| 摘要 |
PROBLEM TO BE SOLVED: To provide a valve gear suppressing wear by reducing contact pressure on an upper surface of a valve lifter of a cam surface of a first rocking cam.SOLUTION: This valve gear includes two intake valves of different valve stem length per a cylinder, a drive cam having torque transmitted from a crankshaft, a first and a second rocking cam 19, 20 operating the two intake valves respectively, and a transmission mechanism converting rotary motion of the drive cam to rocking motion and transmitting the same to the first and the second rocking cam. In the first rocking cam, curvature radii d1, d2 of a base circle part 19c of a cam surface 19b and an arc shape lift part 19d formed continuously from the base circle part 19c are formed larger than a base circle part 20c and a lift part 20d of a cam surface 20b of the second rocking cam 20 respectively. Consequently, contact pressure to a valve lifter of the cam surface of the first rocking cam is reduced. |
