Originally Posted by FarCry
Do you have leech adjustment lines on your sails? If so, pull those until the flapping stops assuming everything else is trimmed correctly. Read the top section called "Reducing power by reefing" here Sails tuning recommendations - Sparcraft masts
I'll do some reading. I do have the leech lines on main and jib. I have tried different tension on the lines but cannot get rid of all the flapping. The lines do help some.