| 摘要 |
PURPOSE:To introduce secondary air smoothly and securely via reed valves by combining two exhaust pipes connected to two cylinders with an ignition timing of an equal interval into one set and providing a single reed valve on each set. CONSTITUTION:Two secondary-air introducing pipes 10 extended from two exhaust pipes 6 connected to No.1 and No.2 cylinders 5 are linked up with each other and conducted to a reed valve 9 on one side, while on No.3 and No.4 cylinders 5, two secondary-air introducing pipes 10 are almost similarly linked with each other to be led to a reed valve 9 on another side. In the pressure wave acting to each single reed valve 9 from each pair of exhaust pipes 6, a negative pressure on one side cannot be denied by a positive pressure on another side, and secondary air can be smoothly introduced via reed valves 9. |
