| 摘要 |
PURPOSE:To improve cooling effect through running blowing by installing a pair of ignition plugs which are arranged around a fuel injection valve to a front part of a cylinder head, and arranging the ignition plugs spirally substantially around the fuel injection valve. CONSTITUTION:In a two-cycle single-cylinder engine 16 for a motorbike, a triangular cavity which composes a combustion chamber is formed on a lower face side of a cylinder head 30, and on its top part a high-pressure fuel injection valve 46 is installed. A pair of bilateral screw holes 55, 55 each having an ignition plug 56 screwed therewith are formed around the high-pressure fuel injection valve 46 on the cylinder head 30. The ignition plugs 56 are arranged on a front part of the cylinder head 30 and symmetrically in respect to a center line in a widthwise direction of a vehicle body. The high-pressure fuel injection valve 46 and the ignition plugs 56 are not superposed on each other in a plan view, and a running blowing 59 is in direct contact with the high-pressure fuel injection valve 46 and the ignition plugs 56 to effectively cool them. |
