INTERNAL COMBUSTION ENGINE

To provide an exhaust port capable of enhancing a purification rate of unburned HC in the exhaust port.SOLUTION: An internal combustion engine comprising an exhaust port 12 communicating with a combustion chamber, comprises a deflecting part 51 formed on an inner surface of the exhaust port. The exhaust port comprises an inside communication part 12a that communicates with the inside of the combustion chamber in a radial direction and extends in an exhaust downstream direction, and an outside communication part 12b that communicates with the outside of the combustion chamber in the radial direction and extends in the exhaust downstream direction. The deflecting part is configured to redirect flow of exhaust gas so that the exhaust gas flowing along the outside communication part is directed to the inside communication part, or so that the exhaust gas flowing along the inside communication part is directed to the outside communication portion.SELECTED DRAWING: Figure 2 【課題】排気ポート内での未燃ＨＣの浄化率を高めることができる排気ポートを提供する。【解決手段】燃焼室に連通する排気ポート１２を備える内燃機関は、排気ポートの内面上に形成された偏向部５１を備える。排気ポートは、燃焼室の径方向内側に連通すると共に排気下流方向に延びる内側連通部分１２ａと、燃焼室の径方向外側に連通すると共に排気下流方向に延びる外側連通部分１２ｂとを備える。偏向部は、外側連通部分に沿って流れていた排気ガスが内側連通部分に向かうように、又は内側連通部分に沿って流れていた排気ガスが外側連通部分に向かうように、排気ガスの流れの向きを変えるように構成される。【選択図】図２