Enable the "Artillery", "Lunar" and "RC Kart" cheats, then enter Velo's challenge. At the beginning of the race, press L and you should get three rockets or bombs. Shoot Velo, and if you are in the lead throw bombs behind you, in case he is behind you and catching up. When he is at the jump over the road that you have both already been on, sometimes he will make a mistake and must go around the corner and jump again. Note: You might be able to lap Velo if you are lucky enough. He must then pass you two times in order to get in the lead.