Go to West Valley Freestyle in one player mode. Go down to the basement and go off one of the jumps. It will take you to a place on top. Follow the way then do the big jump at the end to complete the "Brave The Vertical Drop" challenge. The "Trophy awarded" message will appear and you unlock the Custom Zebra motorcycle.
Get the "Cross Training" trophy. To do this easily, participate in an exhibition race under the hard difficulty setting. Set the laps to "3" and opponents to "0". It is best to use a Super Cross Track because you will need a lot of jumps. Run the race and do tricks until you hit 5,000 points. You will automatically get first place because you are the only one on the track.
