Nervous Twitch
Doh! You had a near perfect run on a Hard or Extreme track, but blew it after the last checkpoint.
The easiest track to do this on is definitely "Home Run". It is the first hard track unlocked. Make sure to use the Phoenix 250cc bike for this achievement as well.
Just continue through the track and learn it enough that you can get to the ring of fire without any faults. Once you do get to the ring of fire and have no faults, press the "B" button to reset your rider, and the achievement is yours.
Please view the video as well: