Once you get half way through "Screech's Sprint" you will transform into the bird, and, normally, you will fly up to Screech and the race will start. If you come up right behind Screech to where the race will not start yet, and you fly upwards (you must have both characters at this point for this to work), you will then hit the the ceiling and hurt yourself causeing yourself to blink. Quickly, while you are still blinking, pass Screech and head off to the rest of the level without having to worry about doing it in good time.