Pulley assembly with an improved clutch for a continuously variable transmission

A vehicle comprising an internal combustion engine and a continuously variable transmission having a pulley assembly, said assembly comprising a shaft having an axis, a supporting clement rotatable about said axis, a first half pulley rotationally connected to said supporting element, a second half pulley facing said first half pulley for defining a seat adapted to accommodate a belt of said transmission, at least one of said first and second half pulleys being longitudinally mobile with respect to said supporting element, and a clutch comprising a second supporting element connected to said shaft, a drum connected to said supporting element and accommodating said second supporting element, and a plurality of friction elements hinged to said supporting element about respective hinge axes to selectively cooperate with said drum, said pulley assembly being characterised in that respective centres of gravity of said friction elements are located before the respective hinge axes with respect to a given direction of rotation of said shaft which defines a forward running condition of said vehicle such that each friction element is configured to rotate about the respective hinge axis to contact said drum with a rotating direction that is the same as said given direction of rotation.