Saddle-riding vehicle provided with a frame having reduced stiffness against yaw movements

A saddle-riding vehicle comprising:

• an engine assembly and a frame to which is connected said engine assembly, wherein said frame comprises:
• a steering tube to which a steering assembly that controls a front wheel is pivotally connected;
• a central part to which is hinged a first end of a fork which also comprises a second end pivotally connected to a rear wheel;
• and
• a front part extending between said steering tube and said central portion, wherein said front part comprises a first frame side and a second frame side separated in the direction of a width of the vehicle, wherein said frame sides are made of a first metallic material having a first modulus of elasticity;
• and
• a first plate connecting said engine assembly to said first frame side and a second plate connecting said engine assembly to said second frame side, said plates being made of a second metallic material having a second modulus of elasticity lower than said first modulus of elasticity of said first metallic material,
• wherein said front part of said frame comprises first portions extending from said steering tube to corresponding second portions,
• wherein said second portions extend between said corresponding first portions and said central part of said frame,
• wherein said second portions have a mono-component configuration and wherein said first portions have a lattice configuration,
• wherein each of said first and second plates connects a component of said first portion of a corresponding frame side to a portion of a cylinder head and/or of an engine block of said engine assembly.