S&S has a complete line of motorcycle performance products ranging from motorcycle slip-on exhaust, bolt on performance intakes, motorcycle big bore kits, or a complete motorcycle engine.Whether you fancy a Evolution (1984 to 1998, Harley), Sportster (smaller Harley V-Twin), Flathead, Knuckelhead, Panhead or Shovelhead, S&S performance engines and parts can meet the needs of American V-Twin motorcycle builds.S&S Cycle has been in the engine business for over 50 years. What started as a passion for speed by founder George Smith Sr., S&S continues to manufacture a full line of go-fast V-twin engines and parts in the world. Founded in Blue Island, IL. in 1958, they moved to Viola, WI. in 1969. In 2004 an additional facility was opened in LaCrosse, WI.