Engine support structure in motorcycle

A first main frame segment (62) extends rearwardly from a head pipe (4), a second main frame segment (64) pivotally supports a swingarm (12), and an engine casing EC is disposed between the head pipe (4) and the swingarm (12). The engine casing EC includes a crankcase section (28), a cylinder part (30), a cylinder head part (32) and a transmission casing section (34). The first main frame segment (64) includes a first mount portion (56), which is connected with a front portion of the cylinder part (30), and a second mount portion (58) which is connected with a rear portion of the cylinder head part (32). The second main frame segment (64) includes a third mount portion (60) which is connected with a rear portion of the transmission casing section (34).