S&S .640 Inch lift cams are used in S&S T124 engines, this cam is designed to make horsepower. Intended for engines of 95 CID or more with compression ratios between 10.5:1 and 11.5:1. 3,000 - 6,000 rpm. Includes 640G gear drive camshaft set and inner gears, outer cam drive gear kit, and camshaft installation kit for 1999-2006 Harley-Davidson® big twin models (except 2006 Dyna®).