The movie was late 80s early 90s I can remember it was about the earth was at war and the one scene I can remember was these giant ramps and these ships using the ramps to get to space. Now their was these soldiers riding what looked like futuristic motorcycles and this tank that was trying to climb one of the ramps to get away from the motorcycles

"Big Wars" was the movie. I remember it well because the motorcycles had a single wheel and mounted a large auto-cannon on one side of the bike if I recall correctly. They were fighting for control of the Martian colonies.