does the kx100 have a race class does go in the 85 class

big wheel or little wheel?

State where you are going to be racing (America or whatever country and district) as things do differ from country to country. That way someone from your area will be able to help you with the correct information

it depends where u r. sometimes they want it in the super-mini class and sometimes not. call your local racing division and find out

Generally 85 modified (up to 105cc l think) or school boy. They had a 100 class many years ago.