scrub em
I have a 23 and cleaned my sails at the end of last season w/ off the shelf sial cleaner purchased @ West Marine. It did a great job. I cleaned both sides. Used bleach/water solution for stains. They whitened up beautifully. I then protected them w/ off the shelf sail waterproof stuff. A little backbreaking but well worth it when you hoist those white sails.Good luck