S&S Cycle Crankcase Breather Reed Valve

Item # : 280037

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  • Manufacturer: S and S Cycle


S&S Cycle Crankcase Breather Reed Valve

  • Consists of 3 steel reeds that are normally in the closed position
  • When pistons travel downward in the cylinders, the air in the crankcase is compressed and pressure in the crankcase below the pistons increases
  • Pressure causes the reeds to open, allowing the air and oil mist in the crankcase to escape into the cam chest
  • When pistons change direction and begin traveling back upward in the cylinders, a vacuum is created in the close, preventing air from entering the crankcase
  • A slight vacuum is maintained in the crankcase and oil scavenging is greatly improved
  • Recommended on large displacement engines 100in. or larger