Choro Q Racing Cheats (Nintendo 64)

In Track 4, go through the waterfall and stop at the series of tight turns. There is a
road on the left that doubles back. Follow it to find a plateau with a sword in a stone.

Approximately a quarter of the way around the track is a waterfall, off which you can
jump. This 
  waterfall has a rock on top of it. Line yourself up just to the right of the rock, and
aim slightly towards the right. You will jump just to the right of the opposite waterfall
into a storm drain.

About half way around the course there is a barrier guiding your car to the left. Ignore
it and drive through the wall into an underground passage.

There is an old train track at the beginning of the race. Race along this fast enough and
jump from section to section, and cut off part of the track.