When doing bike sprints, there's a couple things you can do to maximize output:

1. Put the bike seat up as high as you can without feeling like you're reaching too much or overextending your legs.

2. Try to keep your torso from swaying side to side too much. Focus on just moving the legs and arms.

3. As your legs get tired, also think about pulling and pushing with the arms. Keep the arms closer to your sides and let them do some work alongside the legs!

4. Look at the RPMs or Watts and pick a number to stay above the whole time.