My poor motor used to travel unprotected on the Enterprise’s rear rack (see picture above right) but now she stays covered. There are better covers, especially custom versions that cover everything including the bottom then zip up to keep dust out. But for something quick and dirty, a grill cover works well. Beware, though, grill covers are far from equal. After wearing a couple out, I can tell you the cheap ones aren’t worth it. And the expensive ones from home depot are still dramatically cheaper than custom covers.
The cover depicted at left is a Charmglow 58″ wide, 44″ tall and 24″ deep model made of pretty stout fabric. It has no grommets, though, so you’ll have to add those yourself to secure it on the paramotor. I bought an inexpensive grommet kit where you pound your own holes then pound in the grommets. All you need is a hammer and block of scrap wood, the kit contains everything else. Add four grommets then use a bungee at the bottom to the cover in place. Connecting the bungee to two grommets and around the bottom holds the cover’s bottom fast so it won’t ride up the paramotor cage.
With these covers being open underneath, dusty roads will leave your machine covered in powdery dust depending on where you’re driving. But they keep UV off the harnesses and avoid rain issues.