S&S MR103CE Easy Start chain drive camshaft kit for 1999-2006 HD Big Twins except 2006 HD Dyna are recommended for modifed engines with larger displacement and higher compression. More torque and horsepower than bolt in cams can deliver. Stock valve springs in 2005-2006 engines may be used with MR103 and HP103 cams. An S&S oil pump and cam support plate, along with a stock 2007 and later style hydraulic cam chain tensioner upgrade is highly recommended for chain drive cams.
