S&amp,S Cycle 570 Gear Drive Easy Start Cams Complete Kit 106-5243 Manufacturer Part No. 106-5243 Convert your Twin Cam to a gear drive Kit includes cams, all gears, gaskets, bearings, bolts and bearing plate Designed for 88in. to 106in. engines with compression ratios between 9:1 and 10:1 Intake Opening (degrees): 20