Press Back or press Jump + D-pad to perform special moves.
Discus Throw extra points
You can get a lot more points if you dive to the left and catch the disc. It is more difficult, but can earn much more points.
Easy BMX points
Note: This trick requires a controller with a turbo feature. Begin a BMX race and intentionally move slowly. Hold B while turbo is enabled to quickly bounce the bike up and down to accumulate points.