface moving generally in a direction of a longitudinal centerline of the vehicle when a force is exerted on the right support surface generally in a direction generally opposite the current lateral acceleration of the vehicle.

18. A vehicle comprising:

a frame;

an engine supported on the frame;

at least one propulsion device operatively connected to the engine to propel the vehicle;

a straddle-type seat disposed on the frame, the straddle-type seat having at least one seating portion;

a steering device disposed generally forwardly of the seat; and

left and right side supports disposed laterally outwardly of the at least one seating portion, the left and right side supports having respective left and right support surfaces facing generally laterally inwardly,

the left and right support surfaces moving generally in a first lateral direction from a first position toward a second position when the steering device is rotated in the first lateral direction, and

the left and right support surfaces moving from the second position toward the first position when the steering device is rotated in a second lateral direction opposite the first lateral direction.

19. The vehicle of claim 18 , further comprising a mechanical linkage operatively connecting the steering device to the left and right side supports, wherein a rotation of the steering device in the first lateral direction actuates the left and right support surfaces via the mechanical linkage to move the left and right support surfaces in the first lateral direction.

20. The vehicle of claim 19 , wherein the mechanical linkage includes at least one cable.

21. The vehicle of claim 20 , wherein the at least one cable is at least one push-pull cable.

22. The vehicle of claim 18 , wherein:

the steering device is connected to the left and right support surfaces via at least one hydraulic actuator;

a rotation of the steering device in the first lateral direction actuates the left and right support surfaces via the hydraulic actuator to move the left and right support surfaces in the first lateral direction; and

a rotation of the steering device in the second lateral direction actuates the left and right support surfaces via the hydraulic actuator to move the left and right support surfaces toward the first position.

23. A method of supporting a rider on a vehicle, the vehicle having:

a frame;

an engine supported on the frame;

at least one propulsion device operatively connected to the engine to propel the vehicle;

a straddle-type seat disposed on the frame, the straddle-type seat having at least one seating portion;

a steering device disposed generally forwardly of the seat; and

left and right side supports disposed generally laterally of the at least one seating portion on opposite sides of a longitudinal centerline of the vehicle, the left and right side supports having respective left and right support surfaces facing generally laterally inwardly;

the method comprising:

receiving a signal indicative of a current degree of rotation of the steering device in a first direction;

comparing a current degree of rotation of the steering device to a predetermined degree of rotation of the steering device;

moving the left and right support surfaces generally in the first direction in response to the current degree of rotation of the steering device being greater than a first predetermined degree of rotation of the steering device; and

moving the left and right support surfaces from the second position toward the first position in response to the current degree of rotation of the steering device being less than a second predetermined degree of rotation of the steering device.

24. A method of supporting a rider on a vehicle, the vehicle having:

a frame;

an engine supported on the frame;

at least one propulsion device operatively connected to the engine to propel the vehicle;

a straddle-type seat disposed on the frame, the straddle-type seat having at least one seating portion;

a steering device disposed generally forwardly of the seat; and

left and right side supports disposed generally laterally of the at least one seating portion on opposite sides of a longitudinal centerline of the vehicle, the left and right side supports having respective left and right support surfaces facing generally laterally inwardly;

the method comprising:

moving the left and right support surfaces laterally outwardly in response to a current speed of the vehicle to the right being less than a predetermined speed; and

moving the left and right support surfaces laterally inwardly in response to a current speed of the vehicle being greater than the predetermined speed.

25. The method of claim 24 , wherein the predetermined speed is zero.