| 摘要 |
PURPOSE:To prevent dispersion of air containing unburnt fuel produced at starting operation into the outer air by providing a communication path between the combustion chamber and the crank chamber while arranging a decompression open/close section in the way of said path. CONSTITUTION:A decompression path 17 opening to the combustion chamber 9 of 2-cycle engine is formed while penetrating the cylinder head 8 and a valve seat 18 is formed at the open section at the combustion chamber 9 side of said path 17. A valve head 20 of decompression valve 19 is provided contactably against said valve seat 18 as the decompression open/close section extending while penetrating through the cylinder head 8. A decompression valve housing 21 is fixed to the outside of cylinder head 8 to communicate the decompression path 17 with the internal decompression chamber 22. The decompression valve 19 is opened/closed by means of a decompression shaft 23 through operation of a decompression lever 24. The decompression chamber 22 is communicated through a tube 27 constituting a portion of communication path to the crank chamber 6. |
