there is no real way of finding out what year it is after 1998. in 1997 richard long was killed and he was the brains of GT. after that the marking guy changed the manufacture of their bikes. after that they stopped stamping the year in the frame. the first couple of years of dyno cruisers serial number started off as yrc96 or 7 with meant year code 1996 or 1997. after that they would start off with a W and there is no way to pin point the year. now one last thing to help date a post 1998 dyno is the front of the frame. yours is for sure a mid 2000 and up dyno. before the year 2000 the front of the frame (headtube) had a D painted on it. after mid 2000 for the 2001 model year, dyno started putting aluminum head badges on their frames. so from 2000 to 2004 dyno had the head badge. in 2005 they became Kustom Kruiser. the 2005 KK said Santa Ana on the head badge. in 2006 KK started saying Taiwan. so if you got a head badge it's 2000 to 2004. if it has a D painted then it is pre 2000.