To access the Hard Mode, highlight your kart and Press Y + A and your highlighted kart will shrink to Tiny Mode, continue and Highlights the cup of your choice and you will ride very tiny until the current cup ends! WARNING: this will be very difficult! even when your Tiny until the current cup ends, you will ride the same speed as a Normal Kart. to reverse this effect, just Press Y + A again in the Kart Choose Menu. Have fun!