Ant Man is continuously shrinking and jumping on the back of a winged ant to catch up to a fast moving car.
Couldn't find info on an ant, but a bee flies at 15 mph/24 kph.
Would be hard to catch up to a car driving at 50-60 mph.
Dude, if you break it down there are so many problems with Ant-Man as a concept. He keeps his normal mass (he can hit like a bullet as per the first movie) but the flying ant can carry him. He can grow but that same mass is now spread over a much larger area which should make him either weaker or intangible. He's supposed to wear the helmet while shrinking or growing, but takes it off in the school. He shrinks and then runs across the room, which means a trip of seconds now takes minutes or hours.
I mean, there are problems with every superhero, but size changers just come with a host of them.