I eat a normal primal diet during training. If I am doing a long training ride or event, I like to use larabars as in ride fuel. It takes time to transition, so be paitent with your riding. I changed my eating during the off season, so I did not feel it on the bike so much.
It will be a challenge to eat clean during CX season as there is always tons of beer around.
I saw you mentioned that you were training for a 100 mile MTB race. I also do endurance and XC MTB racing, as well as cyclocross. I'm interested to hear about what you eat for training. This is the end of the first week and I'm really struggling on the bike.