Just made this today as a 3 hour pet project:
Material is very thin .508mm/.020in acrylic for durability and weight savings, attached with a few strips of packing tape but mostly velcro on the inside for valve stem access/easy removal. Dished to perfection, and then painted to make the coolest kids on the block pee their pants. Oh, and a notch for a lock/cable. Surprisingly the acrylic does not deflect or bend at top speed, even though its so thin, it maintains the proper dish.
I did this mostly for fun so I don't want to hear uppity haters lecturing me on how tacky it is or how it probably won't provide any aerodynamic advantage bla bla bla btw 111th post! whoohoo!
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