Morgantown, W. Va.- MX Sports announces today the National Classes, Supplemental Rules and all-new Limited Class Clarification chart for the 2013 Red Bull AMA Amateur National Motocross Championships at Loretta Lynn's.

Classes that were previously categorized as Stock or Modified will now be referred to as Limited and Non-Limited divisions, according to machine modifications that are eligible in each class.

The all-new Limited Class Clarification chart is designed to clarify which items on the machine should remain stock and which items can be modified. To view the 2013

Limited Class Chart, click HERE.

To view the 2013 National Classes, click HERE.

To view the 2013 Supplemental Rules, click HERE.

The 2013 Red Bull AMA Amateur National Motocross Championship will take place Sunday, July 28 - Saturday, August 3 at Loretta Lynn Ranch in Hurricane Mills, Tenn. For more information, visit the series website at www.mxsports.com.