S&S Cycle 640 Camshaft

• For large displacement motors with compression ratios of 10.5-11.5:1

• Can be used in smaller motors with 11:1-12:1 compression ratio

• The S&S 640 cam features the latest design in controlled ramps and is intended for hydraulic lifters

• With lower TDC lifts and faster ramps than the S&S 631 cam, the 640 cam builds higher cylinder pressure

• Therefore it does not require as much compression as the 631