Zhao Huasen isn't a magician and he definitely didn't invent any magical invisible paint. The artist uses clever photo manipulation tricks to "erase" the bicycles from this set of photos, making people seem like they're riding on air.
Strangely enough, Huasen's set reminds us of Natsumi Yayashi's levitation photos, if only for the way the people in the photos are unnaturally floating.
Maybe someday, someone will invent invisible paint. Until that day comes, Photoshop is the next closest thing.