S&S CYCLE 100" CARBURETED BILLET ENGINE
FOR 1986-2003 SPORTSTER HARLEY-DAVIDSON
MOTORCYCLES - NATURAL FINISH (31-9891)




S&S SB100 engines come assembled with a natural aluminum finish. Crankcases have 1986-1990 four-speed style cam geometry and 1991-2003 five-speed style drive side. Primary and transmission components not included. S&S motor 31-9891 is for 1986-2003 Harley-Davidson Sportster models.

Features and benefits include:
  • Square motor configuration (equal bore and stroke) produces excellent torque, greatly increases engine life, and reduces mechanical engine noise
  • S&S Super G carburetor with teardrop air cleaner
  • S&S high flow Super Stock cylinder heads
  • S&S 600 camshaft
  • S&S forged pistons, 10.3:1 compression ratio
  • Adjustable pushrods and pushrod cover assemblies
  • Hydraulic tappets and S&S forged roller rocker arms
  • S&S billet gear cover kit and billet aluminum rocker covers
  • Includes oil pump and oil filter mount
  • One year warranty




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