S&S Cycle Compression Release Hole Plug - Each [MPN: 90-4916]

  • S&S Cycle Compression Release Hole Plug - Each 90-4916_1733552
Brand: S&S Cycle MPN: 90-4916
$37.21
$37.21 $24.95
Est Arrival: June 6–10
Ships same day
In stock

Compression Release Hole Plug

  • Designed to be used in S&S cylinder heads for Twin Cam, 4 bore Evolution Big Twin, and Super Sidewinder Plus style S&S engines
  • Consists of a small valve that opens during starting and allows a portion of the cylinder pressure to escape into the exhaust port of the cylinder head
  • Reduced cylinder pressure makes it easier for the starter to turn the engine
  • When the engine starts, the valve closes and the engine runs normally, with full compression
  • Electric Compression Releases:
  • Electric compression releases are solenoid operated
  • They automatically open when the starter button is depressed and automatically close when the starter button is released
  • When installed on SSW+ or Twin Cam style S&S engines, S&S electric compression releases require the use of S&S die-cast Twin Cam style rocker covers or similar covers with a central hole or chimney
  • The chimneys in the rocker covers are required to provide clearance for the solenoids that operate the compression releases
  • Electric compression releases are compatible with S&S rocker boxes for Evolution engines
  • Manual Compression Releases:
  • Manual compression releases are activated by a cable similar to a choke control
  • Before starting, the handle is pulled, which opens the compression releases; when the engine fires, the increased cylinder pressure automatically closes the compression releases
  • Can be used with any style rocker cover
  • Made in USA
ColorAluminum / Silver
Dimensions3 in x 2 in x 2 in
MPN90-4916
MPN Alt 2009-9082, ssc90-4916, 493278
Product NamePlug
TypeCompression Release / Hole Plug, 14mm
UnitsEach
Weight0 lb 5 oz
S&S Cycle Compression Release Hole Plug - Each [MPN: 90-4916]

$37.21

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