Episode I Racer Glitches

Glitching through a wall
There are two main sections in which you can glitch through a wall and fall to your death:

1. Choose any racer, and head onto Executioner. Play normally until you get to the area leading up to the first anti-gravity tube (not the tunnel after the sharp bend to the right, the bit afterwards). Hold down left or right, then press A or D respectively, until your pod is hugging the wall. Then, while still holding left or right, and A or D respectively, boost. If done correctly you'll glitch through the wall, land out of bounds, and fall to your doom. You'll be righted in the anti-gravity tube.

2. Choose Mars Guo, then head onto Abyss. Stay on the top level of the first tunnel until you hit the final straight that eventually leads out of the tunnel, then boost straight forward without tapping either left or right. Due to the wall's small size, you'll glitch over the wall, and once again, fall to your death.