My wife has a softtail duece with a backrest, if that would fit on hers as well, we are legion riders and do alot of parades

 

If you have a new bike (under warranty) you might look Google at all of the articles (including this forum) about warranties being voided by MoCo for flying large flags. Something about the clutch??? I don't think there's anything about parade speed, but if you want to set a landspeed-endurance record with a 3 X 5 or larger, you might do a little research.

 

Im just looking for something to fly flags In a parade, I'm not looking to run the highway with it