After incidents in Ridorana Cataract you can chase with Rikken and his friends.
To do that go to a front of Reddas's residence and talk twice with Rikken. Agree with his proposition.
There are 100 races for you (of course you don't have to participate in all at once ;)) For each won race you get a prize and advance to the next race. If you loose, you repeat the same race.
To run straight you have to press X and O by turn. By pressing only a few times X you sidetrack to the left and by pressing O to the right. There is no sense to press button as fast as you can because Vaan won't run faster. First of all you have to press them rhythmically so Vaan didn't stop at every step. You have to cut corners too. At the beginning it has no matter but later your opponents are much faster and cutting corners is necessary. After start run straight for a while and a little turn to the left (press X twice and continue running straight) [screen 1]. When you will be close to this bend turn a little to the right and next straight run at a slant. Just before bend to the right (start to press O quickly). Due to that you will pass it with inner line as close as it is only possible [screen 2]. Wait a while and when Vaan will be orientated straight to the finish line instead of pressing O start to pressing X quickly. Race is finished when you reach the stairs [screen 4].
Despite all appearances Raz is the fastest one. However it is not visible at the beginning. His biggest problem is to keep the balance - In first races he collapses and stays behind. In later races your victories will depend whether you "help" him in collapsing or not. Task is pretty easy. When you go out of first bend (which turns into left) you should rapidly turn to the right to cross Raz's way and cause his collapse [screen 3]. Now, your only task is to calmly get to finish.
10 gil, Echo Herbs
100 gil, 2x Balance Mote
300 gil, 2x Float Mote
800 gil, 3x Teleport Stone
1500 gil, 2x Vanishga Mote
2500 gil, 2x Reflectga Mote
3500 gil, 2x Hi-Ether
4500 gil, 2x Holy Mote
6000 gil, 2x Hastega Mote, Caramel (276g)
8000 gil, 2x Scathe Mote, Slime Oil (1717g)
10000 gil, 2x Elixir, Unpurified Ether (1783g)
As you have probably noticed awards are only listed till 10th race and then listed every 10 races. It doesn't mean that in races between you get nothing. There is just a simple schema: 1st race - 1x Potion, 11th - 2x Potion, 21st - 3x Potion etc. All together you get 55 things for races between the main ones. Remember, max. amount of things you can carry on is 99 so it is worth to make a place for them
After winning 100th race you are announced by Rikken the fastest man in whole Ivalice. If you want to race more it is not problem. Nevertheless, You will gain no more awards in races and the level will not raise anymore.