A vehicle and a height adjustment system for the vehicle are disclosed. A valve includes a member movable between a first position operating first and second piston mechanisms to raise an end of the vehicle to a first height, a second position operating the first and second piston mechanisms to lower the end of the vehicle to a second height and a third position maintaining the end of the vehicle at one of the first height and the second height. A first fluid line extends between the first piston mechanism and the valve to fluidly connect the first piston mechanism and the valve. Additionally, a second fluid line extends between the second piston mechanism and the valve to fluidly connect the second piston mechanism and the valve. The first fluid line and the second fluid line are fluidly connected to the valve independently of each other.

A vehicle and a height adjustment system for the vehicle are disclosed. A valve includes a member movable between a first position operating first and second piston mechanisms to raise an end of the vehicle to a first height, a second position operating the first and second piston mechanisms to lower the end of the vehicle to a second height and a third position maintaining the end of the vehicle at one of the first height and the second height. A first fluid line extends between the first piston mechanism and the valve to fluidly connect the first piston mechanism and the valve. Additionally, a second fluid line extends between the second piston mechanism and the valve to fluidly connect the second piston mechanism and the valve. The first fluid line and the second fluid line are fluidly connected to the valve independently of each other.

A suspension system including hydraulic circuits that extend between dampers located at opposite corners of the vehicle and at least one load distribution unit that is connected in fluid communication with at least two hydraulic circuits. The load distribution unit includes a manifold block with a cylinder bore, a pair of pressure tubes, a piston rod assembly, and an integral rod guide and pressure tube coupler. The pressure tubes are partially received in the cylinder bore to define a pair of opposed cylinders and mate with the integral rod guide and pressure tube coupler. The piston rod assembly includes a piston rod and a pair of opposed pistons that are slidingly received within the opposed cylinders. In addition to retaining the pressure tubes, the integral rod guide and pressure tube coupler supports and permits the piston rod to slide longitudinally relative to the manifold block.

The present invention relates to an improved control system of the trim of motorcycles with more than two wheels. More in particular, it relates to motorcycles which have at least three wheels and can lean sideways by virtue of the presence of a so-called wheel tilting system. The present invention improves the HTS hydro-pneumatic system developed by the same Applicant, which is the object of Patent EP 2 046 589, so as to improve the vehicle trim, above all while cornering with the leaned vehicle.

A method is provided for determining whether or not ground contact loss is imminent for wheel of a vehicle, the vehicle including a vehicle body having a vertical extension in a vertical direction, the wheel being allowed to be subjected to a relative vertical displacement, in the vertical direction, in relation to the vehicle body, the vehicle further being such that a maximum value of a vertical displacement of the wheel relative to the vehicle body is limited to a relative vertical displacement limit; the method including determining an actual relative vertical displacement of the wheel relative to the vehicle body, determining a limit margin as the difference between the actual relative vertical displacement and the relative vertical position limit, and determining that ground contact loss is imminent for a wheel if the limit margin is within a predetermined vertical threshold range.

A suspension system including four dampers each having a compression chamber and a rebound chamber. First and second hydraulic circuits interconnect the compression and rebound chambers of the front dampers, while third and fourth hydraulic circuits interconnect the compression and rebound chambers of the back dampers. A first longitudinal hydraulic line extends between and connects the first and third hydraulic circuits and a second longitudinal hydraulic line extends between and connects the second and fourth hydraulic circuits. A single bi-directional pump is connected in-line with a fluid distribution line that extends between and connects the first and second longitudinal hydraulic lines a can pump fluid in opposite directions through the fluid distribution line to provide active roll stiffness.

An air management system for a vehicle having a first pneumatic circuit and a second pneumatic circuit, in which the first and second pneumatic circuits are pneumatically connected in a neutral position via a cross-flow mechanism. The first pneumatic circuit is configured to independently adjust air pressure of a first side of the vehicle. The second pneumatic circuit is configured to independently adjust air pressure of a second side of the vehicle. The system is configured to establish pneumatic communication between the first and second pneumatic circuits when the air management system is not independently adjusting the adjust air pressure of the first side of the vehicle and the air pressure of the second side of the vehicle in the cross-flow mode.

An air management system for a vehicle having a first pneumatic circuit and a second pneumatic circuit, in which the first and second pneumatic circuits are pneumatically connected in a neutral position via a cross-flow mechanism. The first pneumatic circuit is configured to independently adjust air pressure of a first side of the vehicle. The second pneumatic circuit is configured to independently adjust air pressure of a second side of the vehicle. The system is configured to establish pneumatic communication between the first and second pneumatic circuits when the air management system is not independently adjusting the adjust air pressure of the first side of the vehicle and the air pressure of the second side of the vehicle in the cross-flow mode.

A suspension system including four dampers is disclosed where each damper includes a compression chamber and a rebound chamber. First and second hydraulic circuits interconnect the compression and rebound chambers of the front left and back right dampers, while third and fourth hydraulic circuits interconnect the compression and rebound chambers of the front right and back left dampers. A first bi-directional pump is connected between the first and second hydraulic circuits and a second bi-directional pump is connected between the third and fourth hydraulic circuits. The first and second bi-directional pumps can either pump in the same direction or in opposite directions. The level of pitch and roll stiffness can be adjusted by running the first and second bi-directional pumps to change the pressure in select hydraulic circuits of the system.

A suspension system including four dampers each having a compression chamber and a rebound chamber. First and second hydraulic circuits interconnect the compression and rebound chambers of the front dampers, while third and fourth hydraulic circuits interconnect the compression and rebound chambers of the back dampers. A first longitudinal hydraulic line extends between and connects the first and third hydraulic circuits and a second longitudinal hydraulic line extends between and connects the second and fourth hydraulic circuits. A single bi-directional pump is connected in-line with a fluid distribution line that extends between and connects the first and second longitudinal hydraulic lines a can pump fluid in opposite directions through the fluid distribution line to provide active roll stiffness.