two potential issues.
first, see if it is truly dye bleeding or simply black streaks (dirt). dye bleeding comes off easy with a cleaner. Black streaks requires oxalic acid cleaners
if it is dye bleeding, a bathroom cleaner with bleach will work (wear old clothes and not your new favorite Harley tee). still recommended to wax
If it is black streaks, a good hull cleaner with oxalic acid (you can mix your own), followed by waxing.
The only time I have truly witnessed dye bleeding is when I attempted to re-dye sunbrella fabric on my 28 year old top and didnt wash the top a second time :facepalm: