| 摘要 |
PURPOSE:To improve the cooling performance of the titled device by deviating jackets to a substantially half part of a side away from inlet and outlet ports to communicate with each other, in the device in which inlet and outlet ports of water jackets on the cylinder side and the head side are opened on the outer surface of the same side. CONSTITUTION:In the V-type internal combustion engine for motorcycle, a water jacket 21 is provided in a cylinder block 3, and a cooling water outlet port 16 communicating therewith is formed, A water jacket 23 is provided in the cylinder head 4 and a cooling water outlet part 17 communicating therewith is formed. In this case, the water jacket 23 on the head side is branched in a plurality of branch water passages 23a-23f within the cylinder head 4 toward the lower surface thereof. These branch water passages open on a substantially concentric circle at the lower surface of the cylinder head 4 on the substantially half part side away from the inlet port 16 and outlet port 17 for cooling water. By this arrangement, flowing-out of cooling water from the inlet port 16 to the outlet port 17 in a short-circuiting manner can be prevented, hence the cooling performance can be improved. |
