Looking for ideas for DIY mud flaps for fenders. I got what I thought were "SKS Longboard" fenders in the 65mm size for my e-bike running 2.15" Big Apple tires, but they're not nearly as long as the narrower Longboard offerings, and the mudflap is that little short rubber piece that angles out instead of extending down 6" or so. There's still about 8" of clearance from the tip of the rubber piece down to the floor, much higher than other Longboard fenders.

I thought about taking a couple of pieces of a larger size old inner tube and laminating them together with vulcanizing cement, then cutting out a long-ish shape and attaching it somehow to my fenders. I want them to extend farther down, both front and rear - rear mainly to try to keep junk off my utility trailer. It rained on me coming back from the grocery store last weekend and the front of my trailer got super nasty from junk off the rear tire.