how much horsepower difference is there between yosh stage1 and megacycle385/385 cams on a 1397 motor with a mild clean up on the head?Would any of you sell yosh cams to buy the megacycles?I've got the yosh cams and they seem to work well but I hear a lot of talk about the bigger megacycle cams?I plan to go with a 1390 and wonder should I just leave yosh in the bike.Any help is appreciated?