I slightly disagree with reddishp in that Harley has used S&S a lot over the years for R&D. They have sort of a love/hate relationship. HD uses them for R&D, then S&S builds a twin cam motor (not balanced like the B from HD) and HD sues them... S&S then makes 'some assembly required' on the twin cam so you buy heavily patented parts from HD...then HD sues over the Twin Cam name and on and on. S&S is ahead at the moment in engineering with the new X Wedge...a totally new design of v twin with three belt driven cams and 56.5 degree V (HD is 45)... EPA compliant through the new regs coming out in 2010... Check 'em out...